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Drainage Reports - 02/02/1994
L - ! '. H% Final 1 1 1 1 1 1 1 1 FINAL DRAINAGE & EROSION CONTROL REPORT FOR PROVINCETOWNE P.U.D. PHASE 1 (SOUTH LEMAY AVENUE) FORT COLLINS, COLORADO PREPARED FOR: MR. KEN DUECK EDGEMONT, INC. 15701 EAST FIRST AVENUE AURORA, COLORADO 80011 SEPTEMBER 1, 1993 (REVISED NOVEMBER 12, 1993) PREPARED BY: PARSONS & ASSOCIATES CONSULTING ENGINEERS 432 LINK LANE PLAZA FORT COLLINS, COLORADO 80524 (303) 221-2400 PROJECT NUMBER 92.21 KEN 1 1 .1 1 1 1 �1 .'1 1 TABLE OF CONTENTS Introduction Site Description Master Drainage Historic Drainage Drainage Criteria Drainage Under Developed Conditions Erosion Control Conclusions and Recommendations References Figure 1 Vicinity Map. Figure 2 Historic Drainage Appendix A Drainage Calculations Appendix B Erosion Control Calculations Appendix C Approved Drainage Reports Exhibit A Back Pocket Drainage & Erosion Control Grading Plan 3 8 8 9 18 19 22 2 4 1 1 1 Introduction 1 .1 L 1 t 1 PRELIMINARY DRAINAGE & EROSION CONTROL REPORT FOR PROVINCETOWNE P.U.D. FORT COLLINS, COLORADO This drainage report has been prepared along with preliminary engineering drawings to provide design information for the development of 93 single-family and 93 multi -family residences along the west side of South Lemay Avenue just south of its intersection with Trilby Road. This report was prepared in conformance with the City of Fort Collins'Storm Drainage Design Criteria and Construction Standards (Reference 1), and with all' -previous drainage reports written for this area and listed as references. Site Description Provincetowne P.U.D. is a 57.92 acre parcel of land located at the southwest corner of South Lemay Avenue and Trilby Road (See Figure 1). More specifically the property is located in the northeast corner of Section 13, Township 6 North, Range 69 West of the 6th Principal Meridian, City of Fort Collins, County of Larimer, State of Colorado (Reference 9): The development will consist of 20 one -acre (low -density) tracts, 73 1/3-acre (medium density) and 93 multi -family (high density) tracts. -1- 6 VICINITY i�AP SCALE: - i"=2000' ' The historic land use of this site has been irrigated farm land with an easterly slope of 5% to 7%. A number of infrastructure improvements have been built as part of the ' Provincetowne/Portner S.I.D. South Lemay Avenue was constructed along the eastern ' boundary of this project and Trilby Road was constructed' along the northern boundary. Water, sewer and drainage improvements were installed as part of the construction of Brittany ' Drive and Province Road. The land on adjacent sides of this project is vacant with sparse vegetation and littered with a considerable amount of garbage. The only portion of this area not proposed for residential development is the 5.0 acre Redeemer Lutheran Church site in the southwest corner of the intersection between Trilby Road and Brittany Drive which is currently tunder construction. Master Drainage 1 Provincetowne P.U.D. is within the Fossil Creek Drainage Basin. The master drainage ' study for this basin is entitled the Fossil Creek Drainage Basin - Master Drainageway Planning Study and was completed by Simons, Li and Associates for the City of Fort Collins in August ' of 1982.(Reference 10) As part of this report, various drainage improvement alternatives twere analyzed, and alternative 3,was ultimately selected and approved by the Storm Drainage Board. This alternative identified structural methods of improving the Fossil Creek, and ' identified a number of "on-line" detention areas which could -substantially reduce or eliminate tthe need for detention on some sites. Please refer to Appendix "C" for appropriate section of the report. All areas developed within Provincetowne P.U.D. will have on -site detention ' attenuation, to reduce flows to 100-year historic release rates. 1 -3- �SovTN .JIoE JEMCE l-£1RER, t-t+V. LID!Q -'•' tw ..h i :i: .�` ��7`.--arJ:i4 �::Q .O .1 �1HIs�, / �'J�,' i /) •!� NN LAK EPN w MER Y 4 .48 Ate. \ 9 NA \ \ \ •nine r-A _ PROVINCETOWNE MD. for `= T ., Dueck Development Inc. Drainage Map •. , r i i �ii • '\� ..r • k C W 34.82 A— I{I{ •••'" aysyy a i.c •r n rr. care •rusu•r+ r.u.r... .r..r.rr„r ��•� o�c�a�ncam :��ipp�ipp3�ipp1p� B00 L•.■ �6iE�IlYIrY��O p IlC0Eiiq Y3��Y�11i10M �camaim.c�aa n=a©ic�aicc T naaodmaoo oomcm©aoo aoomo®cao acaaaaaaa, oacaaaocc oa000mnum aoacm0000 SCALE' 1 •4OC, CONTOUR INTERVAL• 2 FEET. , TOPOGRAPHY ON THIS MAP COMFLES. WRH NATIOMLL MAP ACCURACY STNOARCd TOPOGRAPHY COMPILED BY PHO OG AhNETR1C METHODS FROM 6' FL VERTICAL AERIAL PHOTOGRAPHY EXPOSED ON APRIL 23.1901. LEGENO `—� EXIST. Ploe. i•.zso-�' INDEX CONTOUR ' --1 INTERMEOIATE CONTOUR C� DEPRESSION — — — FENCE `•" '-` '•• GUARD RAIL =_=== DIRT ROAD PAVED ROAD RAILROAD STREAM DITCH ) E CULVERT HEADNALJ, d BUILDING Q TREE OUTLINE A POKER-TELE• POLE Q2 DESIGN POINT BASIN BOUNDARY PROPERTY LINE PARSONS Q ASSOCIATES q2.2!-KEN CONVASING [NON[{Al - 03 ILIA L. Iin. .. C.swr C.% .[. [DS„ ' Existing Drainage Resorts 1 The historic drainage pattern runs from the southwest to the northeast as overland ' flow with cumulative flow falling into Fossil Creek. As part of the construction for Lemay ' Avenue and Trilby Road, drainage crossings and channels were constructed to convey the flow to Fossil Creek. The construction of Province Road and Brittany Drive, as part of the ' Provincetowne/Portner S.I.D., also provided for a series of storm drains and open channels ' to improve the conveyance of runoff from this site. There are a number of drainage reports completed for developments within this area, and the more pertinent ones are discussed ' below. All the drainage reports for this area are provided in the reference list at the end of this report. Appendix ' C".contains relevant sections of all referenced reports. The Provincetowne/Portner S.I.D. drainage report was completed in December of 1984 (Reference 3). This report identified all of the necessary drainage requirements for the Dueck 1 properties. The historic runoff determined from this drainage report was the basis for the ' design of all road crossings in this area. The Provincetowne/Portner S.I.D. report identifies the need for detention on a tract by tract basis with some detention provided by the large ' open channels. As the report states "... this report assumes that on -site detention will be ' provided as tracts are developed throughout the Provincetowne/Portner project, and .the drainage facilities included in this S.I.D. have been sized accordingly." 1 1 -5- ' From 1984 to 1986, Brittany Drive, Trilby Road and South Lemay Avenue were built in a series of construction projects. The first project, designed in April of 1984, was for the ' development of the Somerly at Provincetowne P.U.D. which is located in the 13 acres southwest of the Brittany Drive and Trilby Road intersection (Reference 5). The drainage report and grading plan called for detention ponds and storm sewers to outlet into a 24" RCP ' along the east side of Brittany Drive within the proposed Redeemer Lutheran Church site. Off - site drainage channels along Brittany Drive and Trilby Road would collect the runoff and convey the flow to Fossil Creek. Although the Somerly site was never developed the off -site ' improvements included; Brittany Drive, the storm sewer under Brittany Drive, the water line .,;.:under Brittany Drive, -and the off -site drainage channels., The Final Drainage Report for South Lemay Special Improvement District #86 prepared_... by Engineering Professional, Inc. (Reference 7) in July of 1985 used the drainage information 1 developed in the Provincetowne/Portner S.I.D. report to size the drainage improvements. Three culverts under South Lemay Avenue were sized to convey the 100-year developed runoff although, only the 100-year historic event of 73.5 cfs can be released (Sheet 8 - ' Hydrology Calculations; Provincetowne/Portner S.I.D.). Also constructed during this project ' was a large drainage channel along, the west side of South Lemay Avenue. This channel conveys the runoff from the majority of this area to the intersection of Lemay Avenue and Trilby Road. 1 -6- 1 1 1 1 1 The Final Drainage & Erosion Control Report for Redeemer Lutheran Church was completed in May of 1992 (Reference 4). This site is scheduled to begin construction in April of 1993. The drainage for this site is designed to intercept the runoff from the off -site area to the west (basin D-2, from the Provincetowne report, Reference 3). This flow will be conveyed through a 24" RCP, and outlet at the northwest corner of the property into the existing drainage channel along Trilby Road. The runoff from the church site and 0.6 acres of off -site flow to the southwest will be concentrated into a detention pond at the northwest corner of the property. This pond is designed to release the 100-year historic flow rate of 7.8 cfs into the existing drainage channel on the south side of Trilby Road. Appendix "C" contains -relevant sections of this report. -7- Design Criteria The Rational formula as identified in The City of Fort Collins Storm Drainage Design ' Criteria has been used to calculate runoff from this site. The rational method is widely ' accepted as a method for predicting runoff from basins of less than 200 acres. 'Manning's equation was used to identify the capacity of all channels and street gutters. All ' coefficients, nomographs and design values used in this report were provided for in The Fort ' Collins Storm Drainage Design Criteria. (Reference 1) ' Historic -'Drainage ' Existing drainage reports were reviewed for accuracy and conformity to current design methodology. After discussions with Fort Collins Stormwater Utility, it was decided to re- evaluate the Basins draining into this project. Figure 2 shows the Basins used to evaluate the ' Historic Drainage conditions including existing roadways (Brittany Drive and Province Road). All design points are existing culverts and/or curb inlets that collect and convey historic storm ' flows downstream into the development. 11 1 U 1 ' The 100-year Historic event was evaluated to determine actual Q's and a summary table can be found in Appendix A (Sheet 1 of 29). The Historic Drainage Basins conform to ' the Basins as outlined in the Provincetowne/Portner S.I.D. report. Modifications were made ' to overland and channelized flow times to reflect currently accepted City of Fort Collins methodology. Modifications were made to allow for routing caused by existing streets and ' changes to the Redeemer Luther Church site at the northwest corner of the project. ' There are a number of important flow quantities that have changed due to historic ' runoff re -calculation. Most notably is the 100-year Historic outfall from all upstream basins at Design Point #6. A new 100-year Q of 94.9 cfs has been calculated vs. the 73.5 cfs ' outfall that was reported by previous studies (Portner/Provincetowne S.I.D.) This is due to ' a general decrease in the total time of concentration caused by applied Channelized flow times from Figure 4.4.1.4-1 of the Urban Drainage Manual. All other Q's increase but cause no problems for existing conveyance elements. ' Drainage Under Developed Conditions The development of the 20 one -acre lots will reduce runoff excepted from this area, ' and the 73 1/3-acre lots will contribute a similar amount of runoff as was predicted in the ' Provincetowne drainage report. The multi -family tract will consist of 92 units with detached garages and a corresponding increase to total impervious area. No overlot grading is ' anticipated for the one -acre lots and a minimal amount of grading is expected in the 1/3-acre 1 -9- I: ' lots with only about 3,000 to 6,000 square feet of each lot becoming developed. Considerable grading of the multi -family area is anticipated, this will occur in the northeasterly corner of the development and have no impact on upstream flow quantities. 1 ' Grass -lined swales will convey the majority of the runoff away from this site and eventually into Fossil Creek. Most of the existing storm sewers will be utilized as part of the ' proposed drainage system with some improvements around their inlets and outlets. Minor ' improvements will include implementation of erosion protection, and cleaning out the pipes. Existing channels in Tract "A" channel Number (5), (6) and (7) will be regraded and sloped drops and rip rap protection will be added. The existing stormwater collection system at Rumford and Brittany will be modified to match the proposed road intersection (see sheet 14 ' of 16) Other drainage improvements include curb openings and cross pans, and are shown ton Drainage and Erosion plan, (sheet 15 of 16) in the back pocket of this report. A 3.5 Ac Ft detention pond will be added to the Northeast corner of the project to attenuate downstream flows, a detailed discussion of proposed improvements follows this section. 1 Brittany Drive and Province Road are existing collector streets with adequate flow ' capacity and existing inlets. The streets proposed for this development will be classified as ' residential streets which are 46 foot flowline to flowline sections, and 28 foot flowline to flowline sections on Biscay and Somerly Lane. 11 t -10- ' No off -site improvements are proposed for this site. The irrigation lateral running through the western end of the property is currently not being actively used. The irrigation ' canal will be re-routed, with agreement from current users, as shown on the grading and ' drainage plan. Culverts will be provided to convey irrigation flows below Biscay Lane and Rumford Lane (sheets 22A, Appendix A). 1 ' General ' For the following discussion, refer to the Drainage, Grading and Erosion control plans in the back pocket of this report (sheets 14 and 15). All lots within this P.U.D. are covered tby a Blanket Drainage Easement. Developed flows quantities were calculated and appear in ' 1 Appendix A (sheets 5 & 6) in the Storm Drainage design data tabulations. Points of concentration correspond to the numbers as shown on the Drainage and Erosion Control Plan. 1 Channel section normal depths were calculated for all design channels along with velocity and ' Froude Number calculations, Appendix A (sheets 9 through 16). ' As outlined in the Historic Runoff section, all historic flows were re -calculated and ' appear in Appendix A of this Report. Sheet 14 of 16 shows existing pipes, inlets and pipe grades. Pipe capacity calculations were performed for all pipes, existing or proposed and can be found on sheets 21 and 22 of Appendix A. 11 1 1 -11- r ' Existing roadway improvements have caused a change in the proposed drainage patterns on Brittany Drive. A significant portion of Brittany Drive north of Rumford Lane was ' constructed as individual northbound and southbound lanes separated by a 12' landscaped median. The section of roadway north of Rumford southbound (or the western most road) was elevated by as much as 1.80 above the corresponding flowline of the northbound lanes. ' The new roadway intersections (i.e. Battsford Circle, Benson Lane and Deerhurst Circle) require a considerable amount of work to allow the existing road sections to transition. This adjustment causes stormwater to sheet flow across these intersections and into the flowlines ' of down gradient roadways. The corresponding flow quantities are small (3.5 cfs for minor storm outfall from Basin B) and should have no adverse impact on safety or drivability. ' Downstream conveyance elements are sized to handle these flows and a detailed discussion of these Design Basins follows. The proposed development is located on a easterly facing slope of 5% to 7%. All lots will be covered by a blanket drainage easement. The ' intent of the proposed lot drainage schematic (sheet 15/16) is to allow natural grades to match the proposed street section at the front of each lot. Sheet flows will be routed around ' structures and buildings to the rear and/or side lot lines. Finished floors of buildings and structures will be graded at a minimum of 5% for the first 10' away from the foundation. Sheet flows will then follow the natural topography in order to preserve existing flow patterns ' and minimize unnecessary site grading. 11 1 -12- ' Detention Storage On -site detention will be provided for in the northeast corner of the site. A three and one half acre foot pond is designed to attenuate developed flows from this area. Calculations for detention storage and pond volume can be found in Appendix A (sheets 18 thru 20). On-, site detention is required due to limited downstream easements. These drainage easements ' are to be acquired by the City of Fort Collins after the propoerty has completed legal foreclosure. An outfall channel is designed and will be extended to Fossil Creek. As tcalculated by the revised Historic release rates for this report, only the 100-year historic event ' can be released (94.9 cfs) to the east across Lemay Avenue. This assumes that as upstream basins develop, future development will have to provide for on -site detention and release at ' the 100-year historic'rates. Basins A and C Basins A and C consist of large (one acre) lots bordering Province Road and Brittany Drive. Basin A includes the existing irrigation lateral which will be re -aligned (with irrigation ' users approval) along the back lot lines and through culverts as shown on the drainage plan. Flows within Basin A will follow natural topography and fall towards Biscay Lane and Brittany ' Drive. Stormwater will collect at the corner of Brittany Drive and Province Road and will be ' conveyed to the east via 2-24" RCP culverts and 4' concrete curb inlets already existing at 1 -13- ' the intersection,. as designed in the Province/Portner S.I.D. study. Existing culverts are sized ' to allow the 100-year historic outfall from upstream basins, please reference .culvert calculations on sheet 21 and 22 of Appendix A. ' Basin C flows fall to the east and collect in Somerly Lane or fall to the major channel in Tract A at the easterly boundary of the project. A shallow channel will also provide ' channelization of flows along the back lot lines of Lots 16 through 20. All existing inlets were sized for street flows on Province Road. Brittany Drive, Trilby Road and Lemay Avenue. Relevant sections of approved drainage reports are included addressing inlets in existing ' sections of roadway - see Appendix "C". ' Basin B ' Basin B consists of Basin B and B-1. Basin B-1 stormflows will flow easterly and be ' intercepted by Rumford Lane or fall to the.westerly flowline of Brittany Drive. Proposed four foot concrete curb inlets will capture stormflows at the intersection of Rumford and Brittany and transfer to an existing 24" RCP under Brittany Drive to spill to a small open channel (channel (3)) and east to Tract "A". The existing pipe under Brittany Drive will receive modification and cleaning to accept stormwater (see sheet 14 of 16). i ' Basin B consists of about 7 developed lots (34 through 40) and undeveloped ground to the north. Water collected in this area will follow natural topography eastward and collect ' in the westerly flowline of Brittany Drive, stormflows will fall northward at the Benson Lane ' intersection. Stormwater will sheet flow eastward through the intersection and collect in the flowlines of Benson Circle (Basin E-1). Basin D ' Basin D flows will follow natural ground to the northeast and collect in the southerly ' flowline of Deerhurst Circle or the flowline of Deerhurst Court:- A 6' concrete sidewalk culvert will collect flows accumulated on the flowline and transfer to a small open channel between ' lots 50 and 51 (channel Section (9)). ' Basin E ' Basin E consists of the area inside Battsford/Deerhurst Circle and Basin E-1, which is ' stormwater collecting to Benson Lane. Stormflows in Basin B and E-1 fall east from Brittany Drive and collect at the end of Benson Lane to a 8 foot concrete sidewalk culvert and an open ' channel (Channel (11)) falling eastto Battsford Circle (Basin E). An eight foot sidewalk culvert is provided at the end of the channel to spill to the west flowline of Battsford Circle. All -15- 1 1 1 1 stormwater collected in Deerhurst Circle and Battsford Circle falls to a 12' pan and drains east across the centerline to a 14' foot sidewalk culvert and then into a shallow channel (channel 0 0)) to Tract A. Basin F and G Basin F consist of the area north of the back of walk on Battsford Circle. This area drains northeast to a shallow channel and then east to the major channel along Lemay Avenue. Basin G consists of a Multi -Family Tract that will be developed in 6-future phase of the development. This area will currently be used for detention storage at the northeast corner of the Tract. Permanent improvements will consist of an outlet structure for the existing triple pipe culverts, channel drop structures and concrete trickle channels. Please refer to sheets 14 and 15 for proposed improvements The existing slope of the pond (4:1) will be extended westward to meet natural ground, future plans call for retaining walls to minimize the slopes and allow room for driveways and garage units of the proposed multi -family development. -16- Off -Site Basins 1 - Numerous developed and undeveloped Basins drain onto the proposed Provincetowne ' P.U.D. Undeveloped Basin C-2 drains to the proposed developed Basin A and flows to ' concentration Point 10. Existing pipes and inlets capture flows and transfer them to channel (2) north of Province Road. Basin C-1 drains to concentration point 11 where existing pipe ' (2-30" RCP's) convey flows to the north and channel (5) in Tract A. ' Undeveloped Basin D-2 flows to the west flowline of Brittany Drive where they are ' intercepted by existing inlets or pipes at Concentration Point 18. All stormwater is collected ' to a 24" RCP that runs along the west and north sides of the developed Redeemer Lutheran", ' -... P.U.D. as shown on sheet 14/16. Collected stormwater in the existing 24" RCP is addeTto' the 100-year_ Historic release from Basin I which is a metered release from a developed detention pond at the northwest corner of the Basin. Channel section (4) has adequate capacity to convey the combined flows (Q100 of 25.9 cfs) to the east and the proposed detention pond. ' Concentration Point 20 reflects the calculated flows from the proposed development ' and the Historic 100-year releases from all upstream basins draining onto the project. Detention pond calculations and proposed improvements are found in Appendix A, sheets 18 through 20. 1 1 -17- Erosion Control Wind Erosion ' This site is located in an area designated as having moderate wind erosion potential. The existing natural grasses provide adequate ground cover for the site in its natural state and the existing erosion from wind appears to be ' minimal. Since this site is being developed with low density and medium density tracts minimal or no overlot grading is anticipated. Only building and ' street areas are being disturbed and permanent improvements will be completed in these areas within two month after.they are exposed. The multi -family area will require silt fence and grasses to provide protection during construction, but ' this area will not be built during the first Phases of construction. Water Erosion This site is located in an area designated as having a high potential for erosion due to stormwater runoff. Examples of this can be seen in existing ' drainage channels on the site. Therefore, straw bales will be placed within the open channels at 100-foot intervals to protect the bed from excess erosion ' during construction. After construction, the swales will be grass -lined and/or adequate erosion revetment will be put in place where the slopes are steeper than 7.5 percent or the banks instable. -18- Conclusions and Recommendations After reviewing the existing drainage information available in this area and surveying the existing site conditions, we present the following recommendations. 1. Existing swales along the north side of Province Road, the west side of South Lemay Avenue and the south side of Trilby Road will be re -sized and seeded where necessary. These channels will be utilized to collect the majority of runoff from this project. 2. Culverts under. South Lemay Avenue at Trilby Road have excess capacity and can adequately convey the major storm runoff for' developed conditions. However, only 94.9 cfs will be released to the downstream channel. 3. All existing storm sewers will be utilized as much as possible. To do so, it will be necessary to retrofit some and remove others. Also, the inlets and outlets will need to be cleaned out and smooth channelized transitions with erosion protection will be installed were necessary. -19- 4. Roadside. ditches, street gutters and backyard swales will be used to convey runoff to existing drainage channels. 5. The majority of grading will be for the streets and swales, however; grading will be needed within the multi -family area to improve drainage (not built in Phase 1). 6. No designated floodplain are located on this site. 7. A blanket drainage easement will cover the low and medium density residential areas (Basins A through G) to allow the runoff to sheet flow to their respective design points. To allow positive drainage away from homes the building pads will be raised with minimum 5% slope away from the home. -20- 1 .. This site is within the Fossil Creek Drainage Basin, and therefore under the jurisdiction of the Fossil Creek Master Drainage Plan. (Reference 10). This master drainage plan does not require on - site detention since there is 'on-line' detention provided along Fossil Creek. The Province/Portner S.I.D. recommends on -site ' detention and the 100-year historic flow will be released. ' Upstream areas draining onto the project will require detention attenuation. Conveyance structures are designed to accept and ' transfer the 100-year historic events from these upstream basins. 1 -21- 1 1 1 1 1. 1 1 REFERENCES 1. Storm Drainage Design Criteria and Construction Standards, City of Fort Collins, May 1984. 2. Urban Storm Drainage Criteria Manual, Urban Drainage and Flood Control District, March 1969. 3. Final Drainage Report for Provincetowne/Portner S.I.D., Parsons & Associates, December 1984. 4. Final Drainage & Erosion Control Report for Redeemer Lutheran Church, Parsons & Associates, Revised May 20, 1992. 5. Final Drainage Report for Somerly at Provincetowne_ P.U.D. Phase I, Parsons & Associates, July 1984. 6. Drainage Study - Portner Estates South Development Phase I, Faulkner -Kellogg & Associates, Inc., July 1985. 7. Final Drainage Report for South Lemay Special Improvement District #86, Engineering Professions, Inc., July 1985. 8. Final Storm Drainage Report for Water Chase P.U.D. Phase One, Parsons & Associates, Revised April 1988. 9. Topography, Northeast Quarter Section 13, Township 6 North, Range 69 West, Arix, April 23, 1981. 10. Fossil Creek Drainage Basin -Master Drainageway Planning Study; Simons, Li and Associates, August 1982. -22- II 1 1 1 APPENDIX A 1 U Z � W ° O > o ' ow W O U Z 1�-I (!) N r/ Z W P Er ' FLO'•i, to Q) C W LL 1 4 W ' xzW LL W U Z � WaU) 1 J m w J C) a a e� 1 m o_ m c 3 rn ' � U m m U � C j N O N a` C C a C E a LL c C `a O c c E `a C c s U O y m O) (O U O m U n N Qrf m C O Ub. O O n to N N [7 !D W (O [�ii17 m m. O O m (+) U O m O C C I . (7 Cl) r N O U r co V .m m C CO M V N V V (h In - M N cr C. C O `o m C (h m O Ufl m O <t m V (n E E V V v N U N Cl) 0 N Cl) (O I-' C O U j m c m rn m m U m N m F E F- N n vi N N ^ O 0 U U m 1 O O O) m v) U C V' (O m N N N N N N N m n O O Cl) a O O O O O N O N O N O N O 0 �? (O O O O O O O O O O L 01 ^ (O 1O O N O O O O co to to N (O U OD J N m HC sf r N m (h r N CO U E O V U n V co 0)R m C.)N N '7 N N N U CD co N CC) N N N a) Cl) O to O O O O O O fO O O O O O O O L 0 0 O 0 0 0 0 �) 0 0 O 0 0 O o m .... In U U N IO U in J C U U U U U U U U U U w U N N N N N N N N N N m U O o 0 0 0 0 0 0 0 0 O U m m m N OD N U m n n O) m m OD v, m 06 m ro u; m Q N M ? m U n 0U (mD w w Z c m 9 Z Z ' N IT m r N C.) C m Q m 3 U U U : O 6 O O m m Z 0 O CO1 C O N C m Om •p N Cl)m R U U N (O (O O a `O J N O O m N m C C U m H L U � II a a _ C '= a ro E m m N O m O C f C c O U m O m m y 0 Z) U o L m .� C LL O E O w E N R v N r M Cc: m R V H 7 a LL + ` _O (L m r II c O E c ~ U C O 0 D 6 s m m m u) E a E E m p ro 3 n Or .. o O O U p o m o� c m mUL N U m E C a C E m m `m c U O H DC ^ N CO V r U ' U w H O Z No Text 1 1 1 1 1 1 1 1 1 1. 1 1 1 1 1 1 1 '1 DRAINAGE CRITERIA MANUAL Af? 30 I— 20 z w U cc 111 a 10 z w a O 5 to w. Cn cc 3 O. V 2 r w I— Q t- 1 5 .1 RUNOFF i son • ONE 00001, mill FA rA M'M C 11 2 .3 .5 1 2' 3 5 VELOCITY IN FEET PER SECOND 10 20 FIGURE 3-2. ESTIMATE OF AVERAGE FLOW VELOCITY FOR USE WITH THE RATIONAL FORMULA. *MOST FREQUENTLY OCCURRING"UNDEVELOPED" LAND SURFACES IN THE DENVER REGION. REFERENCE: "Urban Hydrology For Small Watersheds" Technical Release No. 55, USDA, SCS Jan. 1975. 5-1-84 URBAN DRAINAGE & FLOOD CONTROL DISTRICT 3�� PARSONS & Ir-1- ASSOCIATES ' CONSULTING ENGINEERS . '- FL Cols. Col r & BOS24 ,^ J\ i i 'D C4ENT JOB NO. PROJECT tOV1hCi—�i14..v1 PLAD C_ALrI11 ATIQNS FOR MADE BY GAO DATE /O a 11 13 CHECKED DATE SHEET OF- fd fCS 0L N A� OA w W m 0 AF Cd W cd 3 0 1 m a CD 3 c9 O 0 r O cO c C) 0 O 1 a 0 O C cc c LL a N c c c m t U c LL A U O; m W W U) r n r m M r m r ej W W r N f*� N C U 1. N r R N M m W N '7 'Q r V N O N IT 'N.• N W M O 1, W O 1- n co 0 W r N W (7 r� fl C C r r r n 0 0/ W W 1n 0 r 0 1- W n (O V W Q C C O o ro 'E o rn P% W 1. M W CO Cl) Ol M W O W o m v, r Em Ln LO ri W v co o r of ui w o LO a g o O s{ It r N r W N N N N r r N N M C U j E C r-: W 10 N(51 W r n W W N O 0 r W W Cl) FE M R M C', N .t v N O r N M r M 0 07 0 O U m v N 10 lC N W I� co ID at W N W N W CO) OD O 1 r O CON CO C) 1, V co N (O r 10 1, V I, of 0 N N N N N r r t+j N C7 O V M N N N M N ? 0 N co r N W M W at+� co N O Nt+� N r m m O O O 0 0 0 0 0 0 mOt� O O O O O O 0 O O O O o 0 0 0 o o o o 0 o 0 0 0 0 0 r t wO t0 O O t0 N O O- O L0 O 0 O_ 10 N O N O M O R O W O O R 00 W W W N co W W t0 N v 7 ffOO r 3 W (0 J r N r r m 1E N r W CO V 0 W N W Cl)In r (n O W o W W N I r O/ M M W N 1.: 4 W 6 N 0 (n R m E ` M N r r r IT N r N N r r N N N W c m W N O W co O N O W W O co co W a r V) N N N t� N co W 10 of M IO v)O O O O O O 0 0 0 0 0 0 0 a)-- o0000 00 0 000000 TIC! 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P.U.D. 11-Now93 Velocity and Depth Calculations Formulas based on Open Channel Hydraulics by V.T. Chow, Table 2-1 . Cross Section A 10' Bottom, 4:1 side slopes Area = [10+(y)(4)]y = (10+4y)y WP = 10+2y(1+4^2)^ 1/2 = 10+2y(17)^ 1/2 Radius = Area/WP = (10+4y)y/10+2y(17)^ 1/2 Cross Section B 4' Bottom, 4:1 side slopes Area = [4+(y)(4)]y = (4+4y)y WP = 4+2y(1+4 ^ 2) ^ 1/2 = 4+2y(17) ^ 1/2 Radius = Area/WP = (4+4y)y/4+2y(17) ^ 1/2 Cross Section C T Bottom, 4:1 side slopes Area = [2+(y)(4)]y = (2+4y)y WP = 2+2y(1+4 ^ 2) ^ 1/2 = 2+2y(17) ^ 1/2 Radius = Area/WP = (2+4y)y/2+2y(17) ^ 1/2 Cross Section D "W Bottom, 4:1 side slopes Area = [(y)(4)]y = 4y ^ 2 WP = 2y(1+4^2)^1/2=2y(17)^1/2 Radius = Area/WP = 4y ^ 2/2y(17) ^ 1/2 Froude # = F = V/(gy)^ 1/2 t 1 1 1 1 1 Pr-ovinctowne P.U.D. 22-Dec-93 Velocity and Depth Calculations Formulas based on Open Channel Hydraulics by V.T. Chow, Table 2-1 Cross Section A 10' Bottom, 4:1 side slopes Area = [10+(y)(4)]y = (10+4y)y WP = 10+2y(1+4^2)^ 1/2 = 10+2y(17)^ 1/2 Radius = Area/WP = (10+4y)y/10+2y(17)^ 1/2 Cross Section B 4' Bottom, 4:1 side slopes Area = [4+(y)(4)]y = (4+4y)y WP = 4+2y(1+4^2)^1/2=4+2y(17)^1/2 Radius = Area/WP = (4+4y)y/4+2y(17)^ 1/2 Cross Section C 2' Bottom, 4:1 side slopes Area = [2+(y)(4)]y = (2+4y)y WP = 2+2y(1+4^2)^1/2=2+2y(17)^1/2 Radius = Area/WP = (2+4y)y/2+2y(17) ^ 1/2 Cross Section D "V" Bottom, 4:1 side slopes Area = [(y)(4)]y = 4y^ 2 WP = 2y(1+4^2)^1/2=2y(17)^1/2 Radius = Area/WP = 4y^ 2/2y(17) ^ 1/2 Froude # = F = V/ (gy) ^ 1/2 ' Provinctowne P.U.D. 22-Dec-s3 MAJOR STORM VELOCITY AND DEPTH CALCULATIONS Outfall Channel for all upstream Basins (100-yr historic release) #1 Cross Section B f ' S = 0.009 Q'n/1.486'S^ 1/2 = 23.56103 Q = 94.9 ' n = 0.035 Q'n/1.486'S^1/2 Depth WP Area AR^213 j Velocity 23.56103 1 12.25 8.00 6.0230 ' 23.56103 2 18.49 20.00 21.0728 23.56103 2.2 20.14 23.76 26.5267 23.56103 2.1 19.32 21.84 23.7026 ' 23.56103 2.09 19.235 21.652 23.4310 4.38 fps Froude # 0.53 Swale on north side of Province Road ' # 2 Cross Section C S = 0.0274 Q'n/1.486'S^1/2 = 11.58646 ' Q = 47.5 n = 0.06 Q'n/1.486'S ^ 1/2 Depth WP Area 11.58646 1 10.25 6.00 11.58646 2 18.49 20.00 11.58646 1.8 16.84 16.56 ' 11.58646 1.75 16.43 15.75 11.58646 1.78 16.678 16.234 ' Swale running between acre lots & 1/3 acre lots # 3 Cross Section C S = 0.0322 Q'n/1.486'S^ 1/2 = 13.56819 Q = 60.3 n = 0.06 ' Q'n/1.486'S^1/2 Depth WP Area 13.56819 1 10.25 6.00 ' 13.56819 2 18.49 20.00 13.56819 1.7 16.02 14.96 13.56819 1.6 15.19 13.44 13.56819 1.65 15.606 14.190 AR ^ 2/3 Velocity 2.4694 15.6831 11.8413 10.9842 11.4936 2.93 fps Froude # 0.39 AR ^ 2/3 Velocity 4.1921 21.0782 14.2902 12.3796 13.3138 4.25 fps Froude # 0.58 Swale on north side of multi -family tract # q Cross Section C S = 0.04 Q'n/1.486'S ^ 1/2 = 5.228802 ' Q = 25.9 q = 0.06 1'. Q'n/1.486'S ^ 1/2 Depth WP Area 5.228802 1 10.25 6.00 5.228802 1.1 11.07 7.04 5.228802 1.2 11.90 8.16 5.228802 1.15 11.48 7.59 5.228802 1.11 11.153' 7.148 Swale at south end of Tract A ' #5 S = 0.0045 Q'n/1.486'S ^ 1/2 = 59.8893 Q = 99.5 n = 0.06 Cross Section A Q'n/1.486'S^1/2 Depth WP Area 59.8893 1 18.25 14.00 59.8893 2 26.49 36.00 59.8893 2.1 27.32 38.64 59.8893 2.05 26.90 37.31 ' 59.8893 2.07 27.07 37.84 ' Tract A Channel with grass lining # 6 Cross Section A ' S = 0.02 Q'n/1.486'S ^ 1/2 = 48.73612 Q = 170.7 n = 0.06 ' Q'n/1.486'S^1/2 Depth WP Area 48.73612 1 18.25 14.00 48.73612 2 26.49 36.00 48.73612 1.7 24.02 28.56 48.73612 - 1.8 -24.84 30.96 48.73612 1.85 25.26 32.19 ' Channel on sloped riprap drop (grouted) # 7 Cross Section A S = 0.25 Q'n/1.486'S^1/2 = 9.64926 Q = 170.7 n = 0.042 Q'n/1.486'S^1/2 Depth WP Area ' 9.64926 1 18.25 14.00 9.64926 0.6 14.95 7.44 9.64926 0.7 15.77 8.96 ' 9.64926 0.8 16.60 10.56 9.64926 0.69 15.69 8.80 1 AR ^ 2/3 4.1921 5.1981 6.3389 5.7513 5.3060 Froude # 0.61 q*_ fps AR ^ 2/3 Velocity 17.2566 56.2522 61.4854 58.8364 59.8882 "2.63 fps Froude # 0.32 AR ^ 2/3 Velocity 17.2566 56.2522 42.0745 46.5515 48.9824 5.30 fps Froude # 0.69 AR^2/3 Velocity 17.2566 7.7892 9.8556 12.1201 9.6401 19.39 fps Froude # 4.11 1 1 1 1 1 Swale between lots 15 & 16 #8 S = 0.0308 Q = 9.3 n = 0.06 Swale between lots 50 & 51 #9 S = 0.06 Q = 15.3 n = 0.06 Cross Section D Q'n/1.486'S^ 1/2 = 2.139637 Q'n/1.486'S^ 1/2 Depth WP Area 2.139637 0.5 4.12 0.50 2.139637 0.8 6.60 2.05 2.139637 0.9 7.42 2.92 2.139637 1 8.25 4.00 2.139637 1 . .8.25 4.00 Q'n/1.486'S ^ 1/2 = 2.522018 Cross Section D Q'n/1.486'S ^ 1/2 Depth WP Area 2.522018 1 8.25 4.00 2.522018 1.5 12.37 13.50 2.522018 1.1 9.07 5.32 2.522018 1.05 8.66 4.63 2.522018 1.04 8.58 4.50 awaie oetween lots �4 ac» # 10 S = 0.0333 Q = 57.8 n = 0.06 Swale between lots 87 & 88 # 11 S = 0.0519 Q = 19.2 n = 0.06 Cross Section C Q'n/1.486'S ^ 1/2 = 12.78905 Q'n/1.486'S ^ 1/2 Depth WP Area 12.78905 1 10.25 6.00 12.78905 1.3 12.72 9.36 12.78905 1.8 16.84 16.56 12.78905 1.6 15.19 13.44 12.78905 1.62 15.359 13.738 Cross Section D Q'n/1.486'S^1/2 = 3.402906 AR^2/3 Velocity 0.0933 0.7833 1.3290 2.1299 2.1299 2.33 fps Froude # 0.41 AR ^ 2/3 Velocity 2.1299 12.9472 3.2600 2.6488 2.5379 3.40 fps Froude # 0.59 AR^2/3 Velocity 4.1921 7.6212 16.3729 12.3796 12.7483 4.21 fps Froude # 0.58 Q'n/1.486'S^1/2 Depth WP Area AR^2/3 Velocity 3.402906 0.8 6.60 2.05 0.7833 3.402906 0.9 7.42 2.92 1.3290 3.402906 1 8.25 4.00 2.1299 3.402906 1.1 9.07 5.32 3.2600 3.402906 1.11 9.15 5.47 3.3943 3.51 fps Froude # 0.59 ' ' ' ' ' Swale along south side of church property and through Tract B # 12 S = 0.0459 Q'n/1.486'S^ 1/2 = 3.109639 Q = 16.5 n = 0.06 Q•n/1.486•S^ 1/2 Depth 3.109639 1 3.109639 1.5 3.109639 1.25 3.109639 1.1 3.109639 1.09 WP 8.25 12.37 10.31 9.07 8.99 Cross Section D Area 4.00 13.50 7.81 5.32 5.18 AR^2/3 2.1299 12.9472 5.7615 3.2600 3.1298 Froude # j I Velocity 3.19 0.54 fps Swale at NW toner of Province & Brittany ' # 13 Cross Section C S = 0.012 Q•n/1.486•S^ 1/2 = 17.50796 Q = 47.5 ' n = 0.06 Q'n/1.486'S^ 1/2 Depth WP Area AR^2/3 Velocity ' 17.50796 1 10.25 6.00 4.1921 17.50796 1.3 12.72 9.36 7.6212 17.50796 1.8 16.84 16.56 16.3729 ' 17.50796 1.9 17.67 18.24 18.6337 17.50796 1.85 17.255 17.39 17.4807 2.73 fps Froude # 0.35 1 1 1 1 1 Pcovinctowne P.U.D. 22-oec-93 2-YR Velocity and Depth Calculations Formulas based on Open Channel Hydraulics by V.T. Chow, Table 2-1 Cross Section A 10' Bottom, 4:1 side slopes Area = [10+(y)(4)]y = (10+4y)y WP = 10+2y(1+4^2)^ 1/2 = 10+2y(17)^ 1/2 Radius = Area/WP = (10+4y)y/10+2y(17) ^ 1/2 Cross Section B 4' Bottom, 4:1 side slopes Area = [4+(y)(4)]y = (4+4y)y WP = 4+2y(1+4 ^ 2) ^ 1/2 = 4+2y(17) ^ 1/2 Radius = Area/WP = (4+4y)y/4+2y(17) ^ 1/2 Cross Section C 2' Bottom, 4:1 side slopes Area = [2+(y)(4)]y = (2+4y)y WP = 2+2y(1+4^2)^1/2=2+2y(17)^1/2 Radius = Area/WP = (2+4y)y/2+2y(17)^ 1/2 Cross Section D "V" Bottom, 4:1 side slopes Area = [(y)(4)]y = 4y ^ 2 WP = 2y(1+4^2)^1/2=2y(17)^1/2 Radius = Area/WP = 4y^2/2y(17)^ 1/2 Froude # = F = V/ (gy) ^ 1/2 1 1 1 1 Provinctowne P.U.D. 22-Dec-93 MINOR STORM VELOCITY AND DEPTH CALCULATIONS Outfall Channel for all upstream Basins (2-yr historic release) #1 Cross Section B S = 0.009 Q*n/1.486*S ^ 1/2 = 11.71844 Q = 47.2 n = 0.035 Q*n/1.486*S^1/2 Depth WP Area AR^2/3 Velocity I 11.71844 1 12.25 8.00 6.0239 11.71844 1.2 11.90 8.16 6.3468 11.71844 1.5 14.37 12.00 10.6416 11.71844 1.6 15.19 13.44 12.3846 11.71844 1.56 14.864 12.854 11.6679 3.67 fps Froude # 0.52 Swale on north side of Province Road # 2 Cross Section C S = 0.0274 Q*n/1.486*S ^ 1/2 = 3.146639 Q = 12.9 n = 0.06 Q*n/1.486*S ^ 1/2 Depth WP Area AR^2/3 Velocity. 3.146639 2 18.49 20.00 15.6831 3.146639 1.5 14.37 12.00 7.2815 3.146639 1.2 11.90 8.16 4.0157 3.146639 1.1 11.07 7.04 3.1941 3.146639 1.09 10.988 6.932 3.1074 1.86 fps Froude # 0.31 Swale running between acre lots & 1/3 acre lots(sum of DP 13 & 12A) # 3 Cross Section C S = 0.0322 Q*n/1.486*S^ 1/2 = 3.55518 Q = 15.8 n = 0.06 Q*n/1.486*S^I/2 Depth WP Area AR^2/3 Velocity 3.55518 1 10.25 6.00 4.1921 3.55518 2 18.49 20.00 21.0782 3.55518 0.8 8.60 4.16 2.5578 3.55518 0.9 9.42 5.04 3.3143 3.55518 0.93 9.669 5.320 3.5646 2.97 fps Froude # 0.54 ' Swale on north side of multi -family tract (sum of DP 18 & 19) #4 ' S = 0.04 Q'n/1.486'S^1/2 = 1.41319 Q = 7 n = 0.06 ' Q*n/1.486'S^1/2 Depth 1.41319 1 1.41319 1.41319 0.8 0.6 1.41319 0.7 1.41319 0.62 Cross Section C WP Area 10.25 6.00 8.60 4.16 6.95 2.64 7.77 3.36 7.113 2.778 Swale at south end of Tract A ' # 5 Cross Section A S = 0.0045 Q*n/1.486'S ^ 1/2 = 16.31156 Q = 27.1 ' n = 0.06 Q*n/1.486'S ^ 1/2 Depth WP Area ' 16.31156 1 18.25 14.00 16.31156 2 26.49 36.00 16.31156 0.9 17.42 12.24 16.31156 0.94 17.75 12.93 16.31156 0.97 18.00 13.46 . Tract A Channel with grass lining #6 S = 0.02 Q*n/1.486'S ^ 1/2 = 13.47595 Q = 47.2 n = 0.06 ' Q*n/1.486*S^1/2 Depth 13.47595 1 13.47595 2 ' 13.47595 0.5 13.47595 0.8 ' 13.47595 0.86 Channel on sloped riprap drop (grouted) ' #7 S = 0.21 Q*n/1.486*S^ 1/2 = 2.668102 ' Q = 47.2 n = 0.042 Q*n/1.486*S^ 1/2 Depth ' 2.668102 0.4 2.668102 0.2 ' 2.668102 2.668102 0.3 0.31 2.668102 0.29 Cross Section A WP Area 18.25 14.00 26.49 36.00 14.12 6.00 16.60 10.56 17.09 11.56 Cross Section A AR^2/3 Velocity f1 4.1921 2.5578 1.3805 j 1.9157 1.4793 2.52 fps Froude # 0.56 AR^2/3 Velocity 17.2566 56.2522 14.5859 15.6293 16.4336 2.01 fps Froude # 0.36 AR ^ 2/3 Velocity 17.2566 56.2522 5.9189 12.1201 13.5752 4.08 fps Froude # 0.78 WP Area AR ^ 2/3 Velocity 13.30 4.64 4.2453 11.65 2.16 1.5201 12.47 3.36 2.7735 12.56 3.48 2.9113 12.39 3.24 2.6379 14.58 fps Froude # 4.77 i ' Swale between lots 15 i& 16 (with new walkway) # 8 S = 0.08 Q'n/1.486'S ^ 1/2 = 0.356884 Q = 2.5 it = 0.06 ... Q'n/1.486*S^1/2 Depth 0.356884 0.5 0.356884 0.8 0.356884 0.6 0.356884 0.7 0.356884 0.67 WP 4.12 6.60 4.95 5.77 5.52 Cross Section D . Area 0.50 2.05 0.86 1.37 1.20 AR^2/3 0.0933 0.7833 0.2138 0.4293 0.3522 Froude # Veloci y 2'08 fps 0.45 Swale between lots 50 & 51 ' # 9 Cross Section D S = 0.06 Q*n/1.486*S ^ 1/2 = 0.675835 Q = 4.1 ' n = 0.06 Q*n/1.486*S^1/2 Depth WP Area AR^2/3 Velocity ' 0.675835 1 8.25 4.00 2.1299 0.675835 1.5 12.37 13.50 12.9472 0.675835 0.6 4.95 0.86 0.2138 ' 0.675835 0.8 6.60 2.05 0.7833 0.675835 0.77 6.35 1.83 0.6595 2.2.5 fps Froude # 0.45 ' Swale between lots 54 & 55 # 10 Cross Section C S = 0.0333 Q*n/1.486*S^ 1/2 = 2.057753 Q = 9.3 n = 0.06 Q*n/1.486*S^1/2 Depth WP Area AR^2/3 Velocity 2.057753 1 10.25 6.00 4.1921 ' 2.057753 0.5 6.12 2.00 0.9450 2.057753 0.7 7.77 3.36 1.9157 2.057753 0.8 8.60 4.16 2.5578 ' 2.057753 0.72 7.937 3.514 2.0353 2.65 fps Froude # 0.55 Swale between lots 87 & 88 # 11 Cross Section D ' S = 0.0519 Q*n/1.486*S^1/2 = 0.903897 ' Q = 5.1 n = 0.06 Q*n/1.486*S^1/2 Depth WP Area AR^2/3 Velocity ' 0.903897 0.5 4.12 0.50 0.0933 0.903897 0.9 7.42 2.92 1.3290 0.903897 1 8.25 4.00 2.1299 ' 0.903897 0.8 6.60 2.05 0.7833 0.903897 0.83 6.84 2.29 0.9242 2.2-3 fps ' Froude # 0.43 i /�/ Swale along'south sid6of church property and through Tract B # 12 -Cross Section D ' S _= 0.0459 Q*n/1.486•S ^ 1/2 0 829237 Q = 4.4- - '. n = 0.06 . ' Q*n/1.486*S^1/2 Depth WP Area AR^2/3 Velocity 0.829237 1 8.2.5 4.00 2.1299 ' 0.829237 0.5 0.829237 0.7 4.12 .5.77 0.50 1.37 0.0933 0.4293 0.829237 0.8 6.60 2.0.5 0.7833 0.829237 0.81 6.68 2.13 0.8282 2.07 fps ' Froude # 0.41 Swale at the NW corner Province & Brittany ' # 13 Cross Section C S = 0.012 Q*n/1.486*S ^ 1/2 = 4.754792 Q = 12.9 ' n = 0.06 Q*n/1.486*S ^ 1/2 Depth WP Area AR ^ 2/3 Velocity ' 4.754792 1 10.25 6.00 4.1921 4.754792 0.8 8.60 4.16 2.5578 4.754792 0.9 9.42 5.04 3.3143 ' 4.754792 1.1 11.07 7.04 5.1981 4.754792 1.05 10.659 6.510 4.6787 1.98 fps ' Froude # 0.34 1 1 1 1 1 1 1 1 1 t 1 1 DETENTION VOLUME REQUIREMENTS Page. 100 Year Event q of Pages Project Number: Project Title: Date: 92.21-KEN PROV/NCETOWNE P.U.D. 07-Oct-93 Estimator: G.A.ODEHNAL File: V01-100.W01 Problem: Determine the total volume of detention required for the proposed development which consists of approximately 70.67 acres. All off -site basins will provide their own detention storage and release only the Historic 100 year event. Given: a) Fully developed conditions b) The historic 100 year release = 94.9 cfs c) Basins Included: A, B, B-1, C, C3, D, E, E-1, F, G, & J d) Mass Diagram Method of Detention Calculation Composite'C'=[(52.91)(0.45)+(6.20)(0.70)+(7.76)(0.28)+(3.80)(0.95)j/70.67 = 0.480 CCfA = (0.48)(1.25)( 70.67 ac) = 42.40 Time: 100 yr. freq. Time: Acumulated Outfall Volume: Storage Required: min. CCfA Inten, seconds Vol. (ft^3) a= 94.9 cfs ft ^3 Ac-Ft 5 42.40 8.12 300 103,291 28,470 74,821 1.7177 10 42.40 7.15 600 181,905 56,940 124,965 2.8688 15 42.40 6.00 900 228,971 85,410 143,561 3.2957 20 42.40 5.20 1200 264,588 113,880 150,708 3.4598 _ - 30 42.40 4.20 1800 320,559 170,820 149,739 3.4375, 40 42.40 3.52 2400 358,212 227,760 130,452 2.9946" 50 42.40 3.08 3000 391,794 284,700 107,094 2.4586: -- 60 42.40 2.62 3600 399,936 341,640 58,296 1.3383 90 142.40 1.88 1 5400 1 430,465 1 512,460 1- Maximum Volume Required: 150,708 ft^ 3 or 3.4598 Ac: Ft. CLIENT JOB NO. PROJECT CALCULATIONS FOR L MADE BYGA0 DATE CHECKED- DATE SHEET OF 116- I I I F I I 1) I I I I F I 1 m CLIENT JOB NO. PROJECT CALCULATIONS FOR DATE 0/1 v MADE BY CHECKED_ DATE_ SHEET -A- OF I I I I I 1) I I I I I I PARSONS & ASSOCIATES. - CONSULTING ENGINEERS ' _ FL Conn,, Colorado 90524 1 i i� 1 CLIENT �/. / G IL.0 ``-' JOB NO �/� A I ��✓ PROJECT, ���,froYlf�Ct W�.C_.. CALCULATIONS FOR %- MADEBY `FAO DAT IJI1 1q 3 CHECKED - DATE SHEET �/ L�� � �OF PARSONS & CLIENT JOB NO. ASSOCIATES PROJECT ram% 0+f� CALCULATIONS FOR CONSULTING ENGINEERS ^ -y 1.. , FL ��. CAb�ado 805� MADE BY �� DAT - �� � 3 3 CHECKED DATE SHEET 1 I 1 1 1 1 1 1 1) 1 u 1 1 No Text jPARSONS & CLIENT JOB NO. ASSOCIATES PROJECT I Y�IhCL'�w1 CALCULATIONS FOR CONSULTING ENGINEERS � Il - FL Callas, Colorado 80524 MADE BY ��� DATE �� CHECKED DATE - SHEET raOF � 1 1 1 i 1 1 1) 1 1 1 1 1 1 PARSONS & ASSOCIATES CONSULTING ENGINEERS FL Collm. Colorado 80520 i 1 1 1 1 1 1 1 1 1 1 1 1 CLIENT '/�_�� JOB NO. 1 ^! � — ' ^ I "�/ /] PROJECT I m;",e-� ��q� CALCULATIONS FOR �J MADEBY C A`O DATE 9/I i3 CHECKED 'DATE SHEET ^� OF-3—S CLIENT ,.. I LLe-(_.�,' JOB NO. 1 2 • 2 KLI ��PROJECT vW�'�� CA CALCULATIONS FOR , I MADE BY GAO DATE �! /93 CHECKED DATE SHEET �^ I 1 i 1 1 1 1_D 1 1 1 1 1 1 1.0 1 .9 .8 .7 ' .6 .5 w � .4 z 0 z z .3 w a 0 o..25 t- co w x .2 .15 12 II 10 8 10 6 u_ 9 0 4 �. -F w a e w 3 a � 7 Pat`/ ; 2� `��s/LF _T z t c� z xample Part a I0 z ' O 8 ��j�lF 5.5 a - o w co .6 �'- 5 = z 0 z Z z w .4 H x 4.5 z. ao .3 w w _ 4 t 0 0 0 _ F, .2 z z � o 3.5 z w z w >. a 0 I o: 0 U. .08 w 3 ►- 0 .06 0 = co 0 u_ z w = rc .04 0: 2.5 w w 2 °' .03 a �- � 3 .02 0 a = cai a.. w .01 a w 0 0 1.5 ------ -- -- Yo '- .10 � D.uO =aac(ljr-C-Ie44) N . 0,50 1.2 5 4 3 2 1.5 1.0 .9 .8 .7 .6 .5 ,4 .3 .25 .2 .15 Figure 5-2 NOMOGRPAH FOR CAPACITY OF CURB OPENING INLETS IN SUMPS, DEPRESSION DEPTH 2" Adapted from Bureau of Public Roads Nomograph 9 0.6)4 ' MAY 1984 5-10T `IoJ l DESIGNOCRITERIA 1 .. CLIENT IJ ikD ��/ JOB NO. !—I i�At FPARSONS &c /��/ L '^�/ ASSOCIATES. PROJECT 1 wv'�G~'W�' �Lv CALCULATIONS FOR - - :, CONSULTING ENGINEERS - Q- ONSUkCot' C.G ENG NIEER MADE BY. GAO DAT 13 CHECKED DATE SHEET � OF 3�+ .1 1.. 1 11 1 PARSONS & a ASSOCIATES CONSULTING ENGINEERS FL C Iles. Cokes do W524 1 1 1 1 1 1 1� 1 i 1 1 1 1 1 CLIENT JOB NO. 92-7- 11 KE V PROJECT - rWI'• ?L)D. _..__CALCULATIONS FOR �� '"✓uc l-{y � J�1"�� ����M Al /� 1 MADE BY GA DATEI 14) CHECKED DATE SHEET OF3%S' ����I`/ 2-^' ktA A CLIENT JOB NyO 1 ' tfPARSONS ASSOCIATES ' CONSULTING ENGINEERS FL C.Bi Cotwm6 80524 PROJECT I/YjVin t yp}M MADE BY 17L� DATES ��O CALCULATIONS FOR 2'q3 �Q CHECKED DATE SHEET, M OF_3�T— C 1 1 "a?PARSONS & CLIENT JOB NO. ASSOCIATES PROJE( CALCULATIONS FOR CONSULTING ENGINEERS FL Collm, Colorado BOS24 MADE BY GAO DATE 10/dl" CHECKEDDATESHEET19 OF I 11 I I I 1) 11 I I I 1 I 1 11 1 i 1 1) 1 1 i 1 1 1 RPARSONS & .ASSOCIATES CONSULTING ENGINEERS 1. FL Collm, Cal..& 80524 F I I I I I U I I I I 1 CLIENT JOB NO. RPROJECT CALCULATIONS FOR MADE BY GAQ DATE 10 . /2-7.h 3 CHECKED- DATE- SHEET -IL- OFJ-5 1 1 1 1 1 1 1 1 1 1 1 1 1 i 1 1 1.. 1 1 PARSONS & Ir" l ASSOCIATES CONSULTING ENGINEERS FL c u,,6 C,6,&& SOS24 CLIENT I-��1 JOB NO. ! PROJECT aVo11 nci7c�Wf<.. CALCULATIONS FOR MADE BYO DATE IO w 3 CHECKED DATE SHEET Provinctowne P.U-D - 27-opt-93 31� 3 CIAO Velocity and Depth Calculations Formulas based on Open Channel Hydraulics by V.T. Chow, Table 2-1 1 Cross Section A 10' Bottom, 4:1 side slopes Area = [10+(y)(4)]y = (10+4y)y WP = 10+2y(1+4^2)^1/2=10+2y(17)^1/2 Radius = Area/WP = (10+4y)y/10+2y(17)^ 1/2 1 Channel on sloped riprap drop (grouted) I ^ Cross Section A S = 0.25 Q•n/1.486•S 1/2 9.64926 Q = 170.7 I n = 0.042 Q•n/1.486•S^1/2 Depth WP Area AR^2/3 Velocity 9.64926 0.5 14.12 6.00 5.9189 9.64926 0.6 14.95 7.44 7.7892 9.64926 0.7 15.77 8.96 9.8556 9.64926 0.8 16.60 iM6 121201 9.64926 0.69 15.69- 8.80 9.6401 1939 fps Froude # 4.11 ' Channel in tract A (w/ grass lining) Cross Section A S = 0.02 Q'n/1.486•S^1/2 48.73612 Q = 170.7 n = 0.06 Q•n/1.486'S-1/2 Depth WP Area AR^2/3 Velocity 48.73612 1 18.25 14.00 17.2566 48.73612 2 26.49 36.00 56.2522 48.73612 1.7 24.02 28.56 42.0745 48.73612 1.8 24.84 30.96 46.5515 48.73612 1.85 25.26 32.19 48.8824 5.30 fps Froude # 0.69 i No Text 14 HYDRAULIC DESIGN OF STILLING BASINS AND ENERGY DfSSIPATORS I G� L D¢ r. ■■■■■■■■■■■■■■■■■■■■a��■■■■■■■■■■■■■■■■■■ ■■■■■■■■■■sCC3C=IwC�C:�t:NIL!L�lN■■■■■■■■■■■■ ■■■■■■■■►■�I�a■EEQ�a■■■r�■■Elaraw■■■■■■■■■■■■■ ��wv��w.�aww w7��O-!� MINI MINI!■■! ■ MINI! ME No ■■■ii■■■■■■0■.�■■■ !■■■l'1■��■!IElE■!.■..!■■■!■■■!■■■!■!!■!.� ■ENE■►t, . O1■■■raEEE■ENE■■■■■!■■■■■■■!.!■■!!� ■■■■ ■■■■■■. ■■■■DJ:O■■1■■NIB■■■■■■■■■■■■■■■■■■■■■.■■!■■■ ■■■■►al■■■1■■■■M�■■■.�■��■■■■■■■■■■■■■■■■■■■ ■■■■rANlE1■Ellw!■■■■■■■!■■■■—..iz.■■■■■■■■■!! ■■■■1N■■ ■EE■E■L��■■■■■■■■■�©J■■■■■■■■■fiC!l. ■■■I�■■■II■■OMEN ■■■■■■■■■■■NE■■■■■■■■■■■■■ ■■■■■WW •. EE■■■E■EE■N! O _ O ■■■■�■■ NE■EE■E■ENE! ■EE■IIN■■1■■■■!■■■■■■■■■■■■ ■■ NI■■■■MINI■■■■■Tech. ME NONE ■EMENEENNEEME ME!■,NN■ ■.■MMMIM C■■ ■■■■■■■■■E■EN■EEE■■■■■ ■ ■■■EE■■■■E■E■EE■N■.N■■■E.■■■EE. ■E■.1■EE ME BEEN ■■■■■■■■■■■■■■■■■■■.■■■...■■. ...■■■..1......■...■..■.■.■■■■■■■■■■E■■■i ■EN■E■■■1■EN■■EE■E■N■N■■E■E!N!■!EN■N!!E!■ ■■NE■EE■1■E■■ENE■■■EN■E■E■■■E■■■E■EE■■■E■. MIN■■■■E■1■■■■NEE■N■EEE■E■■EEEEE■■■E■■■■■ ■E■■NEE■1■■!ElENlEN■■■E■■■N■EE■■1•���■�■■ .� In 16 Is Zo V, F= , FiGuna 7.—Length of jump in terms of D2 (Basin n. the Federal Institute of Technology, Zurich, computations, and the symbols may be defined by Switzerland, on a flume 0.6 of a meter wide and consulting the specific energy diagram in Figure 4. 7 meters long. The curve numbers are the same Column 14 lists the total energy, .E,, entering the as the reference numbers in the 'Bibliography" jump at Section 1 for each test. This is simply which refer to the work. the depth of flow, D,, plus the velocity head As can be observed from Figure 7, the test re- computed at the point of measurement. The sults from Flumes B, C, D, E, and F plot suffi- energy leaving the jump, which is the depth of ciently well to,.es.tablish.a single curve., The five , ..flovr. plus the velocity head at Section 2, is to points from Flume A, denoted by squares, appear lated in Column 15. The differences in the somewhat erratic and .plot to the right of the values of Columns 14 and 15' constitute the loss general curve. Henceforth, reference to Figure 7 of energy,. in feet of water, attributed to the will concern only the recommended curve, which conversion, . Column 16. Column 18 lists the is considered applicable for general use. percentage of energy lost in the jump, EL, to the total energy entering the jump, El. This per - Energy Absorption in jump centage is plotted with respect to the Froude number and is shown as the curve to the left on With the experimental information available, Figure 8. For a Froude number of 2.0, which the energy absorbed in the jump may be com- would correspond to a relatively thick jet entering puted. Columns 14 through 18, Table 1, list the the jump at low velocity, the curve shows the ' APPENDIX B r' ■ 1 1 1 1 RAINFALL PERFORMANCE STANDARD EVALUATION PROJECT: U I) I ( STANDARD FORM A COMPLETED BY: &AG DATE: q 2 93 DEVELOPED SUBBAgIN ERODIBILITY ZONE Asb (ac) Lsb (ft) Ssb M Lb (feet) Sb PS 8.3C9 i`00 LM _ I l C C- 60 ZoO z 3 �-1 Soo. 3.5 Z 0 �{ �LO 5.6 zoM 01 ' MARCH 1991 8-14 DESIGN CRITERIA 1 [I 1 1 1 1 EFFECTIVENESS CALCULATIONS PROJECT: I in�o� 7tAD - J1j-54 R STANDARD FORM B COMPLETED BY: GA DATE: 10 / 93 Erosion Control C-Factor P-Factor MethodValue Value Comment" LL 5- I MAJOR PS SUB AREA BASIN BASIN (Ac) CALCULATIONS g3; 2 g 3, V,j 01.7-5(.OlA C : rrP,{ it �L.� (0 102�c 1.0)�C)K- h I Z•U"l .� ��b of Xp° c(,s4/,,LtA .. - - �,.,T)i .�"' �(2:5Z)(o.oCo),{•.(, 11)( lo•.2.Z)��� •vzi .. . 0.10 �= 1-00 El - (p• to x, o)] x lo0 4 q o. ot Ok Acnl( �itPl. C�1Z 1urrW/� y./�� -75 °b oT ArAk u.'�+�t�.rh� I �- 7 `( A L. °C(y•z!>)(•O(.)� 11.05 '096 wY D P = L( y .90) (. So) . + (2. I5)(. aq/p . 05 p .8o 1 - (0.098x 0 . B0)7 x 100 = 9 2. 0 MARCH 1991 8-15 DESIGN CRITERIA 1 1 1 _1 1 1 1 1 1 1 1 EFFECTIVENESS CALCULATIONS PROJECT: ' resin �h� PUQ - 01� STANDARD FORM B COMPLETED BY: CIA 6 DATE: 91 jJ3 Erosion Control C-Factor P-Factor Method Value Value Comi/nent �50-1 < t 0.060 c G,j� Cyr 0.11 1.0 s�rr w �� Les 1 . 0 0. ao on - 51.4c c.k--,nmis MAJOR PS SUB AREA BASIN ($) BASIN (Ac) CALCULATIONS g3.2 D z(.l8 y0 o� -arm d)s�u- (Gs:). /.�7 Cft U3,do, I Ac.. C L�?'� f\ II.IV Irr✓C �'^fl A`__ 2V1� I I 001 U��✓� IY�� 1�,g6 �L ��� .,� s << z.�ox.o�,►o.�)c. l l>>/ 5V = o ►o �D1 p, are MARCH 1991 8-15 DESIGN CRITERIA EFFECTIVENESS CALCULATIONS 1 1 1 1 1 1 1 1 1 1 1 1 1 1 i PROJECT: I r inu ohs )-"UQ - 1,j-�4 R ki STANDARD FORM B COMPLETED BY: Gfl0 DATE: I lq3 Erosion Control C-Factor P-Factor Method Value Value Comment 0.064 ', p Oc I (i 44 r&A GIKGs — GisT;..y C7rrq Corr O- II 1.0 1.0 Q. SO onJJ- MAJOR PS SUB AREA BASIN (%) BASIN (A—c/)) CALCULATIONS y,tv rI ' �l7"!o Of 0-9,q 3 , 7 (D A- �JfrJ� "C' = T(0ILI )C.OG) i (1-7G)(.11)1/i Zp - 0.10 (1.00 j(.lo)]X)OV S `0� -0k-- --G 151. of au. -� x „obis+kr 6ar.L - y , cg5 AL WfC� H C� �.55) 0&) 4 (�.(o�>(,It,1_/ c 09b WEd„I�^ ` ,00 �F 1- ft 00)( 90, Z% Ole 1 MARCH 1991 8-15 I5 A( - DESIGN CRITERIA t . 1 1 1 1 1 0, W R, VI TABLE I CONSTRUCTION SEQUENCE PROJECT: PROVINCETOXNE P.U.D. STANDARD FORM C SEQUENCE FOR 1993 ONLY COMPLETED BY: C.A. ODENNAL DATE: 9103193 Indicate by use of a bar line or symbols when erosion control measures will be installed. Major modifications to an approved schedule may require submitting a new schedule for approval by the City Engineer. ' YEAR 1993 f994 MONTH NOV. DEC. ✓AN. 1 FEB. MAR APR MAY IERLOT GRADING & UTILITIES ND EROSION CONTROL Soil Roughing Perimeter Barrier Additional Barriers Vegetative Methods Soil Sealant Other dNFALL EROSION CONTROL TRUCTURAL: Sediment Trap/ Basin Inlet Filters Straw Barriers Silt Fence Barriers Sand Bags Bare Soil Preparation Contour Furrows Terracin Asphalt Concrete Paving Other GETATIVE: Permanent Seed Planting Mulching/ Sealant Temporary Seed Planting Sod Installation Nettings/ Mats/ Blankets Other TABLE 2 EROSION CONTROL METHODS EROSION CONTROL METHOD C—FACTOR VALUE P—FACTOR VALUE COMMENTS STRAW BALE DIKE 1.0 0.80 ALL CHANNELS IN PROJECT ASPHALT PAVEMENT 0.01 1.00 ALL ROADWAYS SEED/ STRAW MULCH 0.06 1.00 ALL DISTURBED AREAS (2 TONS/ ACRE) ESTABLISHED GRASSES 0.05 1.00 UNDISTURBED GRASSES ENGINEER'S COST ESTIMATE Page: FINAL 6 of 6 Pages Project Number: Project Title: Date: 9221-KEN PROV/NCETOWNE P.U.D. 01-Nov-93 Estimator: G.A.ODEHNAL File: PROV-ERO.WQ Item #1: ALTERNATE #1 #2: ALTERNATE #2 Numbe Description of Item Unit Cost* Unit erosion control as designs all disturbed areas seeded Quantity Item Cost Quantity Iltem Cost A EROSION CONTROL Native Seeding w/ 2 Tons of Straw Mulch (Crimped) $500.00 AC 15 $7,500.00 18 $9,000.00 Sediment Fence Barrier $4.00 LF 450 $1,800.00 450 $1,800.00 Straw Bale Units (5 bales/unit) $55.00 EA 40 $2.200.00 $0.00 $11.500.00 $10,800.00 SUBTOTAL MULTIPLIER 1.5 1.5 $17.250.00 $16,200.00 TOTAL DEPOSIT TOTAL SECURITY REQ'D. $17,250.00 - unit costs are mstanec costs. APPENDIX C 1 1 1 1 FOSSIL CREEK DRAINAGE BASIN MASTER DRAINAGEWAY PLANNING STUDY FORT COLLINS, COLORADO Prepared for City of Fort Collins, Colorado Larimer County, Colorado Colorado Water Conservation Board BY Simons, Li & Associates, Inc. PO Box 1816 Fort Collins, Colorado 80522 Project Number CO-FC-01 August 1982 8.2.2 Alternative 2 ' Channelization and enlarged road crossings were considered under Alternative 2 as shown in Figure 30. Vegetated, trapezoidal channels with ' concrete trickle channels were designed to carry the 10-, 50- or 100-year developed flows. Alternatives 2a, 2b and 2c refer to the 10-1 50- and ' 100-year channel design frequencies, respectively. Manning's equation, assuming uniform flow, was used to size the channels. Design flow depths were limited to four feet, channel velocities were limited ' to 7.5 ft/sec, side slopes ranged from 4h:1v to 5h:1v, and Manning's roughness coefficient was equal to 0.035. For the design channel, one foot of freeboard ' was allowed and a 10 foot access road for maintenance was included in the .top width Right-of-way (ROW) requirement. ' Table 27 presents a summary of the channel design data for Alternatives 2a (10-year), 2b (50-year) and 2c (100-year) along Fossil Creek. ' Enlarged crossings are required at nine locations along Fossil Creek:_._:' _ The dimensions of the box culverts and spans are listed in Table 28 for,...,,,.... 1 Alternatives 2a (10-year), 2b (50-year) and 2c (100-year). Velocities along the channels downstream of Highway 287 were less than five ft/sec, which will limit erosion along the channel. Velocities along the ' channels upstream of Highway 287 were between 6 and 7.5 ft/sec. Enlarged openings at channel crossings along the tributaries.were assumed ' when computing design flows for Fossil Creek.. ' 8.2.3 Alternative 3 Alternative.3 utilized the natural storage behind road embankments, ' Figure 31. Where necessary to prevent overtopping the road during the 100-year recurrence interval flood for developed conditions, the culverts at ' the channel crossing were enlarged. Development would not be allowed in the flood plain. A vegetated trapezoidal channel between Fossil Creek Reservoir... and Union Pacific Railroad is recommended because of the limited storage ' upstream of County Road 11. Enlarged channel crossings along Fossil Creek are required at County Road 11, Trilby Road (County Road 34), Lemay Avenue (County Road 13) and Shields Street. Improvements along the tributaries were sized for Stanton Creek at County Road 32 and Lemay Avenue (County Road 13) and Lang Gulch at Trilby Road (County Road 34) and Shields Street. These improvements were not considered in the economic analysis. ' 56 �' '\ Bur '•.\ ....\.. Tiibu/oiy �...—...� �...` •� � 3� •'\ - \...\ �•..�.. \— _... \ •\•••� "•` . -_ _ Fossil Creek ..i\ •• /. � .\ Pei .•\ '� \ � .__. .�, \• _ �•. �...� 40 0 to. _ \...� \ ^•..J / reservoir Ir — SMilh Creek �..._.:-�.../-. ;) :l i _ Y 0 c co o 0 D Cou y Road 34 (Trilby Rood) 00 lol d E m c / P •••\ Fossil Creek Reservoir \ :....:. ..i ofp moo a m � \ G Ici o v a \p% / \ o 1 0 / Duck .) County Road 32 Loke 1 •i ( I I FOSSIL CREEK MASTER DRAINAGEWAY LEGEND PLANNING STUDY CITY OF FORT COLLINS \LLLLV RAISE ROAD /fT1T1\ SCHEMATIC OF HIM COLORADO.WATER CONSERVATION BOARD LARIMER COUNTY, COLORADO RIPRAP tam PROPOSED IMPROVEMENTS GRASSLINED CHANNEL SCALE ALTERNATIVE 3 �I & INC. APRIL, 1982 1000 O 2000 IMPROVED CROSSING SWONS, ASSOCIATES, ENLASTENLARGED CULVERTS feet ED DETENTION FORT COINS, CO�ORAdO v 59 FIGUKt 01 1� Additional construction requirements included riprap downstream of chan- nel crossings, a headwall to reduce entrance losses at the Union Pacific 1 Railroad crossing, bank protection along Fossil Creek near Portner Reservoir, 1� stabilization of the southwest wingwall at the C&S Railroad crossing on Fossil Creek, and protection of the downstream embankment at Fossil Creek Drive and Fossil Creek. Table 29 presents a summary of the design data for Alternative 3. The {{ table includes design storage volumes, surface area, outlet capacity and 11 outlet dimensions. .J IJ8.2.4 Alternative 4 Alternative 4 (Figure 32) considers raising road embankments in order to 1 maintain three feet of freeboard at channel crossings and preventing develop- ment within the 100-year flood plain during the 100-year recurrence interval. -flood for developed conditions. Alternative 4 also includes channeliiation LJ from the Union Pacific Railroad to Fossil Creek Reservoir due to the -limited 1 storage behind County Road 11. 1 Embankments were raised along Fossil Creek at County Road 11, Trilby Road J (County Road 34), Lemay Avenue (County Road 13) and Shields Street. To evalu- ate this alternative, embankments were raised along Stanton Creek at County Road 32 and Lemay Avenue (County Road 13) and along Lang Gulch at Trilby Road 1� (County Road 34) and Shields Street. The design data for these improvements are presented 'in Table 30. 1 other -necessary improvements include riprap downstream of channel cross- .sings, a headwall, to reduce entrance lossee at the Union Pacific Railroad 1 crossing, bank protection along Fossil Creek near Portner Reservoir, stabili- zation of the southwest wingwall at the C&S Railroad crossing on Fossil Creek and protection of the downstream embankment at Fossil. -Creek Drive and Fossil 1 1 Creek. ' Table 29. Alternative 3, Design Data for Sizing Detention Ponds and Outlets. ' Location ' Fossil Creek ' Reach 1, County Road 11 Reach 2, Union Pacific ' Railroad and Trilby Road (County Road 34) Reach 21 County Road 13 ' (Lemay Ave) Reach 5, Shields Street ' Stanton Creek - Reach 6, County Road 32 Reach 6, County Road 13 (Lemay Ave) ' Lang Gulch ' Reach 7, County Road 34 (Trilby Road) ' Reach 7, Shields Street 1 ' 60 Storage Oulet Proposed Volume Capacity Outlet (ac-f t) (cfs) Dimension Surface Area (acres) 30 1,300 2-6'x10' box 10 600 1,380Existing 25 1,550 2-6'x12' box 60 19.5 3,200 ,10'x32' span 4 9 500 1-6'x10' box 2 13.6 880 2-41x12' box 3 26 780 2-4'x10' box 5 3 400 1-41x10' box 1 44 570 -1-6'x10' box 11 u 1 1 1 1 1 1 FINAL DRAINAGE REPORT FOR PROVINCETOWNE/PORTNER S.I.D. CITY OF FORT COLLINS COUNTY OF LARINER STATE OF COLORADO DECEMBER, 1984 Prepared by: Parsons S< Associates Consulting Engineers 432 Link Lane Plaza Fort Collins$ Colorado 80524 Project Number 84.08 S.I.D. I 1 1 0 1 1 1 1 t 1 1 proposed land uses will occur including: a variety of Residential Development in the low to medium density range, Commercial/Retail uses, Business Services, Industrial/Tech Park, City Parks, and scenic stormwater- detention facilities. HYDROLOGIC ANALYSIS The Rational Method and the Colorado Urban Hydrograph Method have been utilized to calculate stormwater runoff flows for the 2-7 10-7 and 100-year developed return period storms for the various tracts in Provincetowne/Portner. The Drainage Map identifies the basin boundaries, design points, and summarizes the results of the hydrologic analysis of these sub -basins. In addition, offsite stormwater contributes runoff to the Robert Benson Detention Lake and was considered to release at a controlled rate into the development. It should be noted at this point that the calculated flows in Provincetowne/Portner are approximate since details of the interior drainage patterns, street layouts, and building locations within individual tracts have not been permanently/ established. However, this report is based upon the best data avaiilable at this -time. It i.s the intent of the developer to maintain the flow patterns and .-basin configurations presented herein as much as possible. Where changes are made in future projects, detailed drainage studies will be made and appropriate revisions to this report will be recommended. HYDRAULIC ANALYSIS Once the runoff volumes from the site were estimated, various combinations of flows were used to size the storm sewer system to be built as part of this S.I.D. That runoff which does not enter this system from street inlets is captured by an array of temporary swales and conveyed to the storm sewers. The inlets included in this design are only as numerous as necessary for this intermediate development.... -As -further tracts develop, -the-storm se'wier 'system will be extended and additional inlets will be designed as required. As the storm sewer system expands, the temporary swales will be eliminated. In addition to storm sewer and swale sizing, street inundations due to the -major storms were computed. It was -found that if on -site detention is provided on developed tracts within Provincetowne/Portner then street inundation can be kept within the limits of City design criteria at all design points. DETENTION No detention facilities are included in this S.I.D. excepting the transient storage provided in the temporary drainage swales during ' major storm events. However, complete detention is assumed to exist and to be maintained within Robert Benson Lake for its entire basin ' both now and after its dam relocation. Design flows herein have assumed no greater than minor storm release under all circumstances. Furthermore, this report assumes that on —site detention will be ' provided as tracts are developed throughout the Pr-ovincetowne/Por-tner project and the drainage facilities included in this S.I.D. hzwe•bee'n sized accordingly. 1 7 hn D. Me.tqChl! n 1 of ey Wynne, P.E. #144b1 14961 ON At. 1 1 1 : 1 1 1 ' \• 1 I� \ '.. L: ,`•� :..Y' \ P.��.' .`.a a % `���:: ;. �_ ij_ ! I� '•`•. � lS..� oa..i; ,i'\i. \.\ � � i of I •) `•\ •�\,� ;. _ - I I __ :='ri•-'•-+_- '.7.+•.-' - - - .Nt . _ - .T'�;R.Pi :: /.�4 � I L.1 ,�' -1 +� 'Lt I. I I �_ '�1 -, a !•� lb °pl °� �� .�P�°�._�'�°�'� � ° �PD°rho) D°�'Q°9°U°D'�4Q°gyp •, \ � � ,' +'� .__ _ �,: ; ��. '�� �,^ \ � \ ,`: Ddldl dl � 0�I � �lDa7dl s� dl� dl �l I _ _, %� � �•.\ _0� Ir - n '� a 6� \J 1,♦.\ \ 1•i I\ Cam♦ .7f ...���(f�-\` ` • I 'i` 1 _`` 1'�,�,-i i\\\�i '•� t/'♦\Y. �i�`.\\\\\\ �7I_ __ ~ i\ ♦'\ ♦ `' % .'ice `.\ \� �' -.,/ - , 71 7. 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'\ 'i •r• n. \` 7 O `1 rim / \\\`• \ � � T I ` I 0 HORIZONTAL CONTROL O VERTICAL CONTROL ��--yy 7 1 - •0 1 h -�- ••� - • SPOT ELEVATION C U - '. ♦ 4A v ' '� - - ``r4260f.:INDEX CONTOUR INTERMEDIATE CONTOUR DEPRESSION FENCE i •' \ .I „ ""•'-'•'-` GUARD RAIL . • \ '-•.� = DIRT ROAD I I • � ' PAVED ROAD RAILROAD r STREAM DITCH 1 - ; ) C CULVERT HEADWALL A- d BUILDING ,,...__,.. ........: '� � TREE' OUTLINE I6 JI h PONER-TELE, POLE JJ� r•./i I LY •IQ - OA STORM SEWER LINE Q DESIGN POINT / - / �r i,� : - •03 •• • jNLET DESIGN POINT gas nun mm®m man© aces WOno 90�g11pm�maumn can noun onmmmmann A000Q0%non � . 0=2 00 mmmmm000o, m®m©mmume nnnnnnnnn guano nun 11 11 11 11 11 I� IL IL 1 1 1 II FLOW PATTERN SCHEMATIC DIAGRAM Legend: Hydraulic Design Point/Local Drainage Basin Drainage Structure Target Local Acreage / Accumulated Acreage Location N.A. = Not Applicable V:E. = Victoria Estates SOUTH BASIN Bristol Rd 22/E-2 Windsor Rd Stanton rl/E-1 8.08/N.A. 5.17/13.25 Creek MIDDLE BASIN 25/A-1 U.S. 287 21/A-2 Benson Dam 190.26/N.A. 138.74/329.00 (Controlled Release) " 24/VE. Prop. Line 1/B-1 Bristol Rk 20/B72 A 44.0/N.A. 7 .6/429.44 5.10/484.5 Q Lemay Rd Unnamed Tributary to Stanton Creek NORTH BASIN 4/C-3 Province Dr 20.23/N.A. 2/C-1 Province Dr 3/C-2 Brittany. Or 8/C-4 Rimed a Line 5/D-3 13.28/N.A. 5.31/56.81 10.43/87.47' 11.09/102.88 19/D-2. Britian Rd -. a7/D-1 - rittany Rd 18.30/N.A. 4.32/N.A. ©Granville Or 6/D-4 Lemay Rd Drainage Along 34.19/155.37 Trilby Rd II ' CORRESPONDENCE LIST ' DESIGN POINT BASIN INLET SEWER LINE STREET / DESCRIPTION 1, 1.1 - 1.4 B-1 1,2,18,19 A, A-1 Bristol Drive 2, 2.1 C-1 3 C Province Rd, manhole for future connect. 3, 3.1-3.3 C-2 4,16,17 D, D-1 Brittany Drive 4, 4.1, 4.2 C-3 5, 6 E Province Road ' 5, 5.15 5.2 D-3 91 10 G Granville Drive 6 D-4 Future Lemay Avenue ' 7.1, 7.22 7..3 D-1 72 8. F, F-1 Granville Drive, Brittany Drive ' 8.1, 8.2 G-1 16A,16B L Rumford Place 9, 9.1, 9.2 D-2 14, 15 J Brittany Drive 10, 10.1-10.3 0-2 11,12,13 H, I Brittany" -Drive 11 E-1 M Bristol Drive 12 D-2 channel E. Summer Drive ' 13 G-1 exist. --K Trilby Road 14 ' 15 16 R.Benson B Bristol Drive, Irrigation ditch ' 17 ' 18 C-4 swale Control section for Lemay swale 19 20 B-2 Future Lemay Avenue 21 A-2 R. Benson Lake control structure ' 22 E-2 Future Windsor Road ' 23 E-3 exist. culvert Windsor Road, South Victoria Estates 24 V.E. none ' 25 A-1 exist U.S. 287, Del Webb development culvert, inlets ' DESIGN POINT ' SOUTH BASIN 11 ' 22 MIDDLE BASIN ' 25 21 ' 24 1 20 10 ' NORTH BASIN ' 2 4 7 18 5 9 ' 6 DESIGN POINT DESIGN FLOW RETURN EVENT DESIGN FLOW STRUCTURE FLOW (YR) (CFS). REMARKS 2 6.1 storm sewer 10 74.4 culvert Flow=120%xcumulative 100-yr 2 34.7 storm sewer. Historic release,D.Webb Dev. _< 2 < 34.5 Dam Outlet Struct. Controlled release 100 132.0 None Offsite drainage V.E. 10 110.9 Storm sewer Flow=10yr cumulative +_ R.Benson release 2 27.3 Storm sewer Historic release Middle Basin N/A 435 Irrigation Downstream pond elev. maintenance t 2 5.9 storm sewer 2 26.4 storm sewer Flow=cumulative 2 yr 10 72.2 storm sewer 100 13.8 storm sewer 100 240.1 swale Flow=cumulative 100 yr 2 61.5 storm sewer Flow=cumulative 2 yr. 2 14.9 storm sewer 2 20.4 storm sewer Historic release, North Basin ' FORMULAE Time of Concentration: 1.87(1.1 - Ccf)D'S Where: C = Runoff.Coefficient T = c D = Distance in feet S.33 S = Slope in percent ' cf =.Antecedent precipitation factor 1.0 for 2-year and 10-year 1.25 for 100-year. '. ' Velocity and Capacity: ' 1.487 X R'67 X so Where: n.='Manning's roughness coefficient V = n A = Cross -sectional area in square feet 1.n86 X S'S R = Hydraulic radius Q = X A X R'67 S = Slope in feet per foot ' ' Runoff Quantities: Q = CIAcf Where: C, = I = Runoff Coefficient Rainfall intensity, inches -per hour ' A = Area in acres cf = Antecedent precipitation factor 1.0 for 2-year and 10-year ' 1.25 for 100-year ' Runoff Volume: V = Q X Tc X 60 Where: Q = Runoff ,in cubic feet per second. Tc = Time of concentration ' Orifice Plate: Q = 0.65A v2g Where:. A =:Cross-section area in square feet ' g = Acceleration due to gravity, 32 feet/sec.'. h =.Height of water above center ' of opening ' Detention: Volume is computed by means of a program, using the Modified Rational Method which Varies the rate of flow in, while dis- charging ata constant rate. 1 ' HYDROLOGY CALCULATIONS SOUTH BASIN Design Point 11, Basin E-1 Area = 8.08 Ac. Length = 1150 Ft. Height = 27 Ft. Slope = 2.35% C = 0.20 Undevel,o,ped ' 2-YR 10-YR 100-YR ' Tc = 42.9 min. Tc = 42.9 Tc = 40.5 I = 1.15 in/hr I = 2:05 I = 3.40 Q = 1.9 cfs Q = 3.3 Q = 6.9 1 C = 0.50 Developed Tc = 28.6 Tc = 28.6 Tc = 22.7 ' I = 1.50 I = 2.65 I = 4.85 Q =,64 Q =10.7 :.. Q =29.4 ' Design Point 22, Basin E-2 ' Area = 5.17 Ac. Length = 750 Ft. Height = 16 Ft. Slope = 2.13% C = 0.20 Undeveloped 2-YR 10-YR 100-YR Tc = 35.8 min. Tc = 35.8 Tc = 33.8 ' I = 1.3 in/hr I = 2.3 I = 3.85 Q = 1.3.cfs Q = 2.4 Q = 5.0 ' C = 0.85 Developed Tc = 10.0 Tc = 10.0 Tc = 4.0 ' I. = 2.50 I = 4.40 I = 9.50 Q = 11.0 Q = 19.3 Q = 52.2 ' Cumulative: Basins E-1, E-2 Area = 13.25.Ac. Length = 1400 Ft. Height = 33 Ft. Slope = 2.36% ' C = 0.20 Undeveloped ' 2-YR 10-YR 100-YR Tc = 47.30 Tc = 47.30 Tc = 44.7 I = 1.08 in/hr I = 1.63 I = 3.23 ' Q = 2.9 cfs Q = 4.3 Q = 10.7 r ' HYDROLOGY CALCULATIONS - 2 Cumulative: Basins E-1, E-2 (Continued) C = 0.64 Composite Developed ' 2-YR 10-YR 100-YR Tc = 24.2 Tc = 24.2 Tc = 15.8 ' I = 1.65 I = 2.90 I = 5.85 Q = 14.0 Q = 24.6 Q = 62.0 MIDDLE BASIN Design Point 25, Basin A-1 ' Area = 190.26 Ac. Length = 3500 Ft. Height = 100 Ft. Slope = 2.86% C 0.22 Composite Undeveloped ' 2-YR 10-YR 100-YR Tc = 68.6 min. Tc = 68.6 -..,:''T... = 64.2 . I = 0.83 in/hr I = 1.46 I = 2.45 Q . = 34.7 cfs Q = 61.1 Q - = 128.2 ' C = 0.58 Estimated Composite Developed (Webb Master Plan 9/5/84) Tc = 40.53 Tc = 40.53 Tc = 29.23 ' I = 1.20 I = 2.15 I = 4.22 Q = 132.4 Q = 237.3 Q = 582.1 ' Design Point 21, Basin A-2 ' Area = 138.74 Ac. Length = 1700 Ft. Height = 46 Ft. Slope = 2.70% _ C=..0.23 Composite Undeveloped-- - ' 2-YR 10-YR 100-YR Tc = 48.2 min.' Tc = 48.2 Tc = 45.0 ' I = 1.08 in/hr I = 1.90 I._ =w3.25 Q = 34.5 cfs Q = 60.6 Q = 129.6 ' C = 0.44 Composite Developed Tc = 36.5 Tc = 36.4 Tc = 30.5 I = 1.30 I = 2.30 I = 4.13 ' Q = 79.4 Q = 140.4 Q = 315.1 1 1 HYDROLOGY CALCULATIONS - 3 Design Point 24, Basin V.E. Area = 44.0 Ac. Length = 2200 Ft. Height = 53 Ft. C = 0.45 Current Development 2-YR 10-YR Tc = 42.5 min.• Tc = 42.5 Tc = 35.2 I = 1.20 in/hr I = 2.10 I = 3.75 Q = 23.8 cfs Q = 41.6 Q = 92.8 C = 0.50 Future Development Tc = 39.3 Tc = 39.3 Tc I = 1.22 I = 2.20 I Q. = 26.8 Q = 48.4 Q Design Point 1, Basin B-1 Area = 49.6 Ac Length = 1500.Ft. C = 0.20 Undeveloped 2-YR 10-YR Tc = 50.9 min. I = 1.03 in/hr Q = 10.1 cfs Height =-32 Ft. Tc = 50.9 I = 1.83 Q = 18.0 C = 0.45 Composite Developed Tc = 36.8 Tc = 36.8 I = 1.28 I = 2.28 Q =..28.6 Q . = 50.9 Design Point 20, Basin B-2 Area = 55.10 Ac. Length = 1400 Ft. C = 0.20 Undeveloped 2-YR 10-YR Tc = 54.4 min. I = 1.00 in/hr Q = 11.0 cfs Tc = 12.5 I = 2.30 Q = 101.9 Tc = 54.4 I = 2.70 Q = 29.8 C = 0.85 Developed Tc = 12.5 I = 3.30 Q = 146.1 Slope = 2.41% 100-YR = 31.1 = 4.08 = 132.0 Slope = 2.10% 100-YR Tc = 48.1 I = 3.09 Q = 38.0 Tc = 30.4 I = 4.13 Q = 115.2 Height = 38 Ft. Slope = 2.71% 100-YR Tc = 51.4 I 2.90 Q = 39.9 Tc = 5.0 I = 9.00 Q = 498.2 C HYDROLOGY CALCULATIONS - 4 Cumulative: Basins A-1, A-2 Area = 329.00 Ac. Length ='6500 Ft.. Height = 107 Ft. Slope = 107(0.8*6500)=2.06% Peak Flow, Undeveloped Condition CUHP with Impervious Area = 34% estimated 2-YR 10-YR 100-YR Qp = 82.6 cfs. QP = 326.2 Qp = 640 Vol = 7.4 Ac-Ft Vol = 24.2 Vol = 46.3 Peak Flow, Developed CUHP with Impervious Area = 50% estimated 2-YR 10-YR 100-YR Qp = 196.8 cfs Qp = 370.4 Qp = 687.0 Vol = 20.5 Ac-Ft Vol = 28.1 Vol = 51.2 Cumulative: Basins B-1, V.E. Area = 93.6 Ac. Length = 3400 Ft. Height 60 Ft. C = 0.32 Composite, Undeveloped 2-YR 10-YR Slope = 1.76% 100-YR Tc = 70.4 min. Tc = 70.4 Tc = 63.2 I = 0.82 in/hr. I = 1.43 I = 2.49 Q- = 24.6 Q = 42.8 Q = 93.2 C = 0.48 Composite Developed Tc = 56.0 Tc = 56.0 Tc = 45.2 I = 0.96 I =.1.70 I = 3.23 Q = 43.1 Q = 76.4 Q 181.4 Cumulative:.Basins B-1, B-2,, V.E. Area = 148.7 Ac. Length = 4900 Ft. Height = 85 Ft. Slope = 1.73% C = 0.27 Composite Undeveloped 2-YR 10-YR 100-YR Tc = 90.5 Tc = 90.5 Tc = 83.1 I = 0.68 I = 1.19 I = 1.98 Q = 27.3 Q = 47.8 Q = 228 C = 0.62 Composite Developed Tc = 52.3 Tc = 52.3 Tc = 35.4 I = 1.00 I = 1.78 I = 3.76 Q = 40.1 Q = 71.5 Q = 433.3 i ' HYDROLOGY CALCULATIONS - 5 NORTH BASIN ' Design 'C-1 Point 2, Basin ' Area = 13.28 Ac. Length = 1000 Ft. Height = 18 Ft. Slope = 1.80% C = 6.20 Undeveloped ' 2-YR 10-YR 100-YR Tc = 43.8 min. Tc = 43.8 T = 41.3 ' I = 1.15 in/hr I = 2.00 Ic = 3.40 Q = 2.8 cfs Q = 4.8 Q = 10.2 ' C = 0.34 Composite Developed Tc = 36.9 Tc = 36.9 Tc = 32.8 ' I = 1.30 I = 2.30 I = 3.95 Q = 5.9 Q = 10.4 Q = 22.3 Design Point 3, Basin C-2 Area = 45.31 Ac. Length = 2800 Ft. Height = 53 Ft. Slope = 1.89% ' C = 0.20 Undeveloped ' 2-YR 10-YR. 100-Yr Tc = 72.0 min. Tc = 72.0 T = 68.0 ' I Q = 0.80 in/hr = 7.2 cfs I = 1.40 c I = Q = 12.5 Q = 12.40 2.0 ' Tc C = 0.48 Composite Developed = 49.6 _Tc 49.6 Tc = 40.0 I Q = 1.05 = 22.8 I = 1.87 I = 3.50 ' Q = 40.7 Q = 95.2 Design Point 4, Basin C-3 ' Area = 20.23 Length = 1100 Ft. Height = 26 Ft. Slope = 2.36% ' C = 0.20 Undeveloped 2-YR 10-YR 100-YR ' Tc = 41.9 min. Tc = 41.9 Tc = 39.6 I = 1.20 in/hr I = 2.10 I = 1.25 ' Q = 4.9 cfs Q = 8.5 Q = 17.7 C = 0.85 Developed ' Tc = 11.6 Tc = 11.6 Tc = 4.7 I = 2.40 i = a.pn r - 0 In ' HYDROLOGY CALCULATIONS - 6 Design Point 18, Basin C-4..' ' Area = 10.43 Ac. Length = 950 Ft. Height = 17 Ft. ' C = 0.20 Undeveloped 2-YR 10-YR ' Tc = 42.7 min. Tc = 42.7 I = 1.15 in/hr I = 2.05 ' Q = 2.4 cfs Q = 4.3 . C = 0.76 Composite Developed Tc = 16.1 Tc = 16.1 ' I = 2.05 I = 3.60 Q = 16.2 Q = 28.5. ' Design Point 7, Basin D-1 ' Area = 4.32 Ac. Length = 850 Ft: C = 0.20 Undeveloped ' 2-YR 10-YR Tc = 37.5 min. Tc = 37.5 ' I = 1.30 in/hr I = 2.25 Q = 1.1 cfs Q = 1.9 C = 0.5 Developed Tc = 25.0 Tc = 25.0 ' I = 1.60 I = 2.85 Q = 3.50 Q = 6,20 Design Point 5 Basin D-3 Slope = 1.79% 100-YR Tc = 40.3 I = 3.45 Q = 9.0 Tc I Q Height = 19 Ft. = 7.1 = 8.1 = 80.2. Slope = 2.24% 100-YR Tc = 35.4 I = 3.75 Q = 4.1 Tc Q Area = 11.09 Ac Length = 1100 Ft. Height = 34 Ft. = 19.8 = 5.10 = J3.0 Slope = 3.09% ' C = 0.20 Undeveloped 2-YR 10-YR 100-YR Tc = 38.3 min. Tc = 38.3 Tc = 36.2 I = 1.30 in/hr I = 2.20 I = 3.70 ' Q = 2.9 cfs Q = 4.9 Q • = 10:3 C = 0.49 Composite Developed Tc = 26.0 Tc = 26.0 Tc = 20.8 I = 1.60 I = 2.80 I = 5.10 ' 0 = 8.7 Q = 15.2 Q = 34.6 1 ' HYDROLOGY CALCULATIONS - 7 Design Point 9, Basin D-2 ' Area = 18.30 Ac Length = 1700 Ft. C = 0.20 Undeveloped ' 2-YR 10-YR ' Tc = 49.1 min . - I = 1.05 in/hr Q = 3.8 cfs 1 Tc = 49.1 I = 1.85 Q = 6.8 C = 0.55 Developed Height = 48 Ft. Slope = 2.82% 100-YR T = 46.4 c I = 3.10 Q = 14.2 Tc = 30.0 Tc = 30.0 Tc = 22.5 11 ' I = 1.48 I = 2.60 I = 4.87 Q = 14.9 Q = 26..2 Q = 61.3 ' Design Point 6, Basin D-4 _. ',"Area = 34.19 Ac. Length = 1800 Ft. Height = W.,Ft:. Slope = 3.67% C = 0.20 Undeveloped ' 2-YR 10-YR 100-YR T = 46.3 min. c ' I = 1.10 in/hr Q = 7.5 cfs 1 T = c 46.3 I = 1.95 Q = 13.3 C = 0.55 Developed Tc = 28.3 Tc = 28.3 I = 1.50 I = 2..67 ' Q = 28.2 Q = 50.2 ' Cumulative: Basins C-1, C-2 Area = 58.61 Ac. Length = 2800 Ft. C = 0.20 Undeveloped 2-YR 10-YR ' Tc I Q ' Tc I :1 Q T = 43.7 c I = 3.25 Q = 27.8 Tc Q Height = 53 Ft. = 72.0 min. Tc = 72.0 = 0.80 in/hr I = 1.40 = 9.4 cfs Q = 16.4 C = 0.45 Composite Developed = 52.0 Tc = 52.0 = 1.00 I = 1.80 = 26.4 Q = 47.5 = 21.2 = 5.05 = 118.7 Slope = 1.89% 100-YR Tc = 68.0 I = 2.40 Q = 35.2 Tc = 43.0 I = 3.33 Q = 109.8 HYDROLOGY CALCULATIONS - 8 Cumulative: Basins C-1, C-2; C-3, C-4 ' Ft. Slope = 1.85% Area = 89.25 Ac. Length_.= 4000 Ft. Height = 74 ' C = 0.20 Undeveloped 2-YR 10-YR 100-YR ' Tc = 86.7 min. Tc = 86.7 Tc = 81.9 I = 0.70 in/hr I = 1.21 I = 2.01 ' Q = 12.5 cfs Q = 21.6 Q = 44.8 C = 0.58 Composite Developed ' Tc = 50.1 Tc = 50.1 Tc = 36.1 I = 1.04 I = 1.75 I = 3.71 Q = 53.8 Q = 90.6 Q = 240.1 ' Cumulative: Basins C-1, C-2, C-3, C-4, D-1, D-3 ' Area = 104.66 Ac. Length = 4055. Ft. Height 90 Ft.. Slope = 2.22% C = 0.20 Undeveloped 2-YR 10-YR 100-YR Tc = 82.2 min. Tc = 82.2 Tc. = 77.6 I = 0.72 in/hr I = 1.28 I = 2.10 Q = 15.1 cfs Q = 26.8 Q = 54.9 ' C = 0.56 Composite Developed Tc = 49.3 Tc = 49.3 Tc = 36.5 tI = 1.05 I = 1.89 I = 3.71 Q = 61.5 Q = 110.8 Q = 27.1.8 ' Cumulative: Basins C-1, C-2, C-3, C-41 D-1; D-2, D-3, D-4 Area = 157.15.Ac. Length = 5405.Ft. Height .= 120 Ft. Slope = 2.22% C = 0.20 Undeveloped ' 2-YR 10-YR 100-YR Tc = 94.8 min. Tc = 94.8 Tc. = 89.6 I = 0.65 in/hr I = 1.13 I = 1.87 ' Q = 20.4 cfs Q = 35.5 Q = 73.5 C = 0.56 Composite Developed. ' Tc = 56.9 Tc= 56.9 Tc = 42.2 - I = 0.94 I = 1.69 I - 3.38 ' Q = 82.7 Q = 148.7 Q = 371.8 FINAL DRAINAGE REPORT FOR SOUTH LEMAY SPECIAL IMPROVEMENT DISTRICT #86 JULY 1985 PROJECT NO.: 407.1 Prepared for: MSP Companies/Dueck Companies 650 South Cherry St., Suite 1050 Denver, Colorado 80222 (303) 399-9804 Prepared by: Engineering Professionals, Inc. 2625 Redwing Rd., Suite 110 Fort Collins, CO 80526 (303) 226-3852 Runoff concentrated in the Lagoon Tributary will be passed under Lemay by. five (5) 6-foot span by 3-foot rise precast concrete box culverts at Lemay station 75+00. These box culverts were sized assuming a 100-year discharge of 680 cfs as recommended by Tom Gathmann of the City of Fort Collins Storm Drainage staff, based on Storm Water Management Model modeling by Simons, Li and Associates. Refer to the attached record of F communication dated April 3, 1985. �. Runoff concentrating at the' southwest corner of the Trilby Road and Lemay.Avenue intersection corresponding approximately to Lemay station 62+15 will be. routed through culverts under Lemay and allowed to discharge into the swale along the south side of Trilby Road. The runoff will flow in the swale east to Fossil Creek. Culverts were sized to accomodate the 100-year historic discharge of 73.5 cfs, taken from the approved "Final Drainage Report for Provincetowne/Portner SID," December, 1984, by Parsons and Associates. Runoff concentrating in a tributary of Stanton C•reek'.:;. corresponding to Lemay station-15+60 will be routed under Lemay ..::.. via a multiple barrel culvert installation and discharged into Stanton Creek. Sufficient culvert capacity has been provided to accomodate the 100-year historic discharge of 228 cfs, as calculated in ,.the approved "Final Drainage Report for Provincetowne/Portner SID," December, 1984, by Parsons and Associates. Grass -lined open channels will be constructed along portions of the project immediately west of the west Lemay right-of-way line. These open channels will' intercept runoff which, if allowed to sheet flow into Lemay Avenue, would result .in gutter flow rates greater than allowable under City of Fort Collins criteria. 'These channels'are intended to be temporary, to be replaced by permanent drainage systems as the land to the west of- Lemay Avenue develops. Unless otherwise noted, design flow rates i were computed using the rational method. The channels were sized for 1.33 times the computed rational method peak discharge using Manning's Equation and the average slope over the reach of the channel. Channel capacity and velocity were checked at points of maximum and minimum slope. Detailed calculations are attached. The following describe the locations of the proposed open channels and summarize the design calculations. The approved construction drawings for the Provincetowne/Portner SID contain plans for an open channel extending from Province Road north to the Lemay Avenue -Trilby Road intersection. This channel will be constructed per the Provincetowne/Portner plans, sheets 14/16 and 15/16. This channel design is also included in the South Lemay SID construction drawings on sheet 17/31. An open channel will also be constructed from Trilby Road north to the Lagoon Tributary. The 27.4 acre basin contributing to this channel is denoted as Basin VA and is delineated on the attached drainage schematic. The 100-year historic flow contributing to the channel was calculated as 22.6 cfs; the channel was sized to accomodate a flow of 30.1 cfs. The reader will note that the channel flo-w velocity during the major storm is less than 2 feet per second; .we do not feel that this presents any problems, as the. land within the basin tributary to the _..channel is relatively well -vegetated and should not produce much sediment. Detailed hydrologic and hydraulic calculations used in the design of this channel may be found in the appendix. Open channels were also considered from Larimer County Road 32 north to the Stanton Creek Tributary (Basin IA on the attached schematic), from the high point at Lemay station 29+40.70 south to the Stanton Creek Tributary (Basin IB), and.from the high point at station 29+40.70 north to Province Road (Basin IIA). Calculations showed these channels to be unnecessary, as the street and storm sewer as designed have adequate capacity to accomodate the historic 2-year and 100-year runoff from the areas directly tributary to the street As"the land to'the'Vest of South Lemay, develops, developed runoff wili not be allowed to. enter the street right-of-way, but will be directed to detention areas via a drainage system located outside of the Lemay right- of-way, per the approved "Final Drainage Report for Provincetowne/Portner SID," December, 1984, by Parsons and Associates. Offsite basins contributing to these portions of Lemay Avenue are delineated on the attached drainage schematic. Runoff calculations, a street capacity analysis, and an inlet capacity analysis are included for each area in the attached calculations. Inlet and storm sewer facilities intended to drain the area within the Lemay Avenue right-of-way were sized using the fational method. A runoff coefficient of 0.73 based on the typical ultimate cross-section was used. Times of concentration were calculated using the velocity calculated from Manning's equation as modified for triangular channels, the average longitudinal gutter slope, and an assumed depth of flow of 6 _ inches. The City of Fort Collins Rainfall Frequency -In tens ity- Duration curve was used to obtain the 2-year, 10-year, and 100- year rainfall intensities, appropriate to the zoning of adjacent i �.. lands. With the exception of the areas mentioned in,the preceding paragraph, and a portion of Trilby Road, the only area assumed to contribute to gutter flow in Lemay was the'area witin the Lemay right-of-way. Peak discharges from Trilby Road were calculated using the. rational method with slopes and areas based i on preliminary plans for Trilby Road prepared by Parsons and Associates. Nomographs used for inlet and culvert sizing are included. Where feasible, we intend to use concrete sidewalk culverts in place of Type R inlets; refer to the construction drawings for proposed locations of sidewalk culverts. Refer to the attached drainage and inlet sizing calculations for further information. Street capacities for the minor event were checked using Manning's equation as modified for triangular channels, allowable depth of flow at the flow line of 0.47 feet, and the reduction factor as -called for by City criteria. Major street capacities were checked using the standard Manning's equation, an "n" value of 0.020,.an applicable reduction factor as called for by City criteria, and an allowable depth of flow of 0.78 feet at the flow line. This maximum flowline depth assumes all flows to be contained within the street right-of-way. City criteria would allow an additional 0.45 feet of flow depth and a corresponding increase in major storm. street capacity. Calculations are .. attached. - The Lemay Avenue basin designated as Basin II on the attached schematic flows into an open channel and "eventually to the southwest corner of the Lemay-Trilby Road intersection. A i detention basin is proposed for this location in the future, per the approved "Final Drainage Report for Provincetowne/Fortner SID," December, 1984, by Parsons and Associates. We have i calculated the volume of runoff which Lemay Avenue will contribute to this detention area as approximately 0.4% of the total required, and conclude that the additional volume of runoff contributed by this portion of Lemay Avenue is insignificant.. Calculations are attached. The behavior of the storm drainage system for South Lemay has been analyzed for the major event. Some comments follow: The inlets and storm sewer at the sump in the vicinity of station 15+60 appear to have adequate capacity to carry the 100- year peak discharge at an assumed flowline depth of 0.78 feet. Should the inlets.become plugged, the water surface may rise an additinal 0.45 feet and still remain within City criteria for' allowable major storm street flow depth. As the waster surface rises, water will begin to overflow the east and west right-of- way lines into the Stanton Creek tributary. Although the inlets immediately south of Province Road in the vicinity of Lemay station 38+10 will be constructed to operate under sump conditions during the minor storm, it is difficult to predict the behavior of flows in this area during the major event. Street capacity is adequate for the major - event, as is inlet capacity (assuming sump conditions). The controlling factor will be the depth of flow in the open channel into which the storm sewer discharges. Should the depth of flow be less than 2 feet, the inlet/s'torm sewer system has. adequate capacity to pass the entire 100-year discharge. If the depth -of flow in the channel is 2 feet or areater, the inlets will surcharge and water will flow north on Lemay Avenue. The 2=foot depth referred to is apparently the maximum depth allowable within the channel, as taken from the approved Provincetowne/Portner drainage report. We expect the flow depth to reach t.he.maximum depth in the channel at the time of concentration for the tributary area to the west of Lemay Avenue. The 100-year historic time of concentration for this ..area is approximately 80 minutes - As the time -of- concentration of the Lemay Avenue basin is on the order of 5 minutes, the peak .� flow from the street should have passed through the system by the time the historic 100-year peak from the remainder of the basin �! to the west reaches this point. j The inlets immediately south of the Trilby-Lemay Avenue intersection are also designed to behave as sumps during the minor event, but the behavior of runoff during the 100-year event is difficult to predict. Assuming a flow depth of 0.78 feet at 1 the flowline, and sump behavior, the inlets and storm sewer have i enough capacity to handle all but 4.7 cfs of the 100-year flow. ! We anticipate that this. additional runoff will, in conjunction . with flows originating on Trilby Road west of Lemay, cause the i west half of Lemay Avenue north of the Trilby-Lemay intersection to be over capacity. We expect as much as 4 cfs of storm water to overflow the west right-of-way line and then flow into, the contour ditch leading to the Lagoon Tributary. We stress that, in using the ter m."over capacity," we are refering to the maximum flow which can be accomodated within the street right-of-way. Flow'depth can increase an additional 0.45 feet and still remain within the City criteria of 6" maximum depth at the face of the outfall curb and gutter at the median island; emergency vehicles should encounter no difficulties in traversing the street under these conditions. The additional runoff flowing past the Trilby- Lemay Intersection should not cause the east half of Lemay north of the Trilby-Lemay intersection to be over capacity, as the 100- year runoff generated by the east half Lemay right-of-way north of Trilby is approximately 5 cfs .below the maximum street capacity. Storm water may also flow, east from the Trilby-Lemay intersection onto the unimproved portion of the Trilby Road: If this occurs, runoff will flow into the borrow ditches on either side of Trilby and flow into Fossil Creek. The sump at Lemay station 74+75-will overflow both the east and west Lemay right-of-way lines. Assuming that the overflow past the right-of-way lines behaves as a free overfall, and assuming that water is ponded at the maximum depth of 0.5 feet at the face. of. the outf all curb and gutter at the median island as allowed by City criteria, approximately 78 cfs may overflow each right-of-way line. The calculated 100-year peak flow to the sump. is approximately 29 cfs, therefore, the depth of flow over the right-of-way should be minimal. Calculations are attached. The sump immediately south of Fossil Creek, station 107+35, _ will also overflow both the east and west right-of-way lines. t This sump has the same geometry as the sump at station 74+75; its overflow capacity is -approximately 78 cfs per side. The calculated .peak flow to this point is approximately 69 cfs; the depth of flow over the right-of-way should be minimal. Respectfully, ENGINEERING PROFESSIONALS, INC. I Jonathan B.Howard Michael N. Schmid, P.E.. JBH:psm 1■ - Basin III South Lemay Sta 38 +'09.65 to Sta 62 + 84.65 Area = 5.68 Acres L = 2475.00 Ft H = 48.79 Ft S = 1.97% V = 4.1 FPS Tc = 10 min. �2 = 2.5 IPH 1100 = 7.0 IPH C = .73 Q2 = (.73) (2.5) (5.68) = 10.37 cfs Q100 = (1.25)(.73)(7.0)(5.68) =,36.3 Minor Storm Allowable Gutter FLow = 10.82 CFS Minor. Storm,Streer Capacity. Adequate i Major Storm Allowable Capacity = 34.4 cfs .,See text of_ report. t , Basin IV Trilby Road, Parsons and Associates Sta 38+75 to Sta 52+77.90 A = 3.22 Acres L = 1402.90 H = 56.98 - 11.05 = 45.93 S = 3.27 % V = 4.5 FPS Tc = 5.2 min. ... 12 = 3.2 IPH 1100 =..7.0 IPH C = .82 42 = (.82) (3.2) (3.22) = 8.45 cfs 4100 (1.0.)(7.0)(3.22) = 22.5 cfs sta 15+59.65 East and west inlets each have inflow of 4.88 cfs. For sump conditions and assuming a 5' Type R inlet, theoretical capcity per foot of inlet length Q/L = 1.1 cfs/ft. Reduce Q/L by reduction factor of 0.80. Q/L = (1.1)(.80) = .88 cfs/ft L = 4.88/.88 5.5 ft Use a 10 foot inlet for both east and west inlets. Sta 38+09.65 Inflow to east and west inlets is 2.33 cfs For sump conditions and assuming a 5' inlet, Q/L = (1.1) (.80) _ .88 cfs. L=.2-.33/.88 = 2.65 ft Use a 5' inlet. Sta 62+25.34 Sump Conditions East inlet inflow = 5.19 cfs Assume 10' inlet: Q/L = (1.1)(.85) _ .94 cfs/ft L =5.5 ft Use a 10 foot inlet. .94 West inlet inflow = 5.19 + 4.2 (from south half of Trilby Road) = 9.39 cfs. Assume 10' inlet: Q/L = (1.1)(.85) = .94 cfs/ft L.=.. 9...39/9.4 = 10 feet Use a 10 foot inlet. Inlet Sizing cont'd Sta 63+47.32 Inlet on west.Lemay flowline, inflow from north half of Trilby = 4.2 cfs. Continuous grade conditions. Gutter Flowline Slope = 0.4% " From nomograph, inlet interception rate for 10 foot Type is .63 QINT = .63(4.2) = 2.65 cfs QBYPASS = 4.2 - 2.65 = 1.55 cfs Use 10 foot inlet. South Lemay Storm Sewer Sizing r Sta 38+06.48 o r, Q2 = 4.66 Q100 - 12. Culvert #2 Try 15" RCP ,,,Q2 = 3.33 Q100 = 6.35 Inlet Control HW/D2 = 1.1 HW = 1.38 Ft OR, Use 15" RCP HW/D100 = 4.2 HW = 5.25 Ft. See Comments in Text of Report. Outlet Control WS elevation from Provincetowne/Portner = 56.50 Inv. Elevation = 54.50 TW = 2.0 Ft. = Ho L = 50 Ft. H2 = ..55, S = 3.13 % H100 = 4.5 HW2 = 2.0 + .55 - 50(.0313) = .99 (Inlet Control Governs) HW100 = 2.0 + 4.5-50(.0313) = 4.94 (Inlet Control Governs) �Q2 = 4.2 cfs Q100 = 4.5 cfs Q2 = Q100:= 20.4 Culvert 1 Q2 = 35.00, Try 42" RCP Inlet Control HW/D2 = .78 HW/D100 = 1.0 Q2 = 29.80 Q2 = 35.00 Q100 = 35.70 Q100 = 51.00 Q100 = 51.00 HW2 = 2.73 Ft,. HW1.00 = 3.5 Ft. Outlet Control L=50+ S = 0.40% H2 .4 ho = 3.5 Ft. H100 = .78 ke = 0.5 HW2 = 3.5 + .4 - (.004)(50) = 3.70 Ft. HW100 = 3.5 + .78 - (.004)(50) = 4.08 Ft. Outlet Control Governs KLI Sta 62 + 21.69 cont'd Culvert #2 Try 42" RCP Inlet Control ' HW/D2_ _ .70 HW2 = 2.45 Ft. HW/D100 = .80 HW100 = 2.80 Ft. Outlet Control L = 75'± S 0.4� h02 = 3.70. H2 = .40 ho100 = 4.08 H100 = .40 ke = 0.5 HW2 = 3.7 + .4 - 75(.004) = 3.8 Ft. HW100 = 4.08 + .4 - 7.5(..004) = 4.18 Ft. h, Culvert #3 Try 36" RCP Inlet Control 11 W/D2 = HW/D100 = .70 Pa Outlet Control Governs HW2 = HW100 = 2.10 Ft. Sta 62+21.69 cont'd Outlet Control L = 50'± s = 0.4% H2 = .4 Ke = 0.5 H100 = .40 h02 = 3.8 Ft. ho100. = 4.18 Ft. HW2 = 3.8 + .4 - 50(.004) = 4.0 Ft. HW100 = 4.18 + A.- 50(.004) = 4.38 Ft. Culvert 04 Try 18" RCP: as Q2, Q100 very close, check Q100 only. = Inlet Control HW/D100 = .80 HW100 = 1.2 Ft. Outlet Control L = 130'± s = 0.40% H100 = •40 kc = 0.5 ho100 = 4.18 Ft HW100 = 4.18 Ft. + .40 - 130(.004) = 4.06 Ft. HGL at Flowline during Major Storm. Check Additional Culverts @ Sta 15+59 Use TW = 3 Ft. HW = 4.56 Ft. � Q100tiist. = 228 cfs . Required additional capacity 228,2 27.3 = 200 cfs (Approximate) Try 42" RCP, ke = 0.51 L = 130 LF, S = 0.40% Allowable H: HW = H + ho - SOL' 4.56 = H + 3 - (.004)(130) H = 2.08 Ft. �,- Capacity - 77 cfs OK - Use. 3-42" RCP Check using Q = 67 cfs,.,, S = 0.49% H = 165 Ft. HW = 3 + 1.65 - (.0049)(130) HW = 4.01 OK Check Capacity with HW = 5.25 Ft. 1.5 = HW/D ratio 5.25 = H + 3Ft. - (.0049)(130): H = 2.89 IM Capacity = 90 cfs/barrel = 270 cfs 1.2(228) 1.18(228) Adequate L FINAL DRAINAGE & EROSION CONTROL REPORT FOR REDEEMER LUTHERAN CHURCH AT SOUTHEAST CORNER OF BRITTANY DRIVE AND TRILBY ROAD FORT COLLINS, COLORADO MARCH 2, 1992 (REVISED MAY 20, 1992) PREPARED FOR: REDEEMER LUTHERAN CHURCH. PREPARED BY: PARSONS & ASSOCIATES CONSULTING ENGINEERS 432 LINK LANE PLAZA FORT COLLINS, COLORADO 80524 (303) 221-2400 PROJECT NUMBER: 92.01 LUT 1 EXISTING CHANNELS Existing graded channels exist along the east side of Brittany Drive and along the south side of Trilby Road. These channels were completed to drain ' Basin D-2 0 8.30 Acres) as identified by the Provincetowne/Portner S.I.D. Final Drainage Report. Undeveloped 100 year flows were calculated to be 14.2 cfs ' from this Basin at the southwest corner of Brittany Drive and Trilby Road ' (Design Point 9). The existing storm sewer in this area intercepts street flows and provide inlet points from future detention ponds which will be constructed ' along the west side of Brittany Drive. ' The existing ditches have capacity to convey not only the undeveloped 100 ' -year runoff 0 4.2 cfs) but also the developed 100 year runoff (61.2 cfs). The existing section along Trilby Road has an estimated capacity of 80 cfs. These ditches are unsightly, do not fit the proposed development and due to the slope and erodibility of ' soils in this area would be impossible to maintain. Based on the analysis and guidelines provided by the Provincetowne/Portner ' S.I.D. it is anticipated that these ditches will need to convey the undeveloped 100 year runoff of 14.2 cfs. Contributing areas to the south and west such as Somerly at Provincetowne will. provide detention for their developments and releases only 100 ' year undeveloped flows. To convey these flows and eliminate erosion problems a -7- II 24" storm sewer has been designed to replace the open channel. This pipe will be constructed at a 3.0% grade which when flowing full will handle 40 cfs; considerably more than the undeveloped 100 year runoff of 14.2 cfs. A grassed overflow channel will be provided as additional protection should inlets plug. A easement has been provided for the proposed storm sewer: OFF -SITE FLOWS Runoff from the west and north of this site are identified in the Provincetowne/Portner Drainage Report and are conveyed by street improvements and adjacent channels easterly to South Lemay Avenue. Runoff to the south and east of this site sheet flow away from the site and except, for a .7 acre parcelimmediately south of this site, have no impact on this site. ON -SITE RUNOFF Water will be routed through the site via the proposed parking lot storm sewer and drainage swales into a detention pond. This includes the entire site 0 1 1 1 1 1 1 1 1 1 1 1 area including a .7 acre area immediately south of this site. All of the runoff from these areas is routed to the detention pond. A temporary swale along the eastern edge of the site will insure that no drainage flows will impact lower property to the east. SEDIMENTATION/DETENTION POND A sedimentation/detention pond will collect flows from the entire proposed development site. These flows will be detained and a 100 year historic runoff will be released into the ditch along the south side of Trilby Road. The release of The 100 year historic runoff is provided for in the drainage analysis completed as part of the Provincetowne/Portner S.I.D. EROSION CONTROL WIND EROSION. This site is located in an area designated as having moderate wind erosion potential. The existing natural grasses provide adequate ground cover in NOTES: nry ma a RREr N1e 1, M MUT> M HLOT (INANIMATE 9MYATIC ITONAL MMIE TO NATION TIME SOVIET ClAPM`SCALE 9MN AT 3j• M�Oe ' II I I F w M LOT MU R LIEET Ift NO gMPM S116CXII6.W0 MM]5 TO M HEM _ _ _ ^ \I,� .. AT A MINIMUM RR Ipl l)Q NL M31[DftM159W1 B[@Nm I I sTNALNROR nu TIOAtlE°up M rulLav ._ ANY FIRM WER� IY WRAP MATFOUNKNTw sECFFIMMIGRANT N emu TO PRESERVE OaND naA PATTERNS A I Na - IN 0_ u9 YNS@ W4RS4eLv aR w[M6 _ _ _= � z Tl \ uc1. SMALL WE (WINES wxT n WE NNE x. R& a OL" . OM,EP•S A9RGA.TIW I'm GREW gML M/MM:, IF OIEII6 x1' RW SM CHANNEL DROP S TF ACI a SMALL WE A MUL - A wy Rwmvn IS a _ SEE OETPE- —_—_—_ YE STRUCTURE- S 6' VnIITV ANT.IEEO W M PEER x1O SMALL NdIKE A Y/wxET . NLET I 0 MANAGE EAVETIr a Olun LAMBERT .N vww. - __— __ ¢-Aaron EASEMENT _ 1 0 xA' RCP a zeF / • ms xN' wW (TYPICAL) ar' R. Au Mn SAUL a OvvED BY A aAa1ET NAMAE I.M IV RIPRAR uAr 1 1 zTec` Tiller AND �w.¢ass AND urooArzD uaw°tE / �u xNau I IY u,utt R fE 93e S. ROM m nlvlm N w AND MP1N rxNAATIMs REDEEMER LUTHERAN SITE I a MANAGE rm aARu WADIr a AmN H \ FASE)ENT x rT2Y _V`w. k II EXISTING PIPING LAYOUT NOT T TO SLUE 29 ;'t 1Y-vs�l. o� _ _I"20' UTILITY -I 11 a&�AAGE i \ \ 2 / > ?% <' 3y" %1=E uwu .rm 1 I I ' §rs%�..�. / ,r s-1 "/ EwnLur �weo ,i' I 1 REROUTE �� D �`.`E-8 /, war° ' 6'1l w D i�i`�A Ra.e I ( j att wTxu PrtoL+Ra,eYrc M }YAwic WRIM 4ia1 wD I III' IRm"MON �. IIpE _ J '11 RERd11E RAGAnM j •D/ 7 oi�:• \ - _os,_ PROPERTY Lm4S 6xLr BARAN p0 vRoncnw / Ie zd "unuTr I qO_o- -� \ � r-A-sds �nWF 1'��RE umDivrµ p - uguE�oN `Jrx'ge.sl .:t., II _----- - - __ _ _ _ _ _ _ _ REMOVE CITING RET, A, Nvrn 111 1 111 - _ a/14tx- _�iE«J_ i'r�s___ _________ __ ___ _ _ __________ _____'"�.u� 'll 1 I EI 19 RmWRO E4?°s; �R•PAx s Y y' ��-weo—______ __— ____ Ems__—________________ ____ - 41 mewnM ° Y PAN a oadL II xe' PEDESIRINL,. 1 1 L dTM I / _i 1 /' wn.a MAxxEL MM wm.O (SEE DETAE sxEET) LEYAY AVENUE r NOTE n Il II unL, a Mum- d unun I .. 'oy. RU145RR M M S,RuenlnE (SEE 4211 o AT BACK X �s EASnNL 11 1 EASFAENT al I EASDIwT _ _ _ I �I 3�r II // _ __ oET.LR, Mm 1,NA/Ie) WALK IN AREA sww Ax' RCP L6 _ - - `a el_ /� 4 L_EpveG.5 I so�f/ ,P DETENTION POND DETAIL 111 I I 1 I 1" - 1 \ E Ze e _ e SCAM T211 1 W-517 / /' /`� 4IV12 7 l)�elaJ I 1 a R 40 REMOVE Emnxc le' / 'PPPRAP 1 G _ _ _ e1 RCP a COME Imur; l 4E I L MOVIE / II 11 =5 1 Rr' _--a _F' I - Tsw RECONSPAINsPROC"'ITM OEruL ABDVE w I 7.'. .'re'RIPRw J� a4 (MEET u_/1°1. / /� '� IXv.msae OUTLET PI F i 011, I,11 11 Muo'W1Er=_i 11 i''� 111 1} TV // 1 e PAN t FA dro wrL_J --- _ _ sEEceuAE. 1 4.1y- ' i. r_°5- + ' aL9 I';�x -91FCT uA/le QI 1a r _ 1 avrxr �J l ay FE-tz.s I N- 64 % "=%i/ \) "SST(REP S _ NGIr ,111 ./ FIT �� lr Ex �'''�! ION 'R0 M" A�g 1 " }8,3�i I9g �.t}64 / I �1�1 THIS INNDCc1) MVnu ( - (irPICAL) al ASE1 NO VIM `d2 1 1 I vs- 5-' Y='-oa{lfyos I Q /.A9. / '. V7 i �^� // / !I II II IEGENIL' ({ MquaETP ROTccPoll 11 11 - _ I _ q. - es rt ys A ai �y ', / ' / 531,--� ( 1/,1 / III, 1 _ _ _ - _ EnsnNG z' CONTOUR 1 e5O.1p•. O t / sip c J _ �iis iea L / 14 II HNv ,a,s 1 Il i 11 fl I I I Efg4�; ' M I r �Bi B\ V E�/f" /, :% I _---_ r=-✓ \i / Q' EXISTING IS CMTWR _� iemJ 4�d*Sl 4•�9is• e 2 T '�� ti // _' 'I lwil "I{"- 1 y 1 ` t, 16-i'^P_.I v _ yy,, ' ,r e> �Y'AO PROPOSED CONTOUR wL.,zol a - 1871� it //'' / I III xIM Pdxr ii-" ' G1,� ti / I 1 I 90 LOT NUMBER w/ DESIGNED .. e.91'A*AAnA 11 TRmca 119 Ooi'� 1 e yyii B> a �_� Er-s45.' J \ �' p,, V, b - - �I `'-'' I ...a I M$Tj �'-sy'�w'' oL -11.y� /i/ _ ..,9 �II II ET -eta FINISHED a°M ELEVATION IE 7✓� /�II, _!" � .-./'i/% II • -'E sEMYo i i APPROXIMATE euIlnlNc ENVELOPE APPRDAYAIE J i� A' Mf]E I iT S65 . I 9A° yp� 1 i I I DROP STRUCTURE (SEE SHEET • BIDG. EHYEIM / e,U� t L L— L _ _ jif II Fl,' " _ 3 �/ �� ,'I I Is" _ _ I1 a uzul'r o-E_' ,J / �I I --� lu roR Execr Locena+s ��� 77�'.' 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A / ., > I I Tcv' _" ,II1i1.1 {fl' I i I�� - 11 ___ 1 ♦' i117 - . yy, Yti r'E EE�,A6o .o-e r ✓' ei> "o III i'i l v / 7 oil r- <S8, S' /L'- I 5 1 4 _ / FIN"9�' N 72� / I II l il'o fW i�ITE'wAmE "--s Iz'unux ! .5 / C. k-xBa4 I R.ens - �iE><5as / �i' TRACT 'B'' n- I II III _ J ` EAxMOI 48 D / ' A o - e ..��� ' �_ rya' //l/�.`; ` 1/ Mun-EAMNLY E -W4.1fi_ Ill l��HIMAINALE L // �a /Tii5 - -A' c557, �� / / { r 4910S I III 1III a unun ( EASEMENT / e! /,N . i KsKs r2.1es J .e �.{ \1 / � - 1 raj Il Id / •_if 1 1 a .,CMCjLIE 16,' (I ,' �v°v'Y2z• �' "E 521 a ,r_X:7 I ^ 55', r�.n5' // / `ar MTUL�ABSSSOVE' li / III 9 I swaynERi h' _c `Mmw N.S�� 1 5�� ii 54i znO53u I \ za'lII'z0' RIPRAP 15 ' k--IS. 15M1lY'MAP a5 \\ r - n-a,IS I' I I 3-b' J .I W1LLi PR°1ECTdl .. Itl.W i 1 5p ..%I' FARRAR 11 \ �'� sz� IV uxA Er. w.s m �J 1a I OUTET Mo�FC11M REAR es° - le' 2' CONC. / Is RAN. SEWER. MUNAM _ EXT I MD - Ir ART A syso ,y -- - _ _ _ _ —_,r_ __ - - NET w r - - _ - —__ ___ -- _ _ - -- _ _ - _ _ TEE 1 T INV SSte 911PE FASf]RIT NY�A m/ — SEE SHEET B EM MORE O A2 RM 'APE # EEET `1!' RM . m.s.n.ays.c-....�..._..:.7' DETAIL AREA _ _ RnpORli � _ _ �L-O. -.-. LEILIY AVENUE - - '� -s MET LT"Flp. MV NT -- — — — 1X°III J ----��MAR 301994 No. Raisin Den: Pm1eDL Sleet PARSONS & ASSOCIATES, INC. 92.21—KEN PRO VINCETOWNE P. U.D. / 452 Link lane Plana Roa)aY: - tad' (or m noted) CONSULTING ENGINEERS et Collins, Colorado e0524 ueakoer. cod =kar. nP (sos> zzL—z400 a �,N� o.U: n Nk D, IBD4 DRAINAGE &GRADING PLAN law x x^ r aw rMAM cc;IM9. itL L ° affair_ rv1 PTYcnM 1 RY a AM -� Me r Ca:. A -A Pm m. CHANNEL DROP PARAMETERS UNIFORM RCIX SEE 1.S R - BASIN DEPRE M tT Ut - tliaTD ROCK APPNWCH la W - BAMN LENGTH (GROUTED) 22• LL - DOWNSTREAM TRANSITION tp Lt - LEMON CE EµL (GR Mn9) M. xa - MCV HEIGHT 4.1' D9 - GRDJT THICKNESS vC W -WANNER BASE N 1V IN - CHANNEL BAY MDIN 1O P1AN CHANNEL DROP DETAIL NOT TO SOME LPM1 xATIRAL PIL, MAOE� / 915- / EE 100.0 I ELEVATIONS ARE FOR REFERENCE ONLY TYPICAL LOT GRADING PLAN NOT TO SCALE TABLE F roNsrRxnoN saWarca PIrorzR PM19 At OONLY nU.n 21Muum mtB c 4WEx0 INwWIP.EIEO or. 4a OYMIL 0.2 _JtlAiBL vN.l. MM.aMm em MotorM a.a,M ley" E tinWIN as er wNAMAe b u M )Inthe CRY"Amr ked YEAR MIAMI Man )HRLOT CRAONG M UTDTES Mo ENCHUm CONTROL Sol Roping pa,therawr Ayd I mR eaWARREN, SlSeamy Clew YANFAU. EROSON CONTRO SSw meet Nobel, BaM FBmWe Silo Slit Fm[e 9v Sane Begs Be,, Be i� Rafufra1e1pa" "ow - - Other °h9 rEOTATVEFornryinen.t s.a PImlF9 M'IchlTwnpumY�nTI 7 ling SOE n alct T lettflngl/ Mole/ BimMa CRY, I 1 TABLE 2 ERASION MWML Y671AODS GWION CI TRUL iffiflayLIE C-FACTOR -FACIW VAWE STRw BILL Chy 1.0 9M AD. OVN65 N I ci &SHM7 PAVEMENT am IN ROwW.Ln STRAW Ld AAl eS01KBFD ARFAt fSTS/ vVY FDA6cs am IwOlsnKmm uA54s S ' ' YIZt �I IY1S N50 r 6 d NS9 '~ • O.NOr �l M PIES III OAR/IF Od'Y �L�J WHW PROFILE OF PIPE AT PEDESTRIAN PATH FROM LEMAY AVENUE TO SOMERLY LANE SECTION "S"—"S" LOOKING WEST, FROM SHEET 9 SEED MIX (ALL OSTMBED AREAS) RECOMMENDED w%ED POHIDS OF PEACENT POUNDS OF SPECIES PUS/ACRE OF MI% KS/ACRE MIESCENT MXEAICAA55 21.8 b 9.8 SMOOM NONE 11 35 56 SIDEDATS CAAMA log w 2D IDEAL 100 RG SEED MIXTURES FOR SITES MN OSTMCIVE SOH PRCBUEMS (E C. ALKAUNITY. SALINITY DR MIN WATER FARE) SHWLD BE DEVELOPED BY A TRAINED SPECIAUST MULCH (Au DISTURBED AREAS) ME ON MINE OF THE FOLLOV NG MULCHES SHALL W USED AN A PERENNIAL DRY -AND GRASS BEER MIXTURE. ACCEPTABLE MULCH DALES CE USE APPUCATW RAT XTRAW ON HAY JAN, III- DEC. 31 2 TWS/ACRE DRAUUC (WOCO OR PAPER) MAN. 15 - MAY 15 2 TOMS/ACRE EROSION CONTROL MATS FAR BLANKETS) JNN. 01 -'DEL 31 NOT APRIGBIF IMY a 9rAARIIBm4 m gE �6 HYDROUS REELS AND AT UEAST 50% M11TI'ENAIR�E' xAY A NA1K M/.II IS SD�sTEPD Dlxc MDLCHING MAINMAU. IF AVAILABLE. FERTILIZER REQUIREMENTS (Au OSTURav AREAS) I. 91ES WALL BE FFFDUND ACCMOW TO LABORATORY SOL ANALYSIS AND RECOMMONCIATM. 2 IF APPROMED BY THE City OF FORT COLNS, IN ABSENCE OF A SOL ANALYSI5Or V'NIMUM OF Q AILABIE PHOSPHORUS S OF LL BE APPLIEDAVAILABLE I FIR AC E, BONDS ANDY b 10 GRAPHIC SCALE I I a MY i I make .INN o0 r "N s0e? -- �Ensnxct__ir 4980 pXRNIX ptltE I I .9] � EN511NC fES I I - �. (RFLOGT) J'_ _y l 6 IY 2FY4MPaCp�1.0Ot 11.00 li- 181 49]2 OPEy.Gllf"- xLP a SWS._ 10 RON a M24" Rf119E Cf fE9 19 91B.ECi iOIMSP[CTM '- i11Y\.NI::nN I:`J 2Y9tMOi_ __Pl..)♦1: PROFILE OF PIPE CROSSING BRITTANY DRIVE AT INTERSECTION WITH RUMFORD LANE 1+M �400 PROFILE OF PIPE AT ACCESS DRIVE BETWEEN LOTS 1 AND 2 (TO PROVINCE ROAD) HY MAIN a CAYYExt WAAe N9`Y J TRACT A PO4- IIYNER. A96D . 56 i - Le M1ENnM SSHEET EE DETAH. 1 DxuxA9E / a A/ $2 qqq —2" q III 15 M PED6smIAN EAYMFM 49 a 51 +°'I 53 54 '.55 w_ z 7.5 , 20ROMPRAP u TECTISSLUPE 1 6 r :rr'.'"" 1-4D SD A' nnUrC E _,p- I l �� IYPe rET RM I ND le• COrvC EASEIKMT w¢ IV wA¢ _e 4 II PAx .. --' _ .� 54 54.50 b �I __ INV SAVE If NVE LEMAY AP-- _ _ for z g 51T a D.4N JZD'e zME w' xiw w' MYDw 41' 9aW IF lawa z.aR U' +90 a z.Or 41' SBB' a DNA DRaR • zmE ORaP •{ zox MaP •Eyyzln MM DRM N+m, FwNReo+ MM{ _ q� { WBI 4968 W. RS \1 DATUBY' IIdV tlAM N!0 NM PROFILE Or PIPE AT ACCESS DRIVE BETWEEN LOTS 2 AND 4 (TO PROVINCE ROAD) START BTATONNG ("A 01401 _ j I � TwE'K IE W i In10' 1- : RCP ���{{FIII x "ET IS- RM tl. M/BAN_ L :IT. W 0151 xv W.31 / EMSTING i2e POPi' I 4976 F.OU - SE[ On1ER PAOFLE T _ r-\\ -`� li.. `b LF - IB' _ y RCP a 200% 49]1 i _ � t - 1+00 Dew a.x PROFILE OF PIPE NEAR INTERSECTION OF RUMFORD LANE AND BRITTANY DRIVF ww._._._._ F_.-R* W- -1 M40'- _Eii 3��1'a I I — ].B rLm 49]9 RW iSANE S 'i NM i f I I I I DAM 1+00 PROFILE OF PIPE CROSSING BATTSFORD CIRCLE NEAR LOTS 54 AND 55 SECTION A —A LOOKING NORTH. FROM SHEET TO I�FL N14.1� w19.DI L �34r Y I I I � J J ROM Cf LOCATION OF NORTH U34AY ASL DROP STRUCTURE PARSONS & ASSOCIATES, INC. "JIB 492 Link Lee PLM24 EERS CONSULTING ENGIN�- Collins, Colorado ease D41dp (303) 221-2400 Dra,9g 92.21—KEN - Io0' (or as now) :IO Cpetlkm: DP fP.YL. Mb: r..NA ER JEAN PROVINCETOWNE Po UBD STORM WATER DETAILS