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HomeMy WebLinkAboutDrainage Reports - 05/09/2014City of Ft. Collins veA Plans Approved By Date__ FINAL DRAINAGE REPORT MVG-MORNINGSTAR ASSISTED LIVING & MEMORY CARE Prepared by: Interwest Consulting Group 1218 West Ash, Suite C Windsor, Colorado 80550 (970)674-8488 Prepared for: MVG — MS (Fort Collins) LLC, A Colorado Limited Liability Company c/o MVG Development 1509 York Street Denver, CO 80206 April 23, 2014 Job Number 1173-105-00 t I INTERWEST = CONSULTING G R O U P April 23, 2014 Mr. Wes Lamarque ' City of Fort Collins Stormwater 700 Wood Street Fort Collins, CO 80522-0580 RE: Final Drainage Report for MVG-Morningstar Assisted Living & Memory Care Dear Wes, ' I am pleased to submit for your review and approval, this Final Drainage Report for the MVG- ' Morningstar Assisted Living & Memory Care development. I certify that this report for the drainage design was prepared in accordance with the criteria in the City of Fort Collins Storm Drainage Manual. I appreciate your time and consideration in reviewing this submittal. Please call if you have any questions. ' Sincerely, O�p0 RE(3 j r� l •°C 33441 jr iQ Robert Almirall, P.E. O�.''••...... ..••'' '+ Colorado Professional ss/ONALO ' Engineer No. 33441 L 1 C ' 1218 WEST ASH, SUITE C WINDSOR, COLORADO 80550 EEI. 970.674.3300 - fez. 970.674.3303 ' TABLE OF CONTENTS TABLEOF CONTENTS............................................................................................................iii 1. GENERAL LOCATION AND DESCRIPTION................................................................ 1 t 1.1 Location...........................................................................................................................1 1.2 Description of Property................................................................................................. 1 2. DRAINAGE BASINS AND SUB-BASINS.......................................................................... 2 2.1 Major Basin Description................................................................................................ 2 ' 2.2 Sub -basin Description.................................................................................................... 2 3. DRAINAGE DESIGN CRITERIA ' 3.1 Regulations ................. ..............:........................................................................ 2 3.2 Development Criteria Reference and Constraints...................................................... 2 3.3 Hydrological Criteria......................................................................... ............................ 4 ' 3.4 Hydraulic Criteria.......................................................................................................... 5 3.5 Floodplain Regulations Compliance............................................................................. 6 ' 4. DRAINAGE FACILITY DESIGN....................................................................................... 6 4.1 General Concept............................................................................................................. 6 ' 4.2 Specific Flow Routing.................................................................................................... 6 4.3 Drainage Summary........................................................................................................ ' 5. CONCLUSIONS....................................................................................................................8 5.1 Compliance with Standards.......................................................................................... 8 5.2 Drainage Concept........................................................................................................... 8 6. REFERENCES..............................................................................................................:....... 8 ' APPENDIX VICINITY MAP AND FLOODPLAIN MAPS.......................................:................................. A ' HYDROLOGIC COMPUTATIONS..........................................................................................B HYDRAULICCOMPUTATIONS..............................................................................................0 WATERQUALITY..................................................................................................................... D t iii 1 1. GENERAL LOCATION AND DESCRIPTION 1.1 Location The MVG-Morningstar Assisted Living & Memory Care development is located in southeast Fort Collins. It is located in the Southwest Quarter of Section 30, Township 6 North, Range 68 West of the Sixth Principal Meridian, in the City of Fort Collins, Larimer County, Colorado. See the location map in Appendix A. ' The project is located west of Lochwood Drive, north of E. Horsetooth Road, and bounded on the west and north sides by existing residential lots. An existing drainage ditch with an existing 25 ft Drainage Easement runs along the west edge of the property, tdividing it from the residential properties. ' 1.2 Description of Property The property consists of approximately 4.42 acres of land. The existing land currently drains from southeast to northwest at approximately a 2% grade. The land is currently vacant with mild sloping terrain and covered with natural dry -land vegetation across the ' entire site. The only offsite flow entering the site is through an existing concrete drainage ditch originating at the Southwest corner of the property and conveys runoff to the ' northeast. There is an existing 25' drainage easement accompanying the existing concrete ditch, extending from the existing flowline 25' to the west. An additional 25' ' drainage easement is proposed, extending from the flowline 25' to the east, to make the entire Drainage Easement 50' wide up to the Tract A -Utility & Drainage Easement. The channel is not mapped by FEMA, but the project is located in Zone X of FEMA FIRM ' Panel 08069C 1000F. The Geotechnical Report and Supplemental Memorandum by Kumar and Associates dated November 12, 2013 and December 10, 2013, respectfully, indicate the presence of ' groundwater at approximate depths of 8 to 9 feet below existing grade. However, based on the recommended drilled pier design, a building perimeter drain system is not required. The poorly draining onsite materials do present the need for a supplementary underdrain ' system for the proposed site LID's. ' 1 u ' 2. DRAINAGE BASINS AND SUB -BASINS ' 2.1 Major Basin Description ' The proposed development lies within the McClelland's Creek Master Drainage Basin. The entire site currently drains to an existing concrete drainage ditch along the west and northwest property boundary. James H. Stewart and Associates performed a drainage ' study on this drainage in March of 1978 and determined the 100-year storm to produce 217.0 cfs. However, the updated 2010 SWMM model for the basin shows a 2-year storm ' run-off of 20.6 cfs and a 100-year storm run-off of 150.2 cfs. See Appendix B for existing site hydrologic computations. 2.2 Sub -basin Description ' The existing site has a historic runoff of 1.7 cfs and 6.7 cfs for the 2-year & 100-year run- off event, respectively, with a historic 2-year release rate of 0.39 cfs/acre. The site will be ' divided into 2 sub -basins for proposed construction activities. Sub -basin A will consist of approximately 1.24 ac and will be collected in a small extended detention basin located ' southwest of the proposed building before releasing into the existing drainage ditch to the west. Sub -basin B consists of approximately 3.18 ac and drains to the northwest corner ' of the property where it will be collected in a second extended detention basin before releasing into the existing concrete drainage ditch west of the property. Once the run-off enters the existing ditch, it will flow northeast eventually reaching McClelland's Channel. 3. DRAINAGE DESIGN CRITERIA 3.1 Regulations ' This report was prepared to meet or exceed the "City of Fort Collins Storm Drainage Design Criteria Manual" specifications. Where applicable, the criteria established in the ' "Urban Storm Drainage Criteria Manual" (UDFCD), developed by the Denver Regional Council of Governments, has been used. 3.2 Development Criteria Reference and Constraints ' Urban Drainage and Flood Control District (UDFCD) recommends a Four Step Process 1 2 for receiving water protection that focuses on reducing runoff volumes, treating the water quality capture volume (WQCV), stabilizing drainageways and implementing long-term source controls. The Four Step Process applies to the management of smaller, frequently occurring events. Step I: Employ Runoff Reduction Practices To reduce runoff peaks, volumes, and pollutant loads from urbanizing areas, implement Low Impact Development (LID) strategies, including Minimizing Directly Connected Impervious Areas (MDCIA). See the LID Area Exhibit in Appendix D. ' Runoff for the site will be split around the proposed building's southeast corner to the ' west and north, respectively. Sub -Basin A ' Runoff directed to the west will be routed south of the building through a Grass Swale to an extended detention basin, herein referred to as "Extended Detention Basin A" equipped with a Water Quality Outlet Structure which will release flow into the existing ' concrete drainage ditch along the west edge of the property. Extended Detention Basin A will also be constructed with Gravel Dry Wells along the flow line of the basin to help slow the basin's time of concentration and serve as supplemental Low Impact . Development (LID) measures. Sub -Basin B Runoff directed to the north will be routed through another Grass Swale thereby reducing ' runoff from impervious surfaces over permeable areas to slow runoff and increase the time of concentration and promote infiltration. Runoff from portions of the parking lot shall drain across Pervious Pavers before entering a second extended detention basin, ' herein referred to as "Extended Detention Basin B". ' Step 2: Implement BMPs that Provide a Water Quality Capture Volume with Slow Release ' Sub -Basin A Extended Detention Basin A utilizes a Grass Swale, Gravel Dry Wells and a Water Quality Outlet Structure designed to allow sediments to settle while releasing treated ' flows at or less than historic rates. Sub -Basin B ' A Grass Swale located southeast of the main building entrance shall collect the down- ' 3 I ' spout runoff before conveying the water to the second water quality treatment basin. Pervious Pavers are located within Sub -basin B upstream of Extended Detention Basin B ' to help reduce total runoff by allowing water to infiltrate. Extended Detention Basin B also shall be equipped with a Water Quality Outlet Structure designed to allow sediments ' to settle while releasing treated flows at or less than historic rates. ' Step 3: Stabilize Drainageways Natural Drainageways are subject to bed and bank erosion due to increases in frequency, duration, rate and volume of runoff during and following development. Concrete pans ' shall be used to convey water from the paved and parking areas to Extended Detention Basin B. A concrete pan shall also be used at the outlet of Extended Detention Basin A ' and a concrete channel will be used at the outlet of Extended Detention Basin B. Rip Rap shall be used at the outlet of the on -site storm sewer system. The Rip Rap shall be ' stabilized in place. Step 4: Implement Site Specific and Other Source Control BMPs ' Proactively controlling pollutants at their source by preventing pollution rather than removing contaminants once they have entered the stormwater system or receiving waters ' is important when protecting storm systems and receiving waters. . This can be accomplished through site specific needs such as construction site runoff control, post - construction runoff control and pollution prevention / good housekeeping. It will be the responsibility of the contractor to develop a procedural best management practice for the ' site. ' 3.3 Hydrologic Criteria Runoff computations were prepared for the 2-year and 10-year minor and 100-year major ' storm frequency utilizing the rational method. The Modified FAA method was used to determine preliminary detention volumes for the proposed extended detention basins. ' All hydrologic calculations associated with the basins are included in Appendix B of this report. Sub -Basin A will encompass 1.24 acres, 38% of which will be impervious, and is tcalculated to have 2-year, 10-year, and 100-year discharges of 1.0, 1.7, and 4.5 cfs, respectively. Sub -basin B will encompass 3.18 acres, 47% of which will be impervious, ' and is calculated to have 2-year, 10-year, and 100-year discharges of 2.9, 4.9 and 12.5 cfs, respectively. ' 4 ' The water quality storage volumes in Sub -basin A and Sub -basin B were calculated to be ' 0.02 ac-ft and 0.06 ac-ft, respectively.. Water quality volumes for both basins shall be provided in the proposed designs of Extended Detention Basins A and B. Final water ' quality volumes are presented in the Appendix D and calculated using the method recommended in the "Urban Storm Drainage Criteria Manual". ' 3.4 Hydraulic Criteria ' Using methods described in the City of Fort Collins Drainage Criteria, it was determined that Sub -basins A and B are required to detain 0.11 and 0.36 ac-ft respectively, in ' addition to the water quality volumes referenced in section 3.3 of this report. Sub -Basin A The proposed Extended Detention Basin A meets the water quality requirement for ' storage at elevation 4968.50 and the 100-yr storm detention at elevation 4969.70. A 5 foot long spillway shall be constructed at elevation 4969.80. A water quality outlet ' structure shall be utilized in releasing flows at or below historic rates into an 18" RCP culvert that shall discharge into a proposed concrete pan before entering the existing ' concrete channel along the west boundary of the site. Sub -Basin B ' Runoff from the existing adjacent roadways shall be collected in a proposed Type `R' Inlet along Lochwood Drive, south of the northernmost Morningstar site access. This runoff will be piped in 18" and 24" RCP pipes in the site's storm drain system to the ' Extended Detention Basin B. Downspout runoff from the southeast portion of the building as well as that runoff adjacent to the southeast portion of the building will be ' collected in a small proposed rain garden infiltration area before entering the site's storm drain system. Runoff from the parking areas and the runoff adjacent to the northeast, ' north, and northwest sides of the building shall sheet flow overland toward Extended Detention Basin B. tThe proposed Extended Detention Basin B meets the water quality requirement for storage at elevation 4964.50 and the 100-yr storm detention at elevation 4967.00. A 13 ' foot long spillway shall be constructed at elevation 4967.10. A water quality outlet structure shall be utilized in releasing flows at or below historic rates into a 24" RCP ' culvert which shall discharge into a proposed concrete' channel before entering the existing concrete channel to the northwest of the site. ' 5 L All hydraulic calculations are presented in Appendix C and prepared in accordance with ' the City of Fort Collins Drainage Criteria. ' 3.5 Floodplain Regulations Compliance ' No work is proposed within an existing floodplain. 4. DRAINAGE FACILITY DESIGN 4.1 - General Concept The proposed MVG-Morningstar site was designed to treat run-off as close to the point - source as possible, while also minimizing the length of drainage routing to the most ' feasible extents of the site. ' The proposed site shall be divided into two sub -basins based on design points A and B. The proposed drainage design follows the existing drainage pattern of southeast to t northwest. The project will consist of an Assisted & Memory Care Complex building with a footprint of approximately 43,000 SF, a parking area for patients and employees, an access lane, sidewalks and landscaped areas. Proposed- site run-off is directed to a ' . series of LIDs and an extended detention basin at one of the two design points before being released off -site. Each extended detention basin shall be equipped with a Water ' Quality Outlet Structure, designed specifically for that sub -basin, to treat and release the run-off into the existing concrete ditch at or below historic run-off rates. ' Both of the extended detention basins serving as water quality basins shall also act as on - site detention areas for the proposed construction. The on -site detention shall hold the proposed 100-year run-off and release it at the historic 2-year storm release rate. 4.2 Specific Flow Routing ' A summary of the drainage patterns within each basin is provided in the following paragraphs. ' 6 L ' Sub -Basin A includes the southern portion of the property, excluding the existing drainage ditch, and the south half of the downspouts from the proposed building, and is ' approximately 1.24 ac. From the downspouts, flow will be routed through vegetated areas carrying flow away from the building or sheet flow over -top the sidewalk. ' Remaining Sub -basin A flow will be collected and routed through a Grass Swale along the south edge of.the property and two (2) Gravel Dry Wells in the bottom of.the ' Extended Detention Basin A, which is located just southwest of the proposed building. Once the run-off is treated, the outlet structure discharges into the existing concrete channel to the west of the site, eventually reaching McClelland's Channel. Sub -Basin A ' is calculated to have a 2-year, 10-year, and 100-year discharges of 1.0, 1.7, and 4.5 cfs, respectively. ' Sub -Basin B includes the remaining approximately 3.18 acres located northeast of Sub - basin A within the site, including the north half of the proposed building downspouts. A portion of the east side building down -spout run-off as well as that immediately adjacent to the southeast side of the proposed building will be collected in a proposed Grass Swale ' before entering the site's private storm drain system. The north side building down -spout run-off as well as that immediately adjacent to the north, northeast, and northwest sides of ' the building shall sheet flow to the northwest to the proposed Extended Detention Basin B. Parking and access road run-off will sheet flow to the northwest or enter the site's ' storm drain system, which also drains into Extended Detention Basin B. Several rows of spaces are proposed to be constructed with Pervious Pavers to treat small areas of parking runoff. Once the flow reaches Extended Detention Basin B they are again treated and ' released through a water quality outlet structure into the existing drainage ditch flowing northeast into McClelland's Channel. Sub -basin B is calculated to have a 2-year, 10-year, ' and 100-year discharges of 2.8, 4.8 and 12.3 cfs, respectively. ' 4.3 Drainage Summary The percent impervious weighted average of the entire site is 48.7%. All proposed site runoff follows existing drainage flow patterns while adding a level of water quality to the ' discharge. Drainage facilities located outside of the right of way (including the rain garden, water ' quality pond, proposed storm sewer system and the detention basin outlets) will be 7 ' maintained by the owners of the property. The property owner shall also be responsible for. maintaining the portion of the common drainage channel located on the subject ' property. 5. CONCLUSIONS ' 5.1 Compliance with Standards ' All computations that have been completed within this report are in compliance with the COFC Storm water Criteria Manual, the COFC Master Drainage Plans, and the COFC ' floodplain regulations. All floodway information is in compliance with Chapter 10 of the City of Fort Collins Municipal Code and all State and Federal regulations. ' 5.2 Drainage Concept ' The proposed drainage concepts presented in this report and on the construction plans adequately provide for stormwater quantity and quality treatment of proposed impervious ' areas. Conveyance elements have been designed to pass required flows and to minimize future maintenance. ' If, at the time of construction, groundwater is encountered, a Colorado Department of Health Construction Dewatering Permit will be required. ' 6. REFERENCES 1. City of Fort Collins, "Storm Drainage Criteria Manual", (SDCM), dated March, ' 1986. 2. Urban Drainage and Flood Control District, "Urban Storm Drainage Criteria Manual", Volumes 1 and 2, dated June 2001, and Volume 3 dated September ' 1999. 3. ICON Engineering, Inc., "McClelland's Creek Master Drainage Plan Update", ' dated November 20, 2000 (Revised March 2003). 4. Kumar & Associates, Inc., "Geotechnical Engineering Study Proposed MVG- 8 Morningstar Assisted Living and Memory Care Facility Northwest Corner of East Horsetooth Road and Lochwood Drive, Fort Collins, Colorado' dated November 12, 2013 and a Supplemental Memorandum December 10, 2013. Lt APPENDIX A VICINITY MAP, AND FLOODPLAIN MAPS A SECTION 36 re I Wn go-go WE Es WIN Hill■ ■� Ism IN M is aI o 1 l :I ml COLUNDALE GOLF COURSE �IIm1lllllll �� •• mill going ■ 1 ■ i� �i i ' IIII111III�on m _._ -' ..1._�.�..w�� __.�..... a ._ofi.!i ._•- �, lam i_�. MVG MORNINGSTAR m VICINITY MAP SCALE: i "=1000` t 1 Y Y O Cr g N bLL$QO� y C N N m Y Y m W v Ccl —_ — Lm a a W _ n m T, m m V J Q J U 0 '• Y a Z U d 3 M1 L LL p� C Y to mma a LU W Ra U p v H (•_..y N d m ct y■ QlL co m `p W } W g m a �6 T la i9 w '- � nnrwa m c �. a M \ as »` ��. � v.n-•-, = m E �rn ui 2 .. N EL Lli !.- .I bs a N fL 7 p ga m E E c �v 3 d w R J fl Jn pf P 1 ern _ — C - � a N o i sarwsr , a r j 3 CL - Tl�l... L L cb aG m t� N C � nl to U i N p o � U APPENDIX B HYDROLOGIC COMPUTATIONS I I I I i \ I I I / I I I I 4 111 l i y I I I I I I I I DRAINAGE SUMMARY TABLE l CALL UTILITY NOTIFICATION CENTER OF COLORADO 811 GALL 2-BUSNESS DAYS IN ADVANEE BEFORE YW DIG. GRADE. DR EXCAVATE FM THE MMXING M UNOERGRMIND MEMBER UMTMS. 40 20 0 40 SO SCALE: I"= 40' LEGEND EXISTING MINOR COWOIAR '� EXISTING MAJOR CONTOUR �wA�w. PROPOSED M INOR CONTOUR �NIAIHr PROPOSED MAIOR CONrd1R PROPOSED DIRECTION OF OVERLAND FLOW PROPOSED DRAINAGE BASIN DMDE LINE A DRAINAGE BASIN ID MAJOR STORM RUNOFF COEFFICIENT DRAINAGE BASIN AREA ACRES CONSTRUCTION ENTRANCI O EF` SILT FENCE p_I 1 P_2 O BTORM DRAIN INLET. PN� U - I EXTENDED DETENTNDN( MMEWATION BASIN) INLET PROTECTION WATTLE (SWALE.O CH. OR VEGETATED FLO UNI WATTLE (GUTTER PROTECTION) NOTES: ). 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Sim MAIIW w Ivy VEGEYATONTIIAOMO DONMA m TO RTBIV•I®BY ®BY BD mm SA311, ED MPROV®BY LNAEB OdNtt b1 PROJ-NO. 11 7810600 9 1 1 1 1 1 1 1 1 1 1 1 1 Table RO-11 Rational Method Runoff Coefficients for Composite Analysis Character of Surface Runoff Coefficient Streets, Parking Lots, Drives: Asphalt 0.95 Concrete 0.95 Gravel 0.5 Roofs 0.95 Recycled Asphalt 0.8 Lawns, Sandy Soil: Flat <2% 0.1 Average 2 to 7% 0.15 Steep >7% 0.2 Lawns, Heavy Soil: Flat <2% 0.2 Average 2 to 7% 0.25 Steep >7% 0.35 (4) A new Section 2.9 is added, to read as follows: 2.9 Composite Runoff Coefficient Drainage sub -basins are frequently composed of land that has multiple surfaces or zoning classifications. In such cases a composite runoff coefficient must be calculated for any given drainage sub -basin. The composite runoff coefficient is obtained using the following formula: Y,(C, * A; A, Where: C = Composite Runoff Coefficient C; = Runoff Coefficient for Specific Area (A) A; = Area of Surface with Runoff Coefficient of C;, acres or feet- n = Number of different surfaces to be considered At= Total Area over which C is applicable, acres or feee (5) Anew Section 2.10 is added, to read as follows: 41 (RO-8) RAINFALL INTENSITY -DURATION -FREQUENCY CURVE 10.00 9.00 8.00 M 0 7.00 m L c 6.00 i 5.00 W f 2 4.00 J Q i 3.00 Q K 2.00 1.00 000 0.00 10.00 20.00 30.00 40.00 50.00 STORM DURATION (minutes) 2-Year Storm - - - 10-Year Storm 100-Year Storm Figure RA-16 City of Fort Collins Rainfall Intensity -Duration -Frequency Curves (13) Section 5.0 is deleted in its entirety. (14) Section 6.0 is deleted in its entirety. (15) Section 7.0 is deleted in its entirety. (16) Section 7.1 is deleted in its entirety. (17) Section 7.2 is deleted in its entirety. (18) Section 7.3 is deleted in its entirety. (19) Section 8.0 is deleted in its entirety. (20) Table RA-1 is deleted in its entirety. all 60.00 k L ° & /— k �\ § (\ E F( k / \� z \ k5 (/ = kR )E ;AI§ (j §a . e£ / \\ $& 22 (wE \\ \)/§ cc! £ ) K/ a\ q» 2«� (§\ \\ . (k\ (k §§ !« . / f \ . \■k /)]\. ;%|— ® �0 # \))a \}/\ \ \ /\kk 0.5 E\ f-Z 2 =.C5 < )led \� \ ] C 9 ! a W Y N N � y Z i 0 ¢ r O Q 2 x Z W aU ai Z O U LL O W F N Y Q f W o J z E O O m C O = E N � Q o m = IUu Q m t N v U 2 H 0 7 Oi �O vi - N o 10 Of lV O O � m 3 O J LL O O J a S U O ¢ O ¢ o fV LQ W w s n J ¢Q F l7 m E `O O O IV fV m O o � N` L N < l� 2 J w m r W > � o Q C U i7 W F � Z _ F N � m � N z a z ¢ m Q m N = z N F o a � a N m (0 c m c of .N m N C_ O U 0 LL O U O cm ,ci N �l LL O N C C. N N O U � O N L =' 3 LL c A ❑ O d _ ,y -0 O c N N w E m -e o � O _ c N a U m m-0 E + E J O Lo U O II E 0 U o M C_ > E E Z E O y 00 11 d 1 1 1 1 1 t a LU N O N Z O Q ❑ It ¢ F 2W a U NO U LL O W 2 F Y i R o _ = LL E �' O a _ m � m O N � O _ � E m U .. p W J m W C 0 7 r a LL O fO W m N N N = w 'c m m U of 0o 0 w F m O N N p 06 ap y^ w N ` c <m N m J J v ¢ = H c n m O O N2 v L_ m ? v 10 N N �m m J ❑ J ¢ W G O > O U � _ a W F � z r e N m C6 m N Z w z a m < m 2 zo z rl < - m � IM 0 N ❑ ❑ N n R } r N � w Z oa O } O UJ z U N Z U LL O W 2 H N Y Q W LL' J Q U C Q � e 3 E O O N O � E m U O N o Y W u � U � � N _ C O U O LL � J W OR N N N a C CN C O m O U O O W o N w e �^ N `� W t O N N CJ j r o g: N 0 V 0 V N ` y L N N N m J U W a o T cn 0 OZ J U W m e O o 0 W t � E Z F v N m N m Nz m Q m N z Z m Q z U _ N Wo a U) a N C m � � � § f /g $ f cc >— cc ® { §k $ §§ cli z (]) <�LU \ LL &� )\ \)\Cc \a \ CO \ �0cy cu S L CO cc Cal ..•- ooa2/ \ /LL / \ o { ) a } 0 § � § cc Rƒ LLI §ƒ � a § q cc cc � cc \ itLU GEf; §=ACL —{{ §§ � kw 3$ CC <_ 2&! § b� )[ / {\S (}\\\o co \ CD \\(]] Ee —)« coc /\\3\ / / / \ § \ ( ) 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 LL LL O z Y a W ^ aCC W } O W c v J a z O a N Y Q uj W 2 Lq U O Q Q f O O y U Q Q w O c > E Lm � 2 O O Q�oa U 0 y N � _O U V N Q c C 1� t0 U C E � U v u�i U o 0 V m Q U N � M LL O 0 z m 0 3 N z z H a O Q m U w 0 N c d O d CD 7 U LL 0 E O N L N C U ID C Cn . C i co C c U U N m Q D U C m c E o O C C ccCL ctl O V �� II Q m CI N IL 0 m m y c ui O z O Q r N 0 N_ U w a No Text i 1 APPENDIX C ' HYDRAULIC COMPUTATIONS 1 t r 1 n k HM Vt James H. Stewart and .associates, ine. Consulting Engineers March 15, 1978 STORM DRAINAGE SWALE COLLIIMALE SECOND FILING.' The swale that exists at the Easterly side of Collindale, Second Filing will receive drainage from the following areas: Foothills Meadow Apartments - 16 Acres Warren Shores - 23 Acres North Shore P.U.D. - 10 Acres Warren Lake Park - 26 Acres Collindale, First Filing - 11 Acres TOTAL 86 Acres Of the above areas, North'Shore P.U.D. does have onsight detention and the Warren Lake Park will -not increase the runoff, due to development, to a great extent. The runoff "for a 100 year frequency storm would be as follows: Foothills Meadows Q = 0.8 x 4.2.x 16 54. c.f.s. Warren Shores Q = 0..6 x 4.2 x 23 =" 58 c.f.s North Shore P.U.D. Q '0.4"x 5 x 10 =. 20 c.f.s Warren Lake Park Q 0.4 x `5 x.26 = 52 c.f.s Collindale. Q: = 0.6 x 5 x'11 = 33 c.f.s., TOTAL = 217 c.f.s. The swale would be as shown below to carry the 100 year storm.' i7 / / 50X /.48Gf 50) l' A oaG" 23DG/-.S t 6,1 /Z' Therefore; it is determined that Buildings C, D, E, and F as shown on the site plan would not be damaged during 4,100 year frequency storm.... " ' a� l� Richard A. Rutherford, P.E. h L.S. OFFICE-214::ORTIMCACEs 0 P.O:BO\429 0 FORT COLUNS•COLORADO80i22 0 TE:UMIO\EAREA 30T.IS2.9321 ' Worksheet for Q100 West Drainage Easement Cross-section Flow Element. Irregular Section Friction Method: Manning Formula ' Solve For. Normal Depth ' Channel Slope: 0.00600 ffft Discharge: 150,20 fP/s Current Roughness Weighted Methr ImprovedLotters Open Channel Weighted Roughnes: ImprovedLotters ' Closed Channel Weighted Roughne Hortons Roughness Coefficient: 0.019 ' Water Surface Elevation: 1.53 ft Elevation Range: 0.00 to 7.85 ft ' Flow Area: Wetted Perimeter. 29.48 38.76 ft' ft Top Width: 38.63 ft Normal Depth: 1.53 ft ' Critical Depth: 1.55 ft Critical Slope: 0.00566 ftfft Velocity: 5.09 ft/s ' Velocity Head: 0.40 ft Specific Energy: 1.94 ft ' Froude Number. 1.03 Flow Type: Supercritical (-0+25, 2,15) (-0+02, 0.17) 0.025 (0+02, 0.17) (0+21, 1.55) 0.025 y ' (0+21, 4.55) (0+25, 5.35) 0.025 SB�'4""`•Q:l¢='•;:e;,t'3F"" _Yrs"s.�Ii a. ti +^uy � , ti's-,Fiiu3 tti 6 r :-. � d �1 �'. v "r> (�.. CHon.GeometrV >..%%•„, bw+U >a.5rc<� �s:. .X> h�, ...�1°tt. .:..rkJy us.�,. .J :v� +stY...awp,':.�1'.rt�'�+u�� ...�3 T1.:-�La�:. C Worksheet for WOO West Drainage Easement Cross-section -0+25 215 0+00 0.00 ' 0+21 1.55 0+25 5.35 r. IJ ' Cross Section for WOO West Drainage Easement Cross-section ' Protect Descnptloh Flow Element Irregular Section Friction Method: Manning Formula ' Solve For. Normal Depth Sechon,l)ata Roughness Coefficient. 0.019 ' Channel Slope 0.00600 Wit Normal Depth: 1.53 It t Elevation Range: 0.00 to 7.85 ft Discharge: 150.20 Refs C —38.63 ft T 1,53ft i V:5 N KI Interwest Consulting Group DETENTION VOLUME CALCULATIONS Rational Volumetric (FAA) Method 100-Year Event LOCATION: MVG MORNINGSTAR - EXTENDED DETENTION BASIN A (SW) PROJECT NO: 1173-105-00 COMPUTATIONS BY: MHM DATE: 10/1/2013 Equations: Area trib. to pond = 1.24 acre Developed flow = Qp = CIA C (100) = 0.49 Vol. In = Vi = T C I A = T Qo Developed C A = 0.6 acre Vol. Out = Vo =K Qpo T Release rate, Opo = 0.5 cfs storage = S = Vi - Vo K = 0.9 (from fig 2.1) Rainfall intensity from City of Fort Collins IDF Curve with updated (3.67') rainfall Storm Duration, T (min) Rainfall Intensity, I (in/hr) OD (cfs) Vol. In Vi (ft) Vol. Out Vo (ft) Storage S (ft) Storage S (ac-ft) 5 9.95 6.0 1814 131 1683 0.04 10 7.77 4.7 2831 261 2570 0.06 20 5.62 3.4 4098 522 1 3576 0.08 30 4.47 2.7 4887 783 4104 0.09 40 3.74 2.3 5454 1045 4409 0.10 50 3.23 2.0 5895 1306 4589 0.11 60 2.86 1.7 6255 1567 4688 0.11 70 2.57 1.6 6561 1828 4733 0.11 80 2.34 1.4 6826 2089 4736,- '` 0.11 90 2.15 1.3 7060 2350 4710 0.11 100 1.99 1.2 7270 2611 4659 0.11 110 1.86 1.1 7461 2873 4589 0.11 120 1.75 1.1 7636 3134 4502 0.10 130 1.65 1.0 7798 3395 4403 0.10 140 1.56 0.9 7948 3656 4292 0.10 150 1.48 0.9 8088 3917 4171 0.10 160 1.41 0.9 8220 4178 4042 0.09 170 1.35 0.8 8345 4439 3906 0.09 180 1.29 0.8 8463 4701 3762 0.09 Required Storage Volume: 4736 ft3 0.11 acre-ft detention.xls,FAA-100yr SW POND EXTENDED DETENTION BASIN A (SW) Proposed Detention Pond - Stage/Storage LOCATION: MVG - Morningstar PROJECT NO: 1173-105-00 COMPUTATIONS BY: MHM SUBMITTED BY: INTERWEST CONSULTING GROUP DATE: 10/1/2013 V = 1/3 d (A + B + sgrt(A*B)) where V = volume between contours, ft3 d = depth between contours, ft A = surface area of contour WO WSEL• 100-yr WSEL, SPILLWAY TOP OF BERM Stage (Elev) Surface Area (Ft^2) Incremental Storage (Ac-ft) Detention Storage (Ac-ft) Total Storage (Ac-ft) 67.0 0 67.1 0 0.00 0.00 0.000 68.0 1223 0.01 0.00 0.008 68.5 2433 0.02 0.03 0.029 69.0 3642 0.03 0.06 0.064 69.70 5386 0.07 0.14 0.136 69.80 6078 0.01 0.15 0.149 70.80 0 0.05 0.20 0.195 i oiai aiorage nCq U QLU1 aya 0.195 > 0.130 detention.xls Interwest Consulting Group DETENTION VOLUME CALCULATIONS Rational Volumetric (FAA) Method 100-Year Event LOCATION: MVG MORNINGSTAR - EXTENDED DETENTION BASIN B (NW) PROJECT -NO: 1173-105-00 COMPUTATIONS BY: MM DATE: 10/1/2013 Equations: Area trib. to pond = 3.18 acre Developed flow = Qo = CIA C (100) = 0.59 Vol. In = Vi = T C I A = T Qp Developed C A = 1.9 acre Vol. Out = Vo =K QPo T Release rate, QPo = 1.2 cfs storage = S = Vi - Vo K = 0.9 (from fig 2.1) Rainfall intensity from City of Fort Collins IDF Curve with updated (3.67") rainfall Storm Duration, T (min) Rainfall Intensity, I (in/hr) QD (cfs) Vol. In Vi (ft) Vol. Out Vo (ft) Storage S (ft) Storage S (ac-ft) 5 9.95 18.7 5600 335 5266 0.12 10 7.77 14.6 8743 670 8073 0.19 20 5.62 10.5 12655 1339 1 11315 0.26 30 4.47 8.4 15090 2009 13081 0.30 40 3.74 7.0 16840 2679 14162 0.33 50 3.23 6.1 18202 3349 14853 0.34 60 2.86 5.4 19316 4018 15297 0.35 70 2.57 4.8 20258 4688 15570 0.36 80 2.34 4.4 21077 5358 15719 0.36 90 2.15 4.0 21800 6027 15773 0.36 " 100 1.99 3.7 22450 6697 15753 0.36 110 1.86 3.5 23039 7367 15672 0.36 120 1.75 3.3 23579 8036 15543 0.36 130 1.65 3.1 24078 8706 15372 0.35 140 1.56 2.9 24542 9376 15166 0.35 150 1.48 2.8 24976 10046 14931 0.34 160 1.41 2.6 25384 10715 14669 0.34 170 1.35 2.5 25769 11385 14384 0.33 180 1.29 2.4 26133 12055 14078 0.32 Required Storage Volume: 15773 ft3 0.36 acre-ft 7:1 detention.xls,FAA-100yr NW POND EXTENDED DETENTION BASIN B (NW) Proposed Detention Pond - Stage/Storage LOCATION: MVG - Morningstar PROJECT NO: 1173-105-00 COMPUTATIONS BY: MHM SUBMITTED BY: INTERWEST CONSULTING GROUP DATE: 10/1/2013 V = 1/3 d (A + B + sgrt(A`B)) where V = volume between contours, ft3 d = depth between contours, ft A = surface area of contour WO WSEL• 100-yr WSEL. SPILLWAY TOP OF BERM Stage (Elev) Surface Area (Ft^2) Incremental Storage (Ac-ft) Detention Storage (Ac-ft) Total Storage (Ac-ft) 62.80 0 63.0 180 64.0 2168 0.02 0.02 64.5 3813 0.03 0.00 0.06 65.0 5458 0.05 0.05 0.11 66.0 7535 0.15 0.20 0.26 67.0 9287 0.19 0.39 0.45 67.25 9871 0.05 0.45 0.51 67.4 10235 0.03 0.48 0.54 67.9 0 0.04 0.52 0.58 I Otdl Jluldyu i icy .a vw.uyv 0.540 > 0.377 detention.xls I 1 1 1 1 1 1 1 1 fl 1 1 1 0 a N S c J o 0oto3l) �o a Iz- r N C ° N 3 a a J °w d J UJ oU) c Zt� E m o a E _ ° o o N O O p� U 3 °� C y I N N N N ��vv L aUi�: u�o Ian _ "yarn Cl) a = v c L 3 c 3_ v c;o r n n >�Z o o - .0 II II y N d i p ° °L N N E NQ II II II, > NaJ1 II II II > II II 11. D II m w 3om ^pd � '>p C o N as E 3 o u n ca O F., LI n U2J 19 �nm El) O O J O L d 0 N U OcAF Ica ° U c d y N m S d Em - cw �y�yq w O rom fA 2/6/2014 ' LOCATION: MVG MORNINGSTAR ITEM: RIPRAP CALCULATIONS FOR OVERFLOW SPILLWAYS COMPUTATIONS BY: MM ' SUBMITTED BY: INTERWEST CONSULTING GROUP Riprap requirements for a stable channel lining are based on the equation from Storm Drainage Design Criteria, City of Fort Collins, CO, Vols. 1,23 & 3, December 2011 V S01 = 5.8 ' (d,). (SS-1). where: V = mean channel velocity (tt/s) S = longitudinal channel slope (f Jft) ' S, = specific gravity of rock (minimum S. = 2.50) d5 = rock size in feet for which 50 percent of the riprap by weight is smaller Determine if riprap is required using Table 8-2 ' Longitudinal Specific Class of d, Min. Riprap Velocity Slope Gravity VS" Froude Is Rtprap Table MD-10 Thickness LOCATION (fUs) (tuft) of Rock (S, - 1)0'� Number F < 0.8 7 Table MD-10 (in) (in) SW DETENTION BASIN 2.8 0.005 2.5 0.87 0.70 TRUE VL 6.00 10.50 ' NW DETENTION BASIN 2.5 0.02 2.5 0.98 0.62 TRUE VL 6.00 10.50 I C RIPRAP2.xls ) \ � 2 as E 2�^ �«f . ©_ §)/» R \ 2> k /000 2q�� c > CO k E$ \ k �~ §2�t3$]\ k = 0 (D %k� .0 ao) QT § k L 2 & e � S\\¢)§&& tm 0 A�;LU--ja a -555a�\/ \_,.,, �� > Via« »2 »k \ \k \ /k § k § ) �\ \ «� k CU k\ �c § [) cc Zr .k �q § § wo \ . c } E & 0 2 f to ¥j >\ 0 J = a ^ cm 2=\/§ ± t�a±&2 \k�\ �a,(D 0 \o ��%t$O QatE3: .sS. oq \===3 KLo �c R/oc�> „ .,, \\ §2 \k \ ) e \ � \� 3 K e \k \F8 a \\E\ 2� � k� r .�® IL 6 t � a § k wLL qN A�q � 0 �3 j < E C 1 i 1 1 1 1 1 1 1 1 APPENDIX D WATER QUALITY f7 No Text Design Procedure Form: Extended Detention Basin (EDB) - Sedimentation Facility Sheet 1 of 3 Designer: MM Company: Interwest Consulting Group Date: December 6, 2013 Project: MVG - Morningstar Facility Location: DETENTION BASIN A (SW) 1. Basin Storage Volume 1, = 38.00 A) Tributary Area's Imperviousness Ratio (i = la/ 100) i = 0.38 B) Contributing Watershed Area (Area) Area = 1.240 acres C) Water Quality Capture Volume (WQCV) WQCV = 0.17 watershed inches (WQCV =1.0 ' (0.91 " 13 - 1.19 12 + 0.78. 1)) D) Design Volume: Vol = (WQCV / 12)' Area' 1.2 Vol = 0.0216 acre-feet 2. Outlet Works A) Outlet Type (Check One) x Orifice Plate Perforated Riser Pipe Other: B) Depth at Outlet Above Lowest Perforation (H) H = 1.60 feet C) Recommended Maximum Outlet Area per Row, (k) Ae = 0.1 square inches D) Perforation Dimensions: i) Circular Perforation Diameter or D = 0.500 inches ii) Width of 2" High Rectangular Perforations W = . inches E) Number of Columns (nc, See Table 6a-1 For Maximum) nc = 1 number F) Actual Design Outlet Area per Row (k) Aa = 0.2 square inches G) Number of Rows (nr) nr = 5 number H) Total Outlet Area (kO A., =. 1.0 square inches 3. Trash Rack A) Needed Open Area: A, = 0.5' (Figure 7 Value) A, = 35 square inches B) Type of Outlet Opening (Check One) x < 2" Diameter Round 2" High Rectanaular Other: C) For 2", or Smaller, Round Ooenina (Ref.: Figure 6a): i) Width of Trash Rack and Concrete Opening (W,,.) from Table 6a-1 WCO. _' 3 inches ii) Height of Trash Rack Screen (H�) Hm = 54 inches UD-BMP_v2.06.xls, EDB - SW POND 12/6/2013, 10:28 AM Design Procedure Form: Extended Detention Basin (EDB) - Sedimentation Facility Sheet 2 of 3 Designer: MM Company: Interwest Consulting Group Date: December 6, 2013 Project: MVG - Morningstar Facility Location: DETENTION BASIN A (SW) iii) Type of Screen (Based on Depth H), Describe if "Other" S.S. #93 VEE Wire (US Filter) Other: iv) Screen Opening Slot Dimension, Describe if "Other" I 0.139" (US Filter) Other: v) Spacing of Support Rod (O.C.) Type and Size of Support Rod (Ref.: Table 6a-2) vi) Type and Size of Holding Frame (Ref.: Table 6a-2) inches D) For 2" High Rectangular Opening (Refer to Figure 61b): 1) Width of Rectangular Opening (W) W = inches ii) Width of Perforated Plate Opening (W.. = W + 12") Ww� = inches iii) Width of Trashrack Opening (W,;v) from Table 6b-1 W�Nm _ .. inches iv) Height of Trash Rack Screen (HT HTR = inches v) Type of Screen (based on depth H) (Describe if "Other") KlempT" KPP Series Aluminum Other: A Cross -bar Spacing (Based on Table 6b-1, KlempT/A KPP I inches Grating). Describe if "Other" Other: vii) Minimum Bearing Bar Size (Klemp' Series, Table 6b-2) 4. Detention Basin length to width ratio I (IJW) 5 Pre -sedimentation Forebay Basin - Enter design values A) Volume (3% to 5% of Design Volume from 1D). acre-feet (3%-5%of Design Volume,(0.0006 - 0.0011 acre-feet.) C " B) Surface Area acres C) Connector Pipe Diameter inches (Size to drain this volume in 5-minutes under inlet control) D) Paved/Hard Bottom and Sides yes/no UD-BMP v2.06.xis, EDB - SW POND 12/6/2013, 10:2B AM Design Procedure Form: Extended Detention Basin (EDB) - Sedimentation Facility Sheet 3 of 3 Designer: MM Company: Interwest Consulting Group Date: December 6, 2013 Project: MVG - Morningstar Facility Location: DETENTION BASIN A (SW) 6. Two -Stage Design - See Figure EDB-1 A) Top Stage (Depth Dwo = 2' Minimum) Dwo = feet - - Top Stage Storage: no less than 99.5% of Design Volume (0.0215,acre-feet.)_ Storage= acre-feet B) Bottom Stage Depth (Des = 0.33' Minimum Below Trickle Channel Invert) Des = feet Bottom Stage Storage: no less than 0.50% of Design Volume (0.0001 acre-feet.) Storage= acre-feet Storage = A " Depth Above W S To Bottom Of Top Stage Surf. Area= acres C) Micro Pool (Minimum Depth = the Larger of Depth= feet 0.50 " Top Stage Depth or 2.5 Feet)j D) Total Volume: Volga = Storage from 5A + 6A + 6B Vol'o' = acre-feet -. '-- (Must be > Design Volume in 1 D, or 0.0216 acre-feet.) 7. Basin Side Slopes (Z, horizontal distance per unit vertical) Z = (horizontaUvertical) Minimum Z = 4, Flatter Preferred 8. Dam Embankment Side Slopes (Z, horizontal distance) Z = (horizontaUvertical) per unit vertical) Minimum Z = 3, Flatter Preferred 9. Vegetation (Check the method or describe "Other") Native Grass Irrigated Turf Grass Other: Notes: . ' UD-BMP_v2.06.xls, EDB - SW POND 12/6/2013, 10:28 AM Design Procedure Form: Extended Detention Basin (EDB) - Sedimentation Facility Sheet 1 of 3 Designer: MM Company: Interwest Consulting Group Date: December 6, 2013 Project: MVG - Morningstar Facility Location: DETENTION BASIN B (NW) 1. Basin Storage Volume la = 47.00 A) Tributary Area's Imperviousness Ratio (i = la / 100) i = 0.47 B) Contributing Watershed Area (Area) Area = 3.180 acres C) Water Quality Capture Volume (WQCV) WQCV =. 0.20 watershed inches (WQCV =1.0'(0.91'13-1.19'I2+0.78.0) D) Design Volume: Vol = (WQCV / 12) ' Area' 1.2 Vol = 0.0630 acre-feet 2. Outlet Works A) Outlet Type (Check One) x Orifice Plate Perforated Riser Pipe Other: B) Depth at Outlet Above Lowest Perforation (H) H = 1.95 feet C) Recommended Maximum Outlet Area per Row, (Ao) Ao = 0.2 square inches D) Perforation Dimensions: i) Circular Perforation Diameter or D = 0.500 inches ii) Width of 2" High Rectangular Perforations W = inches E) Number of Columns (nc, See Table 6a-1 For Maximum) nc ='. 1 number F) Actual Design Outlet Area per Row (Ao) Ao = 0.2 square inches G) Number of Rows (nr) nr = 6 number H) Total Outlet Area (A.0 Ao, = 1.2 square inches 3. Trash Rack A) Needed Open Area: A, = 0.5' (Figure 7 Value) ' Ao, A, = 42 square inches B) Type of Outlet Opening (Check One) x < 2" Diameter Round 2" High Rectangular Other: C) For 2", or Smaller, Round Opening (Ref.: Figure 6a): i) Width of Trash Rack and Concrete Opening (W..) from Table 6a-1 ,... W.m = 3 inches ii) Height of Trash Rack Screen (HTR) HTR = 54 inches UD-BMP_v2.06.xls, EDB - NW POND 12/6/2013, 10:29 AM 1 Design Procedure Form: Extended Detention Basin (EDB) - Sedimentation Facility 11 Sheet 2 of 3 Designer: MM Company: Interwest Consulting Groul Date: December 6, 2013 Project: MVG - Morningstar Facility Location: DETENTION BASIN B (NW) iii) Type of Screen (Based on Depth H), Describe if "Other" S.S. #93 VEE Wire (US Filter) Other: iv) Screen Opening Slot Dimension, Describe if "Other" 0.139" US Filter Other: v) Spacing of Support Rod (O.C.) Type and Size of Support Rod (Ref.: Table 6a-2) vi) Type and Size of Holding Frame (Ref.: Table 6a-2) inches D) For 2" High Rectangular Opening (Refer to Figure 61b): 1) Width of Rectangular Opening (W) W = inches ii) Width of Perforated Plate Opening (W.. = W + 12") W.z = inches iii) Width of Trashrack Opening (W,o„ .) from Table 6b-1 W,o,, v. = inches iv) Height of Trash Rack Screen (Hm) Hm = inches v) Type of Screen (based on depth H) (Describe if "Other") Klempn' KPP Series Aluminum Other: vi) Cross -bar Spacing (Based on Table 6b-1, Klempn KPP I inches Grating). Describe if "Other" Other: vii) Minimum Bearing Bar Size (KlempT"' Series, Table 6b-2) Based on depth of WOCV surcharge) 4. Detention Basin length to width ratio (UW) 5 Pre -sedimentation Forebay Basin - Enter design values A) Volume (3%, to 5% of Design Volume from 1 D) acre-feet (3% - 5% of Design Volume (0.0019 -. 0.0032 acre-feet)...:_ B) Surface Area acres C) Connector Pipe Diameter inches (Size to drain this volume in 5-minutes under inlet control) D) Paved/Hard Bottom and Sides yes/no UD-BMP_v2.06.xls, EDB - NW POND 12/6/2013, 10:29 AM 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Design Procedure Form: Extended Detention Basin (EDB) - Sedimentation Facility II Sheet 3 of 3 Designer: MM Company: Interwest Consulting Group Date: December 6, 2013 Project: MVG - Morningstar Facility Location: DETENTION BASIN B (NW) 6. Two -Stage Design - See Figure EDB-1 A) Top Stage (Depth Dwo = 2' Minimum) Dwo = feet ;Top Stage Storage: no less than,99.5%of Design Volume '.(0.0627 acre' -feet.) - Storage= acre-feet B) Bottom Stage Depth (Dos = 0.33' Minimum Below Trickle Channel Invert) DBS = feet Bottom Stage Storage: 'no less than 0.50% 03 of Design Volume (0.00acre-feet.) Storage= acre-feet Storage = A' Depth Above WS To Bottom Of Top Stage Surf. Area=, acres C) Micro Pool (Minimum Depth = the Larger of Depth= feet '.0.50' Top Stage Depth or 2.5 Feet) -. - D) Total Volume: Vol,,, = Storage from 5A + 6A + 6B Volvo, = acre-feet (Must be > Design Volume in 1 D, or 0.063 acre-feet.) 7. Basin Side Slopes (Z, horizontal distance per unit vertical) Z = (horizontal/vertical) Minimum Z = 4, Flatter Preferred B. Dam Embankment Side Slopes (Z, horizontal distance) Z = (horizontal/vertical) per unit vertical) Minimum Z = 3, Flatter Preferred 9. Vegetation (Check the method or describe "Other") Native Grass Irrigated Turf Grass Other: UD-BMP_v2.06.xls, EDB - NW POND 12/6/2013, 10:29 AM T_2 Grass Swale RESIDUAL CAPACITY FOR LARGER FLOODS 2—YR 4" (MIN) SANDY LOAM I v 1' MIN 12" MIN BOTTOM WIDTH M RESIDUAL CAPACTY FOR � `�Y' � tARCER FLOODS �� 2—YR WSE ,� a �74 MIN. 6' MIN - .. 4' MIN. SANDY LOAM 1 1' MIN. D (2-YR) 1.0 FPS 12' N TRIANGULAR SWALE SECTION NTS CONCRETE COLLAR i i r ENERGY PROVIDE DOUBLE CLEANOUTS WITH WATER TIGHT CAPS 0150' O.C. USE 90' SWEEP OR (2) 45 BENDS (OFFSET FROM SWALE CENTERLINE TO AVOID IMPEDING FLOW WHEN USING A TRIANGULAR SECTION GRADE CONTROL STRUCTURE 4 MIN. GRADE CONTROL STRUCTURE BEYOND GRADE CONTROL STRUCTURE BEYOND O UNDERDRAIN AND SANDY LOAM RECOMMENDED FOR LONGITUDINAL SLOPES < 2.0%. 4" SLOTTED PIPE MEETING TABLE GS-3 WITH CDOT CLASS C FILTER MATERIAL ALL AROUND OR PERFORATED HDPE PIPE WITH AASHTO 167 ALL AROUND CONTAINED WITHIN GEOTEXTILE FABRIC. ASTM D4751—AOS US STD. SIEVE f50 TO #70. ASTM D4533 MIN. TRAPEZOIDAL TEAR STRENGTH 100 X 60 LBS, MINIMUM COE SPECIFIED OPEN AREA OF 49. EXTEND GRADE CONTROL STRUCTURES INTO THE BANK A MIN. 0.5' ABOVE THE 2—YR WSE ENSURE ACCESS TO OUTLET BY CLEAN OUT OR OTHER ACCESSIBLE STRUCTURE SWALE PROFILE NTS Figure GS-1. Grass Swale Profile and Sections Design Example The UD-BMP workbook, designed as a tool for both designer and reviewing agency is available at www.udfcd.ore. This section provides a completed design form from this workbook as an example. GS-6 Urban Drainage and Flood Control District November 2010 Urban Storm Drainage Criteria Manual Volume 3 Extended Detention Basin ( T-5 FLOW LENGTH Z2W ACCESSIBLE OUTLET ���� WITH TRASH RACK 01 4:1 SIDFSLOPES WITH NO AREAS GREATER THAN 3:1. FOR AESTHETIC •4, VARY SLOPES AND DESIGN SHE OIL RIPRAP (WHEN . i'' DE MILDER THAN THE OTHER. ON SIDE ONE DOWNSTREAM GRADE D IS LOWER THAN TOP MICROPOOL t= OF BERM) ' ® CONCRETE / ROCWITH O GROUTED ROCK FLOOR. PROVIDE GROUTED ENERGY OSSSIPATION FOR CONCENTRAlEO FLOW. \O SP14K'AY tl Q N THE BOTTOM OF THE BASIN �`f (, / PRO. IDE A 3% MIN. SLOPE TO THE IC LE CHANNEL ORMICR • /// / F? 0 O 4 �O �--TRICKLE CHANNEL. FOR CONCRETE. SLOPE BETWEEN 0.4.AND I= 3:1 MAX. (BERM) OR VERTICAL CONC. PAN WALL L NTS INITIAL SURCHARGE EMBANKMENT WITH SURFACE PROVIDE DEPTH! 4' MIN., SPILLWAY NERGY INFLOW � IF� EI CONIC. D BERM OR DEPTH DISSIPATION 2.3' MIN, INFLOW ARMORED BERM OR VERTICALWALL CONCRETE OR GROUTED BOULDER/ FOREBAY J 8- MIN. PIPE WITH BERM. USE NOTCH FOR WALL 'SOFT BOTTOM WHERE BASE FLOWS OR GROUNDWATER IS ANTICIPATED 'INCREASE WHERE BASE FLOWS ARE ANTICIPATED �— INVERT OF — E TRICKLE CHANNEL CONCRETE TRICKLE CHANNEL RUNDOWN CONCRETE OR SOFT BOTTOM' MICROPOOL OUTLET WORK (SEE ADDITIONAL DETAILS PR FI IN FACT SHEET 7-12) NTS SEEPAGE CUTOFF COLLAR OF NECESSARY) Figure EDB-3. Extended Detention Basin (EDB) Plan and Profile Additional Details are provided in BW Fact Sheet T-12. This iikhides outlet structure details including orifice plates and trash racks. December 2010 Urban Drainage and Flood Control District EDB-11 Urban Storm Drainage Criteria Manual Volume 3 T-10 Permeable Pavement PERMEABLE PAVEMENT AND� LEVELING COURSE (IF APPLICABLE) 60 MIN. DEPTH DEPENDANT RESERVOIR r r r• e.• r r r s r r r r s r r r r Y r r• 0� r r r'r • r• �' r�rr:rr'...... rr.rs------ rrfrrtrr�i�rgr L• ♦ rti.• • • •'Y ♦ • r°"t ti-r � r * � r r r is r �i y� � r fir. GEOMEM RiANE LINER ¢ r CONNECTION TO m e FILTER MATERIAL CONCRETE. MEETING TABLE PPS-1 (SEE DETAIL PPS-4)' 12* SEPARATOR FABRIC UNDERDRAIN MEETING TABLE PPS-2 30 MIL (MIN.) SEPARATOR FABRIC (ONLY r ENSURE INSTALLATION IS CONSISTENT GEOME'MBRANE WHEN SUBGRADE CONTAINS WITH MANUFACTURER RECOMMENDATIONS LINER PER TABLE PP$-4 ANGULAR ROCK OR OTHER T MAPUNM NO -INFILTRATION SECTION TH EMI E LINER� PERMEABLE PAVEMENT AND 6" MIN_ LEVELING COURSE (IF APPLICABLE) DEPTH DEPENDANT ON TYPE PERIMETER BARRIER 6' MIN. RESERVOIR — (IF APPLICABLE) (AASHTO #57 OR #67) \ I NI -FILTER MATERIAL MEETING TABLE PPS-1 OR SEPARATOR FABRIC IF NEEDED FOR MATERIAL COMPAMBILTTY. TO BE DETERMINED BY A GEOTECHNICAL ENGINEER FULL INFILTRATION SECTION Figure PPS-1- Permeable Pavement Sections PPS-6 Urban Drainage and Flood Control District August 2013 Urban Storm Drainage Criteria Manual Volume 3 T-10 Permeable Pavement Systems H a" SOLID PIPE STORM MANHOLE Y . A OR VAULT {tire.) M-ZTO OUTLET n� ■ i i � • ■ G PLAN VIEW . NTS PLACE LARGER .ROCK (AASHTO /3) TO TO OVERFLOW TO B CONFUJE RESERVOIR MATERIAL Nff .'� \y RISER SUPORTED WITH METAL STRAPS ANCHORED TO WALL UNDERDRAIN FLOW--f FROM CELL TO LOWER CELL ICRETE BOTTOM EO SUBGRADE i SLOTTED PVC MEETING TABLE PPS-2 CONCRETE EDGE {WHERE APPLICABLE) PROVIDE OVERFLOW FROM RESERVOIR ((TOP i' OF RESERVOIR LAYER) TO, AVOID BACNWASHING PAVEMENT TOP OF RISER ELEVATION SET AT WOCV AND NO HIGHER THAN I* BELOW THE TOP OF THE RESERVOIR LAYER ro 6RAIN_THE OF THE WOCV EACH CELL IN y�y+yy,•»yy>.vr OR MORE PT47i*769"^ Figure PPS-7. Underdrain System Layout and Outlet Details PPS-18 Urban Drainage and Flood Control District August 2013 Urban Stonn Drainage Criteria Manual Volume 3 Permeable Pavement Systems T-10 PERMEABLE PAVEMENT BASE COURSE FILTER LAYER SUBGRADE CAST IRON VALVE BOX WITH LOCKING LID REMOVABLE PVC THREADED PLUG & COUPLER 3' MIN. THICK CONCRETE COLLAR CONCRETE EDGE RESTRAINT (IF APPLICABLE) SECTION Figure PPS-$. Observation Well 4"0 SLOTTED PVC PIPE MEETING TABLE PPS-2 (TERMINATE PIPE AT THE BOTTOM OF THE FILTER LAYER WITH A NO INFILTRATION SECTION) August 2013 Urban Drainage and Flood Control District , PPS-19 Urban Storm Drainage Criteria Manual Volume 3