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HomeMy WebLinkAboutLIND PROPERTY - PDP - 39-94B - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTVIII. REFERENCES 1. Storm Drainage Design Criteria and Construction Standards by the City of Fort Collins, Colorado, May 1984, interim revision January 1997. 2. Erosion Control Reference Manual for Construction Sites by the City of Fort Collins, Colorado, January 1991. 3. City of Fort Collins Master Drainage Plan, by XXX Inc, Colorado, 19XX 4. U.S. Department of Agriculture, Soil Conservation Service and Cooperating Agencies. 5. The Urban Storm Drainage Criteria Manual (published by the Urban Drainage and Flood Control District — Denver, Colorado — June 2001). 17 ® VII. CONCLUSIONS 1 A. Compliance with Standards All computations that have been completed within this report are in compliance with the City of Fort Collins Erosion Control Reference Manual for Construction Sites and the Storm Drainage Design Criteria Manual. B. Drainage Concept The proposed drainage concepts presented in this report and on the construction plans adequately provide for the conveyance of developed on -site runoff to the proposed drainage facilities of the subject site. The combination of the proposed curb and gutter, cross -pans, inlets, and storm pipes will provide for the 2-year and the 100-year developed flows to reach the proposed detention pond at the southeast corner of the site. If, at the time of construction, groundwater is encountered, a Colorado Department of _ Health Construction Dewatering Permit will be required. C. Stormwater Quality Concept ' The proposed design has addressed the water quality aspect of stormwater runoff. The grass -lined detention pond will provide an opportunity for stormwater pollutants to filter out of the stormwater runoff before the runoff enters the Old Town Drainage Basin. D. Erosion Control Concept The proposed erosion control concepts adequately provide for the control of wind and rainfall erosion from the Lind Property, Phase I development. Through the construction of the proposed erosion control concepts, the City of Fort Collins performance standard shall be met. The proposed erosion control concepts presented in this report and shown on the erosion control plan are in compliance with the City of Fort Collins Erosion Control Criteria. 16 The Erosion Control Plan along with the Performance Standard and Effectiveness calculations may be found in Appendix J. An erosion control escrow cost estimate of $138,826 is also included in the Erosion Control section of Appendix J. B. Specific Details ° C. Specific Details All disturbed areas not in a roadway or greenbelt area shall have temporary vegetation seed applied within 30 days of initial disturbance. After seeding, a hay or i straw mulch shall be applied over the seed at a rate of 1.5 tons/acre minimum, and the mulch shall be adequately anchored, tacked, or crimped into the soil. Those roads that are to be paved as part of Lind Property, Phase I, must have a 1-inch layer of 1 gravel mulch applied at a rate of at least 135 tons/acre immediately after overlot grading is completed. The pavement structure shall be applied within 30 days after the utilities have been installed. D D I 11 If the disturbed areas will not be built on within one growing season, a permanent seed shall be applied. After seeding, a hay or straw mulch shall be applied over the seed at a minimum rate of 1.5 tons/acre, and the mulch shall be adequately anchored, tacked or crimped into the soil. In the event a portion of the roadway pavement surface and utilities will not be constructed for an extended period of time after overlot grading, a temporary vegetation seed and mulch shall also be applied to the roadway areas as discussed above. All construction activities must also comply with the State of Colorado permitting process for Stormwater Discharges Associated with Construction Activity. A Colorado Department of Health NPDES permit will be obtained so that construction grading can continue within this development. 15 n i VI. F P 0 detain the 100-year runoff + WQCV WQCV Outlet Invert Elevation Top of Pond Bank Elevation Spillway Elevation Please refer to Appendices B and D for calculations. EROSION CONTROL A. General Concept 5012.25 ft 5021.00 ft 5020.00 ft This development lies within the Moderate Rainfall Erodibility Zone and the Moderate Wind Erodibility Zone per the City of Fort Collins zone maps. There should be minimal to no erosion problems after completion of Lind Property, Phase I, development. Silt fence will be installed along the west and south sides of the site to prevent sediment from leaving the site. Tracking pads will also be placed at entrances/exits to the site. The Rainfall Performance Standards for Phase I, during and after construction, were calculated to be 81.0 and 95.3 respectively. Therefore the erosion control plan shall be developed to contain 81.0% and 95.3% of the rainfall sediment that would normally flow off a bare ground site during a 10-year rainfall event during and after construction respectively. The Effectiveness values for the site during and after construction were calculated to be 95.2 and 97.6 respectively. These values demonstrate that the developed Erosion Control Plan contains at least the minimum amount of rainfall sediment on -site required during and after construction, therefore, the erosion control plan below meets the City of Fort Collins requirements. Performance Standard During Construction 81.0 Performance Standard After Construction 95.3 Effectiveness During Construction 95.2 Effectiveness After Construction 97.6 14 ® V. STORMWATER QUALITY A. General Concept The water quality of stormwater runoff must be addressed on all final design utility plans. Therefore, we have sought to find various Best Management Practices for the treatment of stormwater runoff. Lind Property, Phase I, will be providing a grass lined detention pond (on -site). This water quality feature will provide a mechanism for pollutants to settle out of the stormwater runoff before flows are directed to the Cooper Slough Drainage Basin. IB. Specific Details Both retention and detention facilities will have adequate capacity to provide water quality capture volume before being released. The ponds will have adequate volume between the spillway elevation and the water quality control volume elevation to detain the developed 100-year storm. If the outlet structure should ever become plugged, in the detention pond, the pond's spillway has been designed to prevent the pond from overtopping by providing a controlled release while maintaining one foot of freeboard. Side slopes of 4:1 were utilized throughout the both ponds. The following table summarizes the calculated storm water runoff quantities in both the retention pond and then the detention pond design parameters: Retention Pond — Lind Property, Phase I Drainage Basin Area 44.93 acres Pond Volume Required 21.36 ac-ft Pond Volume Provided 21.77 ac-ft Top of Pond Bank Elevation 5021.00 ft Spillway Elevation 5020.00 ft Detention Pond — Lind Property, Phase I and Future Phases Drainage Basin Area 85.89 acres Existing 2-year Runoff 17.26 cfs Pond Volume Required to 18.52 ac-ft detain the 100-year runoff WQCV Required 1.763 ac-ft Pond Volume Required to 20.28 ac-ft detain the 100-year runoff + WQCV Pond Volume Provided to 21.77 ac-ft 13 continue east down CR52 where it will eventually be captured in a 15' Type R curb inlet (in sump). ® SUB -BASIN F12 The stone water from sub -basin F12 (Qloo = 6.17cfs) will be routed in the curb -gutter and cross -pans along the north side of CR52 where it will be captured in a 15' Type R curb inlet (in sump). SUB -BASIN F13 The storm water from sub -basin F13 (Qloo = 15.55cfs) will be routed in the curb - gutter and cross -pans along the south side of CR52 where it will be captured in a 10' Type R curb inlet (in sump). SUB -BASIN F14 The storm water from sub -basin F14 (Qtoo = 6.15cfs) will be routed in the curb -gutter and cross -pans along the south side of CR52 where it will be captured in a 10' Type R curb inlet (in sump). SUB -BASINS F69 F79 F81 F9 Flows from sub basin F6 (Qtoo = 27.07cfs), sub basin F7 (Qioo = 35.06cfs), sub basin F8 (Qtoo = 37.23cfs) and sub basin F9 (Qloo = 59.18cfs) will flow to future inlets located off Phase I. These flows will eventually flow onsite and into the proposed retention/detention pond at the southeast corner of the Phase I. Until future phases of Lind property are constructed, the flows from these basins will travel via overland flow to an existing storm culvert at the southeast comer of the site. SUB -BASIN OS1 The storm water from sub basin OS 1 (Qioo = 4.78cfs) will travel down the west side of CR 11 undetained. The existing flows from this basin do not run through the site. C. Street Capacity The street capacities for the streets inside the Lind Property were calculated using the Rational Method, as seen in Appendix C. The proposed street design meets the required 2-year and 100-year street capacities. C I 9 12 " 20 (Qioo = 3.08cfs). The combined flow from sub basin F5 and 20 will continue down the north side of Brightwater Drive where it will eventually eventually be captured in a 15' combination inlet (in sump) Until future phases of Lind property are constructed, the flow from basin F5 will itravel via overland flow to an existing storm culvert at the southeast corner of the site. SUB -BASINS 19, Fl, F3 Flows from sub basin 19 (Qioo = 0.70cfs), sub basin F1 (Qtoo = 41.35cfs) and sub basin F3 (Qioo = 4.65cfs) will flow to future inlets located off Phase I. These flows will eventually combine with the flows onsite and into the proposed retention/detention pond at the southeast corner of the site. Until future phases of Lind property are constructed, the flows from basin F1 and F3 will travel via overland flow to an existing storm culvert at the southeast corner of the site. SUB -BASINS 19, Fl, F3 Flows from sub basin 19 (Q100 = 0.70cfs), sub basin F1 (Qioo = 41.35cfs) and sub basin F3 (Qioo = 4.65cfs) will flow to future inlets located off Phase I. These flows will eventually combine with the flows onsite and into the proposed retention/detention pond at the southeast corner of the site. Until future phases of Lind property are constructed, the flows from basin F1 and F3 will travel via overland flow to an existing storm culvert at the southeast corner of the site. SUB -BASINS 21 and F11 Flows from sub basin 21 (Qioo = 2.49cfs) and sub basin F11 (Qloo = 22•46cfs) will flow to future inlets located off Phase I. These flows will combine with flows from future phases and will be detained in future detention ponds within Lind Property. Until future phases of Lind property are constructed, the flow from basin F11 will travel via overland flow to an existing storm culvert at the southeast comer of the site. SUB -BASINS 29 23, 259 26, 289 F12 The flow from sub basin 25 (Qioo = 7.54cfs) will travel via curb -gutter and cross -pans along the east of CR11 to CR52 where it will eventually meet up with the flows from sub basin F26 (Qioo = 14.64cfs). Meanwhile, the flow from sub basin 23 (Qloo = 3.48cfs) will travel via curb -gutter and cross -pans along the east side of Bar Harbor Drive where it will eventually combine with the flows from sub basin 28 (Qloo = 2.79cfs). The combined flows from sub basins 23 and 28 will continue along Bar Harbor Drive until CR52. At CR52, the combined flow from sub basins 23 and 28 will meet up with the flows from sub basin 2 and the combined flow of sub basins 25 and 26. These flows will 1 11 'r SUB -BASINS 11 and 13 The storm water from sub -basin 11 (Qloo = 23.59cfs) will be routed in the curb -gutter and cross -pans along the north side of Sternwheeler Drive and the west of Forecastle Drive to design point 11. At this point the flows from sub basin 11 will combine with the flows from sub basin 13 (Qloo = 8.84cfs). The combined flow will continue along the north side of Sternwheeler Drive to a 10' combination inlet (in sump). SUB -BASIN 157 16, 17 The storm water from sub basin 17 (Qloo = 2.59cfs) will be routed in the curb -gutter and cross -pans along the south side of Brightwater Drive. Flows from sub basin 16 (Qioo = 4.03cfs) will be routed via curb -gutter and cross -pans along the west of Barharbor Drive and east of Port place drive to Clipperway. The storm water from sub basin 15 (Qioo=12.09cfs) will be routed in the curb -gutter and cross -pans along the east side of Port lace Drive. These flows will meet up along Clipper Way where they will combine in a 10' combination inlet. SUB -BASIN 12,149 24 The storm water from sub basin 24 (Qloo = 6.62cfs) will travel via curb -gutter and cross -pans to along the east side of County Road 11 to Brightwater Drive where it will combine with the flows from sub -basin 12 (Qioo = 5.30cfs). The combined flow from sub basin 24 and 12 will continue down the south side of Brightwater Drive where it will eventually meet up wit the flows from sub -basin 14 0100 = 6.55cfs); The flows from sub basins 24, 12 and 14 will continue along Brightwater where it will eventually be captured in a 10' Type R curb inlet (in sump) SUB -BASIN F2,18, F101 F4 The storm water from sub basin F2 (Qloo = 4.57cfs) will travel down the east side of CRl 1 to Brightwater Drive where it will combine with the flows from sub basin 18 (Qloo = 18.92cfs). Meanwhile the storm water from sub basin F10 (Qjoo = 7.06cfs) will travel down the west Fairwater Drive to Brightwater Drive where it will combine with the flows from sub basin F2 and 18. The combined flows from sub basin F2,18 and F10 will continue along Brightwater where it will eventually meet up with the flows from sub basin F4 (Qloo = 12.02cfs). The combined flows from these basins will continue along Brightwater Drive until they are eventually captured in a 15' combination inlet (in sump). Until future phases of Lind property are constructed, the flows from basins F2 and F10 will travel via overland flow to an existing storm culvert at the southeast comer of the site. 1 SUB -BASIN F5, 20 The storm water from sub basin F5 (Qloo = 32.24cfs) will travel via curb -gutter and cross -pans to Brightwater Drive where it will combine with the flows from sub -basin 10 SUB -BASINS 1, 39 5 ti The storm water from sub -basin 1 (Q100 =14.98cfs) will be routed in the curb -gutter ® and cross -pans along the south side of Mainsail Drive and the west side of Forecastle Drive to sub -basin 5 (Qiob = 24.80 cfs). At this point the combined flows from sub basin 1 and 5 travel via curb and gutter to Mainsail drive to Flagstaff Drive/Place ® where it will eventually combine with flows from sub basins 3 (Qloo = 20.34cfs). the combined flows from basins 1,3,5 will eventually be captured in a 15' combination Ei inlet (in sump). SUB -BASINS 49 69 7 The storm water from sub -basin 4 (Q10o = 4.57cfs) will be routed in the curb -gutter and cross -pans along the south side of Bowspirit Drive to design point 4 where it will combine with flows from sub basin 6 (Qloo =19.45cfs). At this point the combined ® flows will travel down the west side of Port Place Drive where it will eventually combine with part of the flow from sub basin 7. This combined flow will continue down the street to design point 7 where it will be collected in a 10' combination inlet (in sump). Meanwhile some of the flows form sub basin 7 will be routed in the curb -gutter and cross -pans along the east side of Bar Harbor Drive. The flows from sub basin 7 will eventually be collected in a 10' combination inlet where it will join with the flows from basins 4, 6 and the rest of the flow form sub basin 7. e SUB -BASIN 27 ® The storm water from sub -basin 27 (Qloo = 2.23cfs) will be routed in the curb -gutter and cross -pans along the south side of Bowspirit Drive where it will be captured in a 5' Type R curb inlet (in sump). SUB -BASINS 8 and 9 The storm water from sub -basin 8 (Qioo = 25.05cfs) will be routed in the curb -gutter and cross -pans along the north side of Bowsprit Drive and the west of Fairwater Drive to design point 8. At this point the flows from sub basin 8 will combine with the flows from sub basin 9 (Qloo=18.79cfs). The combined flow will continue along the north side of Bowsprit Drive to a 10' combination inlet (in sump). SUB -BASIN 10 The storm water from sub -basin 10 (Qloo = 7.90cfs) will be routed in the curb -gutter _ and cross -pans along the south side of Clipper -way where it will be captured in a 5' ® Type R curb inlet (in sump). 0 9 The City of Fort Collins is currently preparing a Master Plan Update for stormwater. The Lind Property detention pond cannot outlet into the existing storm drain sysytem, so the pond will be designed as a retention facility. Due to this, only the storm water created by the Lind Property development, Phase I, will be captured in the retention pond, all other flow will travel as historically done. Historically Lind Property travels via overland flow to the southeast corner of the site where it is captured in two 12" CMP drainage culverts. These culverts direct the flow under County Road 52 to the property to the south of the subject site. At this point the water is released onto the southern property via overland flow. Until the future phases of Lind Property are developed this water will continue through the undeveloped portions of the site, to the culvert, and onto the southern property as historically traveled. The on -site flows will be captured in the detention pond located on Phase I. The rest of the flows will pass through, un-detained, to the existing culvert. The existing storm drain is a relatively flat 15" cmp pipe. This pipe can only hold approximately 2cfs of storm water runoff. This storm drain will be upgraded to a 24"rcp pipe, so as to maintain the 2-year minor year storm flow of approximately 17.26cfs. This drain will run under CR52 and release the flow onto the property to the south. In the event of a storm larger than the 2-year storm should occur, the City of Fort Collins has agreed to allow the storm water to pass over CR52, as long as the flow does not reach more than half a foot above the crown of the road. In the future, the City of Fort Collins will allow the Lind Property development to tie into the existing storm drain along CR52. The existing storm drain runs along the south side of CR52 where it eventually ends at the Reservoir No. 8 Outlet Canal. The pond at the southeast comer of the Lind Property, Phase I, site will release into a proposed 24" storm drain. This drain will carry the water underneath CR52 where it will eventually tie into the existing storm drain just before the water is released into the canal. At this point the existing storm drain will be upgraded to a 36" reinforced concrete pipe that will be able to handle the flow from the existing drain as well as the flow from the detention pond on Lind Property. I B. Specific Details The Lind Property, Phase I, site has been broken down into twenty-nine sub -basins. The attributed runoff from the majority of the basins is routed to the on -site retention pond located at the southeast comer of Phase I. I 0 I I iB. Development Criteria Reference and Constraints The criteria and constraints from the City of Fort Collins will be met. C. Hydrologic Criteria The Rational Method for determining surface runoff was used for the project site. The 2-year and 100-year storm event intensities were used in calculating runoff ® values. The City of Fort Collins intensity duration frequency curves were used to obtain rainfall data for each storm specified. Since Phase I of Lind Property is less ® than 160-acres, the Rational Method was used to calculate historic and developed stormwater runoff. The detention pond sizing was computed using the FAA method from the Urban Storm Drainage Criteria computer software program. The water quality for the pond was computed using the Water Quality Capture Volume equation from the Urban Storm Drainage Criteria Manual, Volume 3. These calculations and criteria are included in Appendices B and D of this report. D. Hydraulic Criteria All hydraulic calculations within this report have been prepared in accordance with the City of Fort Collins Drainage Criteria and are also included in the Appendix. E. Variance ® No variances are being requested for the Lind Property, Phase I, project. IV. DRAINAGE FACILITY DESIGN ® A. General Concept The majority of the runoff produced by the Lind Property, Phase I, development flows via curb and gutter, cross -pans, inlets, and storm pipe to a proposed retention pond located at the southeast corner of Phase I. The off -site developed basins F1 through F 12 were designed from conceptual data of future phases as well as from the upgrade of CR52. The majority of these basins, according to conceptual design, will also flow via curb and gutter, cross -pans, inlets, and storm pipe to the proposed pond in Phase I. The capacity of the pond, along with its outlet structure and spillway were designed with the consideration that future phases would be constructed. There currently exists a 24" storm drain system along County Road 52, directly south of the site. This system was constructed with the Richards Lake P.U.D. improvements. 7 Major Basin, A2 (44.5acres), drains southeast at an approximate slope of 1.0 to 2.0 percent. The stormwater from this basin is collected in a second existing 12" CMP culvert and is also released on the property south of the Lind Property site. These basins can be seen in the Drainage Exhibit found in Appendix B. B. Sub -basin Description The area encompassed by the proposed site for Phase I of Lind Property has been divided into twenty-nine sub-basins,1-28, and OS-1. Onsite runoff from basins 1-28 were routed to an on -site retention pond. This retention pond will be located in,the. south east corner of Phase I. Flows from basin OS-1 will continue to flow down the west side of CRl 1. The storm water from this basin will not be collected in the retention pond on site. Three offsite basins, F12-F14, were created based on the development of CR52. The water form these basins will flow onsite via curb -gutter, cross -pans and storm drains to the retention pond located in the southeast corner of the site. Ten offsite sub -basins, F1 through F10, were created based on development of the surrounding area by future Phases of Lind Property. These ten basins are to be routed to a future detention pond on Phase I. These basins were analyzed due to a conceptual layout and grading of the future phases of Lind Property. These sub -basins can be seen in the Drainage Exhibits found in the back of the report. III. DRAINAGE DESIGN CRITERIA A. Regulations Since the Lind Property, Phase I, site is located in the Cooper Slough Drainage Basin in the City of Fort Collins, the criteria is to detain the 100-year developed stormwater runoff and release it at the 2-year historic discharge rate. The Urban Storm Drainage Manual (published by the Urban Drainage and Flood control District — Denver, Colorado) and the City of Fort Collins Storm Drainage Design Criteria, have been used to calculate the stormwater runoff and design the storm water facilities for this site. At this time, stormwater released from the detention pond is not allowed due to the Master Plan Update not being complete. 3 i PROJECT DEVELOPMENT PLAN DRAINAGE AND EROSION CONTROL STUDY FOR LIND PROPERTY PHASE I FORT COLLINS, COLORADO I. GENERAL LOCATION AND DESCRIPTION A. Location Lind Property is bounded to the north and east by the Reservoir No. 8 Outlet Canal, to the south by County Road 52, and to the west by County Road 11. The property to the north, south and west of the site is agricultural land, and Richard's Lake r Subdivision (rural homes) makes up the property to the west. ® The site location can also be described as situated in the west half of Section 29, Township 8 North, Range 68 West of the 6`h P.M., of the City of Fort Collins, Larimer County, Colorado, and comprises approximately 173 acres (see vicinity map Appendix A). Phase I is approximately 45 acres, located in the southwest comer of the site. B. Description of Property The Lind Property, Phase I, consists of approximately 185 single family units and approximately 45 acres of land, which is currently fallow agricultural land. The topography of Phase I generally slopes northwest to southeast (towards County Road 52 and the no 8 ditch.) at varying slopes from 1.0 percent to 5.0 percent. II. DRAINAGE BASINS A. Major Basin Description The Lind Property development lies within the Cooper Slough Drainage Basin. The Cooper Slough Drainage Basin generally flows north to south and ultimately drains into the Larimer and Weld County Canal. There are two major drainage basins that contribute to the existing storm runoff that travels through Phase I of the Lind Property site. Major Basin, Al (66.3acres), drains southeast at an approximate slope of 3.0 to 5.0 percent. The stormwater from this basin collects in an existing 12" CMP culvert, is routed under County Road 52, and is released via overland flow onto the adjacent land south of Lind Property. 5 I APPENDICES VICINITY MAP CITY OF FORT COLLINS STORMWATER BASINS A RATIONAL METHOD HYDROLOGY B STREET CAPACITY CALCULATIONS C DEI:ENTION/RETENTION POND SIZING D INLET SIZING -- UDINLET E STORM SEWER PIPE SIZING -- UDSEWER F RIPRAP DESIGN EROSION CONTROL: PERFOMANCE STANDARDS, G EFFECTIVENESS, CONSTRUCTION SEQUENCE, COST ESTIMATE SOIL TYPE H DRAINAGE AND EROSION CONTROL PLAN DRAWINGS AND DETAILS I iv TABLE OF CONTENTS DESCRIPTION PAGE I. GENERAL LOCATION AND DESCRIPTION 5 A. Location 5 B. Description of Property 5 II. DRAINAGE BASINS 5 A. Major Basin Description 5 B. Sub -basin Description 6 III. DRAINAGE DESIGN CRITERIA 6 A. Regulations 7 B. Development Criteria Reference and Constraints 7 C. Hydrologic Criteria 7 D. Hydraulic Criteria 7 E. Variances from Criteria 7 IV. DRAINAGE FACILITY DESIGN 7 A. General Concept 7 B. Specific Details 8 C. Street Capacity 12 V. STORMWATER QUALITY 12 A. General Concept 13 B. Specific Details 13 VI. EROSION CONTROL 14 A. General Concept 14 B. Specific Details 15 VII. CONCLUSIONS 16 A. Compliance with Standards 16 B. Drainage Concept 16 C. Stormwater Quality Concept 16 D. Erosion Control Concept 16 VIII. REFERENCES 17 APPENDICES iii 1 5__SEAR-B�ROW�N M ® Mr. Basil Hamden City of Fort Collins Water Utilities--Stormwater ® 700 Wood Street Fort Collins, Colorado 80521 ARCHITECTURE 209 South Meldrum EN�aini e.It.rnNe, Fort Collins, CO 80521 111-ANINING 970.482.5922 phone CONSrRtx:rioN 970.482.6368 fax www.searbrown.com October 15, 2002 ® RE: Project Development Plan Drainage and Erosion Control Study for Lind Property, Phase I Dear Basil: ® We are pleased to submit to you, for your review and approval, this Project Development Plan Drainage and Erosion Control Study for the Lind Property, Phase I. All computations within this report have been completed in compliance with the City of Fort Collins Storm Drainage ® Design Criteria. We appreciate your time and consideration in reviewing this submittal. Please call if you have ® any questions. Respectfully, Sear -Brown Prepared by: Reviewed by. tlic1haelsen, �J'acIyn EIT Jim Allen -Morley, P.E. Design Engineer Project Manager cc: File 614-003 Project Development Plan Drainage and T. 1 Erosion Control Study for the -r 1 1 Lind Property 1 Phase I I Fort Collins, Colorado 1 1 I F PC SEAR•BROWN October 15, 2002