Loading...
HomeMy WebLinkAboutDrainage Reports - 11/02/1995r, 0 Final Drainage and Erosion Control Report for PI KAPPA ALPHA FRATERNITY EXPANSION Fort Collins, Colorado Prepared for: Amshel Corporation PO Box 1978 Fort Collins, Colorado 80522 Prepared by: Shear Engineering Corporation Project No: 1060-02-95 Date: October, 1995 4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282-031 1 October 24, 1995 Project No: 1060-02-95 Basil Hamdan City of Fort Collins Stormwater Utility P.O. Box 580 Ft. Collins, Colorado 80522 Re: PI KAPPA ALPHA FRATERNITY EXPANSION; Fort Collins, Colorado Dear Basil, Enclosed, please find the Final Drainage and Erosion Control Report for the PI KAPPA ALPHA FRATERNITY EXPANSION. The hydrology data and the hydraulic analysis presented in this report complies with the requirements of the City of Fort Collins Storm Drainage Criteria Manual; dated March, 1984, and the Erosion Control Reference Manual. The plans and report have been revised per your comments dated October 23, 1995. Your original redlined report and plan are attached for your convenience. Per our phone conversation of Monday October 23, 1995, I have also enclosed mylars for your signature. We will follow up with sepias and signed and stamped prints after we have received approved plans. If you have any questions or comments, please call me or Mark Oberschmidt at 226-5334. E e D YY J / 111GV cc: Amshel Corporation 4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282-0311 Page 1 Final Drainage and Erosion Control Report Project No. 1060-02-95 The Pi Kappa Alpha fraternity currently consists of two (2) fraternity houses and a small gravel based parking area. There is an existing duplex unit located along Meldrum just north of the existing fraternity house at the intersection of Laurel and Meldrum, between the fraternity house and the alley to the north which accesses the fraternity parking area. Development of the site will take place over several years and consists of two phases. The existing parking area will be re -defined based on final parking lot design conditions, and paved as a part of a Phase 1 improvement to the site. Paving will proceed in 1995. The ultimate fraternity expansion plan includes the demolition of the two (2) existing fraternity houses and the duplex located just to the North/Northeast of the existing fraternity houses. A single new fraternity house will be constructed and the parking lot expanded to ultimate design considerations. Ultimate improvements may occur in two years. This report analyzes the overall drainage effect of the ultimate development considering the entire proposed parking lot and the proposed single fraternity house. The present phase 1 parking lot construction will include placement of a portion of the overall designed parking area. Two plans are presented with this report to represent both the initial phase of development and the ultimate development of the site. Page 2 Final Drainage and Erosion Control Report Project No. 1060-02-95 L GENERAL LOCATION AND DESCRIPTION: A. Location 1. The proposed Pi Kappa Alpha fraternity is located in the Southeast quarter of Section 11, T7N, R69W of the 6th P.M., Fort Collins, Colorado. 2. More specifically, it is located at 402-406 West Laurel Street on the Northwest corner of the intersection West Laurel and Meldrum Streets. The project site is located in the southwest section of Old Town Fort Collins. 3. The site is bounded on the south (across the street) by Colorado State University, on the east by single family residential development along West Laurel and Meldrum, on the west by an existing sorority house and on the north by multi -family and single family development. B. Description of Property 1. There are several existing buildings on the 0.71 acre site along with a gravel parking lot. The existing buildings consist of two (2) fraternity houses fronting on West Laurel Street and a duplex which fronts on Meldrum Street. 2. The proposed expansion, will occur in two stages. The first stage will consist of the following; a. Grading and paving the existing graveled parking area to meet partial ultimate parking lot design considerations. The final stage will consist of the following; a. Demolition of the two fraternity houses and the duplex. b. Construction of a larger fraternity house along with the final portion of the parking lot. 3. Two plans are submitted with this report defining the extent of work to be done during the two stages of construction. Page 3 Final Drainage and Erosion Control Report Project No. 1060-02-95 II. DRAINAGE BASINS AND SUB -BASINS: A. Major Basin Description 1. The site is located within the Old Town Basin as defined on the City of Fort Collins Master Stormwater Basin Map. a. The Basin fee rate for this basin is $4,150.00 per gross acre according to the development fee section of the City of Fort Collins Development Manual. It is our understanding that this may be reduced if detention is provided. 2. The flow pattern of this portion of Old Town Basin is generally easterly and northerly to the Cache La Poudre River. It is highly channelized as it is almost completely developed. Street and storm sewer infrastructure are the primary means of stormwater conveyance. 3. There are currently no Master Drainage Improvement plans for this section of the Old Town Basin. 4. There is a concrete lined, underground irrigation ditch which traverses the Northeast corner of the overall site. This underground irrigation ditch represents a design constraint associated with the ultimate development of the Pi Kappa Alpha fraternity site. B. Sub -Basin Description 1. The site is historically defined by two (2) minor sub -basins. From about the center of each of the three existing units, runoff is conveyed to the Laurel and Meldrum street system (front yard drainage). Runoff from the remaining area is conveyed to the rear of the units, to the existing parking area, and to the alley located along the north property line. 2. There is a 24" valley pan located in the center of the alley on the north side of the site. The pan conveys stormwater in a westerly direction to an existing inlet. From the inlet, a 12" diameter PVC storm sewer pipe conveys runoff to the north. 3. Stormwater in Meldrum Street generally flows in the gutter in a northerly direction from the intersection. 4. Stormwater in West Laurel Street generally flows east to an existing inlet located near the intersection of Meldrum and Laurel. A 10" cast iron pipe conveys stormwater from the inlet to the east. Page 4 Final Drainage and Erosion Control Report Project No. 1060702-95 III. DRAINAGE DESIGN CRITERIA: A. Regulations 1. Design Criteria from the City of Fort Collins Storm Drainage Design Criteria Manual and options for storm drainage improvements discussed by the City of Fort Collins were considered. B. Development Criteria Reference and Constraints 1. The site is completely developed on all sides, creating grading constraints for the entire perimeter of the project. 2. Detention is required with this project. The flexibility for achieving the required detention volume in the parking area, is severely limited due to the surrounding constraints, including the three (3) existing buildings on the site which remain as a part of phase 1. a. The parking lot can not be raised for surface outfalls due to the limiting alley grades to the north. b. Parking lot grades and detention outfall, depends entirely on the utilization of the existing inlet Northwest of the site, in the alley. The inlet is shallow (1.80' deep) and further limits the flexibility for achieving the required detention volume in the parking area. c. Detention pond outfalls to either Laurel or Meldrum are extremely difficult to achieve due to the proximity of the parking lot to Laurel and due to the proximity of the underground irrigation ditch along Meldrum. C. Hydrological Criteria 1. The Rainfall -Intensity -Duration curves for the City of Fort Collins were used (Figure 3-1, attached for reference), in conjunction with the "Rational Method" for determining peak flows at various concentration points. 2. The two (2) and one hundred (100) year storms were studied in accordance with Table 3-1 of the City of Fort Collins Storm Drainage Design Criteria Manual for residential sites. 3. Detention pond volumes were determined using the the Mass Diagram Method (Cumulative Runoff Method). The maximum allowable release rate is based on the peak 2 year flow for historic conditions. D. Hydraulic Criteria 1. Storm sewer and drainage channel capacities are based on the Mannings Equation. The Mannings coefficients will be as suggested by the City of Fort Collins Storm Drainage Criteria Manual. Page 5 Final Drainage and Erosion Control Report Project No. 1060-02-95 M. DRAINAGE DESIGN CRITERIA: D. Hydraulic Criteria 2. Detention outfalls are based on the orifice equation utilizing the orifice equation coefficient as suggested by the City of Fort Collins Storm Drainage Criteria Manual. IV. DRAINAGE FACILITY DESIGN: A. General Concept 1. The parking area will be designed to create a detention pond, maximizing storage volumes with the design constraints mentioned. a. The grading design in the parking area will provide detention storage for both the Phase 1 and Ultimate conditions. b. The grading design for the ultimate conditions attempts to maximize the contributing area to the detention pond. 2. A majority of the stormwater runoff from the site, will be conveyed to the parking area detention pond at the time of ultimate development. This will require that the building design consider roof drainage which will allow for conveyance of stormwater to the parking lot from the northern half of the roof. 3. Stormwater from the parking lot detention area will be conveyed to an existing 2' x 2' area inlet located in the alley on the north side of the site. a. A sanitary sewer line located in the alley immediately below the 24" valley pan, limits the flexibility for aligning the detention pond outfall pipe to the existing inlet. Page 6 Final Drainage and Erosion Control Report Project No. 1060-02-95 IV. DRAINAGE FACILITY DESIGN: B. Specific Details 1. A summary of the Phase one detention requirements and design values is listed below. The pond was sized using the entire site area (0.71 acres) in conjunction with the Mass Diagram Method even though only a portion of the site, sub -basin In (= 0.34 acres), actually contributes stormwater to the pond. This was done in order to compensate for the areas which do not contribute to the pond area (Sub -basin lb and Ic). a. The high water surface elevation, prior to overflow into the alley, is 5001.6 feet. b. The required storage volume is 2,756 cubic feet. c. The storage volume provided is 2,992 cubic feet. d. The 100 year Water Surface Elevation (W.S. El.) is approximately 5001.40 feet. e. The maximum pond depth is 1.0 foot. 2. A summary of the ultimate condition detention requirements and design values is listed below. The grading design for the ultimate development of the site increases the onsite contributing area to the pond from 0.34 acres to 0.42 acres. This results in a net decrease in runoff from Sub -basin lb and Ic from the existing condition to the ultimate condition. Refer to page 10 in the drainage calculations. a. The high water surface elevation, prior to overflow into the alley, is 5001.6 feet. b. The required storage volume is 3646 cubic feet. c. The storage volume provided is 3985 cubic feet. d. The 100 year Water Surface Elevation (W.S. El.) is approximately 5001.42 feet. e. The maximum pond depth is 1.0 foot. Page 7 Final Drainage and Erosion Control Report Project No. 1060-02-95 IV. DRAINAGE FACILITY DESIGN: B. Specific Details (continued) 3. The detention pond outfall will consist of an orifice opening in a high curb, located at the low point of the parking lot. A small box structure, similar to a diversion box, will be provided at this point, to allow the main outfall to the existing inlet to consist of a 12" diameter storm sewer. a. The orifice discharge invert elevation is 5000.6 feet. The orifice has a diameter of four (4") inches. b. The top of the outlet structure is at an elevation of 5001.6 feet. c. A four (4') foot wide weir is provided on the east side of the structure at an elevation of 5001.42 in order to insure that the required storage for the 100-year storm event is provided and provide a small overflow device. Refer to page 15 in the drainage calculations. The top of the structure on the other three sides are at an elevation of 5001.6 feet. d. The orifice opening will restrict flows to the historic 2-year flows. The maximum allowable release rate is 0.50 cfs. e. The outfall storm sewer from the diversion box to a manhole in the alley will be a 6" diameter PVC storm sewer at 0.40%. The storm sewer will then tie into the existing inlet just northwest of the project site. This will require reconstruction of damaged 24" valley pan in the alley. The storm sewer from the manhole to the existing area inlet will be a 12" RCP class V pipe at 0.40%. Class V pipe is necessary due to the minimum cover that is provided over the pipe. 4. The outlet pipe from the pond conveys stormwater to an existing area inlet located in the alley on north side of the site. a. The grate elevation of the existing inlet is 5001.1 feet. b. The invert elevation of the inlet is 4999.3 feet. c. The outlet pipe from the existing inlet is a12" PVC. Page 8 Final Drainage and Erosion Control Report Project No. 1060-02-95 V. EROSION CONTROL: A. General Concept 1. Erosion control measures are specified on the Drainage and Erosion Control plan. a. Maintenance of erosion control devices will remain the responsibility of the contractor and the owner until the project is complete. b. Erosion control measures will be required for Phase 1 improvements. Further erosion control measures will be required when ultimate development of the proposed expansion occurs. c. An additional security deposit may be required at the time of ultimate development. B. Specific Details 1. The following measures are specified on the Drainage and Erosion Control plan: a. A gravel inlet filter around the proposed detention pond outfall in the parldng area. This will be required for both Phase 1 and ultimate development construction phases. b. An area inlet filter composed of Hay bales around the existing inlet in the alley. c. An inlet gravel filter will be required for the inlet located at the Northwest corner of the intersection of Laurel and Meldrum. This device will only be required when the ultimate development occurs. d. Silt fence along the Meldrum and Laurel Streets. The silt fence will only be required when the ultimate development occurs. Page 9 Final Drainage and Erosion Control Report Project No. 1060-02-95 VI. EROSION CONTROL SECURITY DEPOSIT: An erosion control security deposit is required in accordance with City of Fort Collins policy (Chapter 7, Section C : SECURITY; page 7.23 of the City of Fort Collins Development Manual). In no instance shall the amount of the security be less than $1000.00. 1. According to current City of Fort Collins policy, the erosion control security deposit is figured based on the larger amount of 1.5 times the estimated cost of installing the approved erosion control measures or 1.5 times the cost to re -vegetate the anticipated area to be disturbed by construction activity. i The cost to install the proposed erosion control measures is approximately $150.00. Refer to the cost estimate attached in Appendix I. 1.5 times the cost to install the erosion control measures is $ 225.00. ii. Based on current data provided by the City of Fort Collins Stormwater Utility, and based on an actual anticipated net affected area which will be disturbed by construction activity (approximately 0.20 acres), we estimate that the cost to re - vegetate the disturbed area will be $260.00 ($1,300.00 per acre x 0.20 acres). 1.5 times the cost to re -vegetate the disturbed area is $390.00. The $1,300.00 per acre for re -seeding sites of less than 1 acre was quoted to us by the City of Fort Collins Stormwater Utility staff. 2. The erosion control security deposit amount required for Phase 1 of the Pi Kappa Alpha Expansion will be $1,000.00. See the Erosion Control Security Deposit Requirements document located in Appendix III. 3. The erosion control security deposit is reimbursable. VIL VARIANCE FROM CITY STANDARDS A. Variance from City of Fort Collins requirements 1. With this report , we are formally requesting a variance from the City of Fort Collins Standard that the minimum pipe size in City R.O.W. be fifteen (15") inches. a. We are using a 12" Class V pipe in the R.O.W. because the inlet we are connecting into is very shallow. b. If a 15" pipe were installed there would be insufficient cover on the pipe. Page 10 Final Drainage and Erosion Control Report Project No. 1060-02-95 VIIL CONCLUSIONS: IX. A. Compliance with Standards 1. All drainage analysis has been performed according to the requirements of the City of Fort Collins Storm Drainage Criteria Manual. 2. Proposed drainage improvements generally conform with the recommendations of the " City of Fort Collins Master Drainage Plan. 3. Proposed erosion control measures generally conform with the recommendations of the City of Fort Collins standards. B. Drainage Concept 1. The proposed drainage design for Pi Kappa Alpha Fraternity is effective for the control of storm runoff with a considerable reduction in potential downstream effects. 2. The proposed drainage design for Pi Kappa Alpha Fraternity will have absolutely no effect on City of Fort Collins Master Drainage Plan recommendations. 1. City of Fort Collins "Storm Drainage Design Criteria and Construction Standards'; May, 1984 2. City of Fort Collins "Erosion Control Reference Manual"; January, 1991 FLOW SUMMARY FOR PI KAPPA ALPHA FRATERNITY EXPANSION EXISTING AND PHASE ONE CONDITIONS DESIGN CONTRIBUTING AREA C2 C10 C100 Tc Tc I2 I10 I100 Q2 Q10 Q100 DESIGN POINT SUB 2,10 100 BASIN(S) ac. min. min iph iph iph cfe cfe cfe rr+♦r+rr♦r+rr♦rrr+♦r+rr++:r++rr+rrrr++rr+rrrr+:r+r+r♦rrrrrr+r+rrrrrrrwrwrrwrrrrwrwrrrrwr+wrr+r:+rrrrrw EXISTING CONDITIONS EXISTING CONDITIONS A Ia 0.34 0.45 0.45 0.56 5.00 5.00 3.29 5.64 9.30 0.50 0.86 1.77 DST POND B Ib & Imwb 0.58 0.65 0.65 0.82 5.00 5.00 3.29 5.64 9.30 1.24 2.13 4.42 STREET C Ic & Irowc 0.26 0.60 0.60 0.75 5.00 5.00 3.29 5.64 9.30 0.51 0.88 1.81 I/P SITE ONLY SITS ONLY B Ib 0.24 0.42 0.42 0.52 5.00 5.00 3.29 5.64 9.30 0.33 0.57 1.16 STREET C Ic 0.13 0.43 0.43 0.54 5.00 5.00 3.29 5.64 9.30 0.18 0.32 0.65 I/P PHASE 1 CONDITIONS PHASE 1 CONDITIONS A Ia 0.34 0.66 0.66 0.83 5.00 S.00 3.29 5.64 9.30 0.74 1.27 2.62 DET POND ABBREVIATIONS NOTE: THERE IS NO CHANGE TO SUBBASINS Ib,Ic,Irowb, AND Irowc DURING PHASE 1 I/P INLET AND PIPE Tc IS NOT A FACTOR IN THE DETERMINATION OF PEAK RUNOFF ONLY THE INCREASE IN IMPERVIOUSNESS AFFECTS THE PEAL( RUNOFF PHASE 1 WILL CONSIST OF GRADING AND PAVING EXISTING PARKING LOT FLOW SUMMARY FOR PI KAPPA ALPHA FRATERNITY EXPANSION ULTIMATE CONDITIONS DESIGN CONTRIBUTING AREA C2 C10 C100 Tc Tc I2 I10 I100 Q2 Q10 Q100 DESIGN POINT SUB 2,10 100 BASIN(S) ac. min. min iph iph iph cfe cfe cfe +r+rr+r+r++rr+rrr+rr++rrrrr++r+r++rrrrrrrrr+r+r+r++r+rr+rrr+rrrr+r+rr+r++r+rr+rr+:rrrrrr++rr+trrrrrwrr ULTIMATE CONDITIONS ULTIMATE CONDITIONS A Ia 0.42 0.77 0.77 0.95 5.00 5.00 3.29 5.64 9.30 1.06 1.82 3.71 DBT POND B Ib & Irowb 0.44 0.68 0.68 0.85 5.00 5.00 3.29 5.64 9.30 0.98 1.69 3.48 STREET C Ic & Irowc 0.32 0.65 0.65 0.81 5.00 5.00 3.29 5.64 9.30 0.68 1.17 2.41 I/P SITE ONLY SITE ONLY B Ib 0.10 0.20 0.20 0.2S 5.00 5.00 3.29 5.64 9.30 0.07 0.11 0.23 STREET C Ic 0.19 0.56 0.56 0.69 5.00 5.00 3.29 5.64 9.30 0.35 0.60 1.22 I/P ABBREVIATIONS NOTE: Tc IS NOT A FACTOR IN THE DETERMINATION OF PEAK RUNOFF I/P = INLET AND PIPE ONLY THE INCREASE IN IMPERVIOUSNESS AFFECTS THE PEAK RUNOFF ULTIMATE CONDITIONS WILL CONSIST OF THE FOLLOWING: 1 REMOVAL OF THE EXISTING BUILDINGS ON THE PROPERTY 2 CONSTRUCTION OF 1 FRATERNITY HOUSE FRONTING ON WEST LAUREL STREET 3 FINAL EXPANSION AND PAVING OF THE PARKING LOT SHEAR ENGINEERING CORPORATION PAGE 1 PROJECT :PI KAPPA ALPHA DATE: 10/02/95 PROJ.NO. :1060-02-95 BY: HBO LOCATION :LAUREL STREET FILE: PKACOEF NOTE: AREAS WITHIN THE LIMITS OF THE ROW WILL NOT BE AFFECTED BY THIS PROJECT EXISTING SITE AND ROW BREAKDOWN SUBBASIN AREA C2,10 C100 ASPHALT GRAVEL CONCRETE LAWN ROOF acres 0.95 0.50 0.95 0.20 0.95 Is 0.34 0.45 0.56 0.16 0.13 0.05 Ib 0.24 0.42 0.52 0.02 0.17 0.05 Ic 0.13 0.43 0.54 0.01 0.09 0.03 SUBTOTAL 0.71 0.00 0.16 0.03 0.39 0.13 Irowb 0.34 0.82 1.00 0.26 0.02 0.06 Irowc 0.13 0.78 0.97 0.08 0.02 0.03 TOTAL 1.18 0.34 0.16 0.07 0.46 0.13 DESIGN BASINS AREA C2,10 C100 POINT B Ib & Irowb 0.58 0.65 0.82 C Ic & Irowc 0.26 0.60 0.75 INTERIM SITE AND ROW BREAKDOWN SUBBASIN AREA C2,10 C100 ASPHALT GRAVEL CONCRETE LAWN ROOF acres 0.95 0.50 0.95 0.20 0.95 Is 0.34 0.66 0.83 0.16 0.13 0.05 Ib 0.24 0.42 0.52 0.02 0.17 0.05 Ic 0.13 0.43 0.54 0.01 0.09 0.03 SUBTOTAL 0.71 0.54 0.67 0.16 0.00 0.03 0.39 0.13 DESIGN BASINS AREA C2,10 C100 POINT B Ib & Irowb 0.58 0.65 0.82 C Ic & Irowc 0.26 0.60 0.75 ULTIMATE SITE BREAKDOWN SUBBASIN AREA C2,10 C100 ASPHALT GRAVEL CONCRETE LAWN ROOF acres 0.95 0.50 0.95 0.20 0.95 Is 0.42 0.77 0.96 0.23 0.01 0.10 0.08 Ib 0.10 0.20 0.25 0.10 Ic 0.19 0.56 0.69 0.01 0.10 0.08 SUBTOTAL 0.71 0.23 0 0.02 0.3 0.16 DESIGN BASINS AREA C2,10 C100 POINT B Ib & Irowb 0.44 0.68 0.85 C Ic & Irowc 0.32 0.65 0.81 SHEAR ENGINEERING CORPORATION EXISTING CONDITIONS SURFACE STREETS ASPHALT CONCRETE GRAVEL G$1.3;K LAWNS SANDY SOIL PLAT < 2% AVERAGE 2 - 7% STEEP > 7% LAWNS HEAVY SOIL COMPOSITE RUNOFF COEFFICIENTS PAGE 2 PROJECT :PI KAPPA ALPHA PROJ.NO. :1060-02-95 DATE: 10/02/95 LOCATION :LAUREL STREET BY: MEO PILE :PKACOEF NOTES :SITE ONLY DOES NOT INCLUDE ROW RUNOFF COEF. (acres) 0.000 0.950 0.000 0.030 0.950 0.029 0.160 0.500 0.080 0.130 0.950 0.124 0.000 0.100 0.000 0.000 0.150 0.000� 0.000 0.200 0.000 PLAT < 2% 0.390 0.200 0.078 AVERAGE 2 - 7% 0.000 0.250 0.000 STEEP > 7% 0.000 0.350 0.000 TOTAL AREA 0.710 0.310 C2 C10 C100 COMPOSITE C VALUE 0.437 0.437 0.546 USE 0.44 0.44 0.56 A SHEAR ENGINEERING CORPORATION PHASE 1 DEVELOPED CONDITIONS COMPOSITE RUNOFF COEFFICIENTS PAGE 3 PROJECT :PI KAPPA ALPHA PROJ.NO. :1060-02-95 DATE: 10/02/95 LOCATION :LAUREL STREET BY: MEO PILE :PKACOEF NOTES :PARKING LOT PAVED ONLY DOES NOT INCLUDE ROW RUNOFF SURFACE CORP. CHARACTERISTICS AREA C C*A (acres) STREETS ASPHALT 0.160 0.950 0.152 CONCRETE 0.030 0.950 0.029 GRAVEL 0.000 0.500 0.000 ROOFS 0.130 0.950 0.124 LAWNS SANDY SOIL PLAT < 2% 0.000 0.100 0.000 AVERAGE 2 - 7% 0.000 0.150 0.000 STEEP > 7% 0.000 0.200 0.000 LAWNS HEAVY SOIL PLAT < 2% 0.390 0.200 0.078 AVERAGE 2 - 7% 0.000 0.250 0.000 STEEP > 7% 0.000 0.350 0.000 TOTAL AREA 0.710 0.382 C2 CIO C100 COMPOSITE C VALUE 0.538 0.538 0.673 USE - 0.54 0.54 O.L7 SHEAR ENGINEERING CORPORATION ULTIMATE CONDITIONS COMPOSITE RUNOFF COEFFICIENTS PAGE 4 PROTECT :PI KAPPA ALPHA PROJ.NO. :1060-02-95 DATE: 10/02/95 LOCATION :LAUREL STREET BY: MEO FILE :PKACOEF NOTES :PARKING LOT PAVED DUPLEX REMOVED & NEW BUILDING = 70*100 DOBS NOT INCLUDE ROW RUNOFF. SURFACE CORP. CHARACTERISTICS AREA C C*A (acree) STREETS ASPHALT 0.230 0.950 0.219 CONCRETE 0.020 0.950 0.019 GRAVEL 0.000 0.500 0.000 ROOFS 0.160 0.950 0.152 LAWNS SANDY SOIL FLAT < 2% 0.000 0.100 0.000 AVERAGE 2 - 7% 0.000 0.150 0.000 STEEP > 7% 0.000 0.200 0.000 LAWNS HEAVY SOIL FLAT < 2% 0.300 0.200 0.060 AVERAGE 2 - 7% 0.000 0.250 0.000 STEEP > 7% 0.000 0.350 0.000 TOTAL AREA 0.710 0.450 C2 C10 C100 COMPOSITE C VALUE 0.633 0.633 0.791 USR 0.63 0.63 0.79 SHEAR ENGINEERING CORPORATION EXISTING CONDITIONS PAGE 5 FLOW TO CONCENTRATION POINT A FROM SUBBASIN Ia PROJECT: PI KAPPA ALPHA FRATERNITY EXPANSION DATE 10/02/95 FILE: PKARUN PROJ. NO.1060-02-95 NOTES: BY HBO AREA (A)- 0.340 ACRES RUNOFF COEF. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.45 0.45 0.56 SEE SPREAD SHEET ATTACHED ON PAGE 4 TIME OF CONCENTRATION (TO - Tc IS ASSUMED BASED ON THE SIZE OF -THE BASINS OVERLAND TRAVEL TIME (Ti) NOT APPLICABLE LENGTH =? FRET SLOPE _? t 2 YEAR 10 YEAR 100 YEAR C =? ? ? Ti (min)= 0.00 0.00 0.00 NOT APPLICABLE TRAVEL TIME (It) =L/(60*V) FLOW TYPE L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 NOTE: ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 0.00 Tc =Ti+TOTAL TRAVEL TIME - ASSUMED BASED ON SIZE OF BASIN 2 YEAR 10 YEAR 100 YEAR Tc (min)= 0.00 0.00 0.00 USE Tc 5 5 5 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 3.29 5.64 9.30 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (cfs) 2 YEAR 10 YEAR 100 YEAR Q = 0.50 0.86 1.77 CONCLUDE:USE 2 YEAR FLOW FOR RELEASE RATE FROM DETENTION POND PAGE 6 PROJECT: PI KAPPA ALPHA PILE: PKARUN NOTES: AREA (A)= 0.580 ACRES SHEAR ENGINEERING CORPORATION EXISTING CONDITIONS PLOW TO CONCENTRATION POINT B FROM SUBBASIN Ib & Irowb DATE 10/02/95 PROD. NO.1060-02-95 BY MEO 1 RUNOFF CORP. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.65 0.65 0.82 SEE SPREAD SHEET ATTACHED ON PAGE 4 TIME OF CONCENTRATION (Tc) - Tc IS ASSUMED BASED ON THE SIZE OF THE BASINS OVERLAND TRAVEL TIME (Ti) NOT APPLICABLE LENGTH =? FEET SLOPE _? 4 2 YEAR 10 YEAR 100 YEAR C =? ? ? Ti (min)= 0.00 0.00 0.00 NOT APPLICABLE TRAVEL TIME (Tt)=L/(60•V) FLOW TYPE L (ft) _? S ($) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (4) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S ($) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (4) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (4) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (4) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (4) _? ? V (fps) _? Tt(min)= 0.00 NOTE: ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 0.00 Tc =Ti+TOTAL TRAVEL TIME - ASSUMED BASED ON SIZE OF BASIN - 2 YEAR 10 YEAR 100 YEAR Tc (min)= 0.00 0.00 0.00 USE Tc = 5 5 5 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 3.29 5.64 9.30 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (Cfs) 2 YEAR 10 YEAR 100 YEAR Q 1.24 2.13 4.42 CONCLUDE:COMPARE WITH ULTIMATE CONDITIONS PAGE 7 PROJECT: PI KAPPA ALPHA PILE: PKARUN NOTES: AREA (A)= 0.260 ACRES SHEAR ENGINRBRING CORPORATION EXISTING CONDITIONS FLOW TO CONCENTRATION POINT C FROM SUBBASIN Ic & Imwc DATE 10/02/95 PROJ. NO.1060-02-95 BY HBO RUNOFF CORP. (C) 2 YEAR 10 YEAR 100 YEAR C 0.60 0.60 0.75 SEE SPREAD SHEET ATTACHED ON PAGE 4 TIME OF CONCENTRATION (Tc) - Tc IS ASSUMED BASED ON THE SIZE OF THE BASINS OVERLAND TRAVEL TIME (Ti) NOT APPLICABLE LENGTH =? FEET SLOPE _? t 2 YEAR 10 YEAR 100 YEAR C =7 ? ? Ti (min)= 0.00 0.00 0.00 NOT APPLICABLE TRAVEL TIME (Tt)=L/(60*V) FLOW TYPE L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (t) _? ? V (fps) _? Tt(min)= 0.00 NOTE: ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 0.00 Tc =Ti+TOTAL TRAVEL TIME - ASSUMED BASED ON SIZE OF BASIN 2 YEAR 10 YEAR 100 YEAR Tc (min)= 0.00 0.00 -0.00 USE Tc = 5 5 5 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 3.29 5.64 9.30 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q- CIA) (cfe) 2 YEAR 10 YEAR 100 YEAR Q = 0.51 0.88 1.81 CONCLUDE:COMPARE WITH ULTIMATE CONDITIONS SHEAR ENGINEERING CORPORATION J ULTIMATE CONDITIONS PAGE 8 FLOW TO CONCENTRATION POINT A FROM SUBBASIN Is PROJECT: PI KAPPA ALPHA FRATERNITY EXPANSION DATE 10/02/95 FILE: PKARUN PROD. NO.1060-02-95 NOTES: BY MHO AREA (A)= 0.420 ACRES RUNOFF COEF. (C) 2 YEAR 10 YEAR 100 YEAR C 0.77 0.77 0.95 SEE SPREAD SHEET ATTACHED ON PAGE 4 TIME OF CONCENTRATION (Tc) - Tc IS ASSUMED BASED ON THE SIZE OF THE BASINS OVERLAND TRAVEL TIME (Ti) NOT APPLICABLE LENGTH =? FEET SLOPS =? t 2 YEAR 10 YEAR 100 YEAR C =? ? ? Ti (min)= 0.00 0.00 0.00 NOT APPLICABLE TRAVEL TIME (Tt) =L/(60*V) FLOW TYPE L (ft) _? S C0 _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (a) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (i) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S M _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (k) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (6) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S ($) _? ? V (fps) _? Tt(min)= 0.00 NOTE: ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 0.00 Tc =Ti+TOTAL TRAVEL TIME - ASSUMED BASED ON SIZE OF BASIN 2 YEAR 10 YEAR 100 YEAR Tc (min)= 0.00 0.00 0.00 USE Tc = 5 5 5 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 3.29 5.64 9.30 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (cfS) 2 YEAR 10 YEAR 100 YEAR Q = 1.06 1.82 3.71 CONCLUDE:RESTRICT FLOWS TO EXISTING 2 YEAR RELEASE RATE PAGE 9 PROJECT: PI KAPPA ALPHA FILE: PKARUN NOTES: AREA (A)- 0.440 ACRES SHEAR ENGINEERING CORPORATION ULTIMATE CONDITIONS FLOW TO CONCENTRATION POINT B FROM SUBBASIN Ib & ITowb DATE 10/02/95 PROJ. NO.1060-02-95 BY MEO RUNOFF CORP. (C) 2 YEAR 10 YEAR 100 YEAR C = 0.68 0.68 0.85 SEE SPREAD SHEET ATTACHED ON PAGE 4 TIME OF CONCENTRATION (Tc) - Tc IS ASSUMED BASED ON THE SIZE OF THE BASINS OVERLAND TRAVEL TIME (Ti) NOT APPLICABLE LENGTH =? FEET SLOPE =7 k 2 YEAR 10 YEAR 100 YEAR C =? 7 ? Ti (min)= 0.00 0.00 0.00 NOT APPLICABLE TRAVEL TIME (Tt)=L/(603V) FLOW TYPE L (ft) _? S (k) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (k) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (k) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (k) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (k) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (k) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (k) _? ? V (fps) _? Tt(min)= 0.00 NOTE: ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 0.00 Tc =Ti+TOTAL TRAVEL TIME - ASSUMED BASED ON SIZE OF BASIN 2 YEAR 10 YEAR 100 YEAR Tc (min)= 0.00 0.00 0.00 USE Tc = 5 5 5 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR I = 3.29 5.64 9.30 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (cfs) 2 YEAR 10 YEAR 100 YEAR Q = 0.98 1:69 3.48 QEXIST = 1.24 2.13 4.42 DELTA ® B -0.26 -0.44 -0.94 CONCLUDE:DEVELOPMENT REDUCES FLOW TO 'B' FROM SITE 9 PAGE 10 PROJECT: PI KAPPA ALPHA FILE: PKARUN NOTES: AREA (A)= 0.320 ACRES SHEAR ENGINEERING CORPORATION ULTIMATE CONDITIONS FLOW TO CONCENTRATION POINT C FROM SUBBASIN Ic & Imwc DATE 10/02/95 PROD. NO.1060-02-95 BY HBO RUNOFF COEF. (C) 2 YEAR 10 YEAR 100 YEAR C 0.65 0.65 0.81 SEE SPREAD SHEET ATTACHED ON PAGE 4 TIME OF CONCENTRATION (TO - Tc IS ASSUMED BASED ON THE SIZE OF THE BASINS OVERLAND TRAVEL TIME (Ti) NOT APPLICABLE LENGTH =7 FEET SLOPE _? It 2 YEAR 10 YEAR 100 YEAR C =? ? ? Ti (min)= 0.00 0.00 0.00 NOT APPLICABLE TRAVEL TIME (Tt)=L/(60*V) FLOW TYPE L (ft) _? S (}) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (&) _? ? V (fps) _? Tt(min)= 0.00 L (£t) _? S (}) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (}) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (}) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (}) _? ? V (fps) _? Tt(min)= 0.00 L (ft) _? S (%) _? ? V (fps) _? Tt(min)= 0.00 NOTE: ALL VELOCITIES TAKEN FROM FIGURE 3-2 TOTAL TRAVEL TIME (min) = 0.00 Tc =Ti+TOTAL TRAVEL TIME - ASSUMED BASED ON SIZE OF BASIN 2 YEAR 10 YEAR 100 YEAR Tc (min)= 0.00 0.00 0.00 USE Tc = 5 5 5 INTENSITY (I) (iph) 2 YEAR 10 YEAR 100 YEAR 1 = 3.29 5.64 9.30 NOTE: INTENSITIES TAKEN FROM FIGURE 3-1 RUNOFF (Q= CIA) (cfs) 2 YEAR 10 YEAR 100 YEAR Q = 0.68 1.17 2.41 0.51 0.88 1.81 DELTA ® C +0.17 +0.29 +0.78 DELTA @ B -0.26 -0.44 -0.94 CONCLUDB:THB REDUCTION IN FLOW TO 'B' OFFSETS THE INCREASE IN FLOW TO C SHEAR BNGINSBRING CORPORATION PAGE X DETENTION VOLUME REQUIRED FOR PHASE 1 DEVELOPED CONDITIONS PROJECT: Pi Kappa Alpha Expansion DATE: 10/03/95 PROJ.NO. 1060-02-95 FILE: PKACUHP BY MEO CUMULATIVE RUNOFF METHOD FOR SIZING DETENTION PONDS DESIGN STORM: 100 YEAR RUNOFF COEFFICIENT 0.67 RELEASE RATE: 0.50 CFS AREA: 0.71 ACRES INITIAL TIME: 5 MINUTES TIME INCREMENT: 5 MINUTES INFLOW INFLOW RELEASE STORAGE STORAGE TIME TIME INTENSITY RATS VOLUME VOLUME VOLUME VOLUME min sec iph cfs cf cf cf ac-ft rxrxxrrxxrxrrxrxxxrrrrxrrr++rxrx++rr+x++r+r+rr+xrx++rxrrxxrxxxxrxrrxxrxr 5 300 9.30 4.42 1327.2 150.0 1177.2 0.03 10 600 7.14 3.40 2037.9 300.0 1737.9 0.04 15 900 6.06 2.88 2594.5 450.0 2144.5 0.05 20 1200 5.21 2.48 2974.1 600.0 2374.1 0.05 25 1500 4.63 2.20 3303.7 750.0 2553.7 0.06 30 1800 4.20 2.00 3596.3 900.0 2696.3 0.06 35 2100 3.81 1.81 3806.1 1050.0 2756.1 0.06 40 2400 3.02 1.44 3447.9 1200.0 2247.9 0.05 45 2700 2.80 1.33 3596.3 1350.0 2246.3 0.05 50 3000 2.60 1.24 3710.5 I500.0 2210.5 0.05 55 3300 2.43 1.16 3814.6 1650.0 2164.6 0.05 60 3600 2.30 1.09 3938.8 1800.0 2138.8 0.05 65 3900 2.17 1.03 4025.8 1950.0 2075.8 0.05 rxr+xrr+x+rxrrrxxxrrrrrrrrrrrrrrr+rrrrrrrrrrrrrrrrrr+xr+r++rx+x+xtxrxrxr DETENTION VOLUME REQUIRED = 2756.08 CF NOTES: 1 RELEASE RATE BASED ON HISTORIC Q2 (0.50 CFS) FROM SUBBASIN Is SHEAR ENGINEERING CORPORATION PAGE DETENTION VOLUME REQUIRED FOR ULTIMATE CONDITIONS PROJECT: Pi Kappa Alpha Expansion DATE: 10/03/95 PROJ.NO. 1060-02-95 PILE: PKACUHP BY MHO CUMULATIVE RUNOFF METHOD FOR SIZING DETENTION PONDS DESIGN STORM: 100 YEAR RUNOFF COEFFICIENT 0.79 RELEASE RATE: 0.50 CPS AREA: 0.71 ACRES INITIAL TIME: 5 MINUTES TIME INCREMENT: 5 MINUTES INFLOW INFLOW RELEASE STORAGE STORAGE TIME TIME INTENSITY RATE VOLUME VOLUME VOLUME VOLUME min sec iph cfs cf cf cf ac-ft •rrrrrrrrrr:rrrrrrxxxrrrrrrrrrrerrrrrrrrrrr:rrr+rxrrrrrrrrrrrrrr:rrrrrrr 5 300 9.30 5.22 1564.9 150.0 1414.9 0.03 10 600 7.14 4.00 2402.9 300.0 2102.9 0.05 15 900 6.06 3.40 3059.1 450.0 2609.1 0.06 20 1200 5.21 2.92 3506.7 600.0 2906.7 0.07 25 1500 4.63 2.60 3895.5 750.0 3145.5 0.07 30 1800 4.20 2.36 4240.4 900.0 3340.4 0.08 35 2100 3.81 2.14 4487.8 1050.0 3437.8 0.08 40 2400 3.60 2.02 4846.2 1200.0 3646.2 0.08 45 2700 3.28 1.84 4967.3 1350.0 3617.3 0.08 50 3000 3.02 1.69 5081.8 1500.0 3581.8 0.08 55 3300 2.80 1.57 5182.7 1650.0 3532.7 0.08 60 3600 2.60 1.46 5250.0 1800.0 3450.0 0.08 65 3900 2.43 1.36 5315.6 1950.0 3365.6 0.08 rrrrrrrrrrrrrrrxrrrrrrrrrrrrrrrrrrrr+rrr+r+r+r+r+rrrrrrrr♦rrrrrr++++++r+ DETENTION VOLUME REQUIRED = 3646.18 CP NOTES: 1 RELEASE RATE BASED ON HISTORIC Q2 (0.50 CPS) FROM SUBBASIN Ia SHEAR ENGINEERING CORPORATION AVERAGE END AREA METHOD FOR DETENTION BASIN VOLUMES PHASE 1 POND PAGE 13 PROJECT :PI KAPPA ALPHA DATE: 10/02/95 PROJ. NO:1060-02-95 LOCATION:LAURBL AND MBLDRUM BY MEO PORT COLLINS PILE: PKAAVG CONSTANT: 65 = 1 SQ IN. FIRST EVEN CONTOUR 5000.8 PERT INVERT 5000.6 PERT TOP BLEV 5001.6 PERT INCREMENT 0.2 FOOT SCALE: 1. = 20 FEET rrrrrrrr rrrr:rr: rrrrrrrr rrrrrrrr rrrrrrrr xxxrrxrx rxxrxxxx rx xrrrxr BLEV PLANI- AREA AREA VOLUME CUM. CUM. CUM. METER (Al) (A2) (V1) VOLUME VOLUME VOLUME ft READING sq in aq ft cf cf cy ac-ft xrrrxrrr xrxrrxrr rrrrrrrr rrrrrrrr rrrrrrrr rxrx rrrr xrxrrrrx rrrrrrrr 5000.6 0 0.00 0 0 0 0 0.00 5000.8 69 1.06 425 42 42 2 0.00 5001 287 4.42 1766 219 262 10 0.01 5001.2 641.5 9.87 3948 571 833 31 0.02 5001.4 908 13.97 5588 954 1786 66 0.04 5001.6 1051 16.17 6468 1206 2992 111 0.07 PORMULAE:A1= (PLANIMETER READING)/CONSTANT A2= (A1)*SCALE SQUARED REQUIRED VOLUME = 2756 CUBIC PBET REFER TO PAGE 11 ESTIMATED 100 YEAR W.S. BLBV. = 5001.404 FEET SHEAR ENGINBBRING CORPORATION AVERAGE END AREA METHOD FOR DETENTION BASIN VOLUMES ULTIMATE CONDITIONS PAGE 14 PROJECT :PI KAPPA ALPHA DATE: 10/02/95 PROD. NO:1060-02-95 LOCATION:LAUREL AND MELDRUM BY MEO PORT COLLINS FILE: PKAAVG CONSTANT: 65 = 1 SQ IN. FIRST EVEN CONTOUR 5000.8 FEET INVERT 5000.6 FEET TOP ELEV 5001.6 PERT INCREMENT 0.2 FOOT SCALE: 1" 20 FEET t rrrrrrr rrrrrrrr +r+rxrrx rrrrr+rt rtr+rrrr r+rxrrrr rrrrrrrr rrrrrrrr BLEV PLANI- AREA AREA VOLUME CUM. CUM. CUM. METER (Al) (A2) (V1) VOLUME VOLUME VOLUME ft READING eq in eq ft cf cf cY ac-ft r rrrrrrx •rrrrrrr xrrrrr++ rrxrxrrr r+rrtrtr rr++rrrx xrrrrrxx rrrrrr+r 5000.6 0 0.00 0 0 0 0 0.00 5000.8 69 1.06 425 42 42 2 0.00 5001.0 287 4.42 1766 219 262 10 0.01 5001.2 690 10.62 4246 601 863 32 0.02 5001.4 1361 20.94 8375 1262 2125 79 0.05 5001.6 1661.5 25.56 10225 1860 3985 148 0.09 FORMULAE:A1= (PLANIMETER READING)/CONSTANT. A2= (A1)rSCALE SQUARED REQUIRED VOLUME = 3646.18 CUBIC FRET REFER TO PAGE 11 ESTIMATED 100-YEAR W.S.ELBV. = 5001.417 FEET SHEAR ENGINEERING CORPORATION PAGE 15 PROJECT: PI KAPPA ALPHA DATE: 10/04/95 PROJECT NO 1060-02-95 BY MBO PROJECT LOCATION :LAUREL STREET NOTES: TO BE FILLED IN PILE NAME: PKAOUT INPUT FOR OUTLET STRUCTURE STRUCTURE TYPE: SINGLE ORIFICE WEIR TYPE NA LOWER ORIFICE DIAM. (ft) - 0.33 WEIR LENGTH (ft) = 4.00 LOWER ORIFICE INV. (ft) = 5000.60 WEIR INVERT (ft) = 5001.42 LOWER ORIFICE CORP. (Cl) = 0.65 WEIR CORP. (Cw) = 2.60 UPPER ORIFICE DIAM.(ft) - NA TOP OF BERM (£t) = 5001.60 UPPER ORIFICE INV. (ft) = NA INIT. DELTA (ft) = 0.10 UPPER ORIFICE CORP. (Cu) = NA DELTA HEAD (ft) = 0.20 2 YR. RELEASE RATE (cfe) = HA PHASE 1 W.S.EL RBQ'D(ft) = 5001.40 10 YR RELEASE RATE (cfe) = NA ULTIMATE WSEL RRQ'D (ft) - 5001.42 100 YR RELEASE RATE (cfs)= 0.36 OVER FLOW YES OUTLET PIPE DIAM. (ft) 0.50 WEIR TYPE BROADCRHSTED PIPE SLOPE M 0.40 WEIR LENGTH (ft) = 24.00 MANNINGS n = 0.012 WEIR INVERT (ft) = 5001.60 WEIR COEF. (Cwo) = 2.60 rrtrtr*r*: r*x*x*** ***x**** *OUTPUT* rt*rrr**r *****r*♦ ***r*r** *****♦** PIPE AREA (SF) = 0.20 WETTED PERIMETER = 1.57 FEET HYD. RAD (FT) _ .0 125 FEET. RA2/3 = 0.2498 ' OUTLET PIPE CAPACITY = 0.38 CPS LOWER ORIFICE AREA (A) = 0.0855 SQUARE FEET UPPER ORIFICE AREA (A) = 0.0000 SQUARE FEET ******* *+rrrrr rrr*rrr *OUTPUT+ ******r ******r ++*rtrr* rrrrr*+ HEAD HEAD HEAD SUB RLEV. OVER LOWER OVER UPPER OVER WEIR TOTAL LOWER ORIFICE UPPER ORIFICE WHIR FLOW FLOW ORIFICE FLOW ORIFICE FLOW ft ft cfe ft cfs ft cfe cfe 5000.60 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5000.70 0.10 0.14 0.00 0.00 0.00 0.00 0.14 5000.90 0.30 0.24 0.00 0.00 0.00 0.00 0.24 5001.10 0.50 0.32 0.00 0.00 0.00 0.00 0.32 5001.30 0.70 0.37 0.00 0.00 0.00 0.00 0.37 5001.50 0.90 0.42 0.00 0.00 0.08 0.24 0.66 5001.60 1.00 0.45 0.00 0.00 0.18 0.79 1.24 5001.47 0.87 0.42 0.00 0.00 0.05 0.12 0.53 5001.42 0.82 0.40 0.00 0.00 0.00 0.00 0.40 rtrt*rrr+x +rtrtrrx++ +xtxrt+++ ++rrr+++ +rrtxrtrtrtr rtrtrtrtrtrtrtrt +rtrrrrtrtrt +rrrrr*+ ORIFICE EQUATION: CA(2gH)^1/2 WEIR FLOW EQTN. : CwLH^3/2 t • ins' r »Yy j S � / t = «7 .•I1 •. J • 1J• WO -Pa IWJP IS • A •• •• . •FYI. ' W.1♦•( q.•N• � ♦'fit+ \�• _ .._ �_.. G a /r Q * w 1' •i : .•unr 4 OL _ tL• J �' (J t ji is r fall _ 1• V ...IINw - J j • is is I tI: r •, V O / � w • ( irI ( ` 1 • I ' n s , 1 6 a• a ... ..It. rl.w W . •1 I ' . • _I 1 1 r •► J i C T •�. • is I»r '.M • • • 1] ✓Y . is �•✓•• -pp.& t, . ••i1 Inn.7 11.04 72 q.» t{tt� L•-r•• + RAINFALL PERFORMANCE STANDARD EVALUATION PROJECT: ?N Vr)P?'a WOPV+A 0,11.E STANDARD FORM A COMPLETED BY: pr -y DATE: 14I 5s DEVELOPED ERODIBILITY Asb Lsb Ssb Lb Sb PS SUBBA$IN ZONE (ac) (ft) M (feet) M M RAT�ZU <1'Jr 1Ob 7b, \-1-0 X :_ 2W �, Fro") � R MARCH 1991 8-14 DESIGN CRITERIA EFFECTIVENESS CALCULATIONS PROJECT: p V-t?YFP STANDARD FORM B COMPLETED BY: DATE: I04 5S Erosion Control C-Factor P-Factor Method Value Value Comment O,o\ 1,0 Q.US.r.,G. MAJOR PS SUB AREA BASIN BASIN (Ac) CALCULATIONS J O,o�ou X C�Ux,z�I` O , Ze, Cxos�u�J c \s MARCH 1991 B-15 DESIGN CRITERIA y October 24, 1995 Project No. 1060-02-95 Basil Hamdan City of Fort Collins Storm Water Utility P.O. Box 580 Ft. Collins, Colorado 80522 Re: Phase 1: Pi Kappa Alpha Fraternity Expansion; Fort Collins, Colorado Dear Basil, Attached is the erosion control security deposit estimate for Phase 1 of the Pi Kappa Alpha Fraternity Expansion project. Phase 1 only consists of the paving of the existing parking area. ESTIMATE 1: 1 - Hay bale barrier at area inlet ® 75.00 each 1 - Gravel Inlet Filter ® 75.00 each TOTAL ESTIMATED COST: ESTIMATE 2: re -vegetate the disturbed area of 0.20 acres at $1,300.00 per acre TOTAL ESTIMATED COST: $ 75.00 $ 75.00 $ 150.00 x 1.50 $ 225.00 260.00 $ 260.00 x 1.50 S 390.00 In no instance shall the amount of the security be less than $1000.00. Therefore, the total required erosion control security deposit for Phase 1 of the Pi Kappa Alpha expansion will be $1,000.00. If you have any questions, please call, at Sincerely,Z119 .20262 'Sae= *cVM Brian W. Shear, P.E.��,(� Shear Engineering Corp oration BWS / mb ''`ytii;. ; auumnu cc: Amshel Corporation Dave Stringer, City of Fort Collins 4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282-0311 APPENDIX H Charts & Figures No Text APPENDIX III Stuffer Envelope Drainage and Erosion Control Plan (Ultimate Conditions) Phase 1 Grading Plan Ultimate Conditions Grading plan Erosion Control Security Deposit Document October 24, 1995 Project No. 1060-02-95 Re: EROSION CONTROL., SECURITY DEPOSIT REQUIREMENTS: Phase 1: Pi Kappa Alpha Fraternity Expansion; Fort Collins, Colorado A. An erosion control security deposit is 'required in accordance with City of Fort Collins policy (Chapter 7, Section C : SECURITY; page 7.23 of the City of Fort Collins Development Manual). In no instance shall the amount of the security be less than $1000.00. 1. According to current City of Fort Collins policy, the erosion control security deposit is figured based on the larger amount of 1.5 times the estimated cost of installing the approved erosion control measures or 1.5 times the cost to re -vegetate the anticipated area to be disturbed by construction activity. i The cost to install the proposed erosion control measures is approximately $150.00. Refer to the cost estimate attached in Appendix I. 1.5 times the cost to install the erosion control measures is $ 225.00. ii. Based on current data provided by the City of Fort Collins Stormwater Utility, and based on an actual anticipated net affected area which will be disturbed by construction activity (approximately 0.20 acres), we,estimate that the cost to re - vegetate the disturbed area will be $260.00 ($1,300.00 per acre x 0.20 acres). 1.5 times the cost to re -vegetate the disturbed area is $390.00. The $1,300.00 per acre for re -seeding sites of less than 1 acre was quoted to us by the City of Fort Collins Stonnwater Utility staff. CONCLUSION: The erosion control security deposit amount required for Phase 1 of the Pi Kappa Alpha Fraternity Expansion will be S 1,000.00. 4836 S. College, Suite 12 Ft. Collins, CO 80525 (970) 226-5334 FAX (970) 282.0311 lel llEr . con. wlulnnns I'.I GW. ARAGE AN. &�Awpimo Ralw rxna.z' rl L - - -- W. DChrMtl — _ n aao a% 5W w15 5nm5n AREA IL7 INLET ! L $ n �pSGIE: �I'=RIY I GRAVELNg�1L1E QM, \iLLRiEN USING NALI !0 n Un A LATISM 50 AMOUNT IWALNAGLMALNI'ENANCE NOTE l e IN J a al RL P aRRRNNrh ' maRuP . Fm rc p, ALI 1 and a M1u M1v Le PLAN, N, IM mua Wirvtl RNW4'ir IkLNAu, _..- rtr�rohfmr.Ir. vlen N.urvnurc uai ruhr4vrwlwr. raLW Da EXIST. GARAGE I I II SgaOi1�7 _ F I 1. F_G I_\ D PROPOSED STORM SEWER II 1 r 11 A 1 U 4. UnRI Ia SUTASM RESIGNATION O CONCE"nnn°N FDENT �— FLOW ome N EROSION CONTROL LEGEND cuvEL MverFLLlu AEEw Mlcr vLLn�e fLLt YEYCE 1.1O1e. EXISTING HOUSE 2 Ib 0.24Ac. �ANANN 9113Ae. Imo. —J L� 50n5 I uwc 0.1701D. WEST LAUR G9lNtlG .Rn u'E GHY9,L IpTCY AaL�maYwY We_ei. pryd m uyuw[ L IA�r..N n.rr amm amf rarye.am _.4 A� S� b a .11e+l �I1Ja Cab INN4I. .I WI.1 x �,��OY�Y,i7 yYyyyx wWm d Y "� W b \inxu"JUL FINAL I DAMN, ANN AN,A, ANNA"..Is AR AN Pr ae°uWL1 FOR r. IIN\\ .'nweuieu L\.Yen/y.rlµn.yl4n J•5-W iw,i Via'_....._ .Ran"'""rr t .7aawUi..._r.� PP ....,-"M kI.,„", a LA... o-n, rr oW .m W u„e 4w�b'Ywm xr.. pW.NnP. Ru n it r r n. , •1 1. • .. 4 n.lu fW.b �'U"sWx•yRe .r.wnR ... ONuel°Omr.Jy WIxTRRaIf O_p� ok. `aruwNNNR `°'PAAVIpIuRVRRew PI .e S d�YY�w Wk4W�lI.IW9Y�`y ���1,11,51w✓ •• =R14 .b.�fYy�y�� .1...a DI ... .. "WAR ANSI SY .. IL w ��SNs s W tL r ems. CWi or bmmiray Ry{BAN•�SY In ISkNA SIR 41AWA,I.i mW Y `, Y��MJNA m i•n,. ran, ,uu.,..mn OwNLe w W M1 N-s Rry^�NNIW. INWM.iS � w✓ M tin I&N, "W .Le Sw IiT-1 rNs Ike J J ..,4 rTJrI9 on 11 Fund Summary -PLaxcl Id.....,.r v M ei :N..Y.P, ..r mrrr. F,.„b. ek.. Sall A -0 07 W it . . .,. w,) K WgamO .. n 6,SNn Sk NdI s. Ek.. 5ml..nbr bat oainhl-03ARN, -071"Na dl Iwbk .awv.-05o.'G b5W _------------- PROJECT BENCHMARK Fire Hydrant at NE comer of intersection of Meldmm and Laurel Norfiremn bmulet bolt Ele,arion - 5002.54 Ref : City of For[ Collins Black Holt Survey --------------------------- ----------------� I I I I I I — — — — — — — — — — — — — — — — — — — — — — — — MNmxn UTILITY PLAN APPROVAL o 9 tt' ..rc. s....q ,..,r. .,. MCI„m RR 9EvmDNs oa. -..._ N°["— ku,- __._. -_ k— rcmNe� _ _ AIR—_ ey_-- w.mryee 9nk EPTENBER, 1995 NTSP CAONNe/[R um AMSHEL CORPORATION P.O. BOX I IN)Ri LLBi3, COIOIG00 80522 CO SHEAR ENGINEERING CORPORATION A 11 W. COLLEGE AVE. SUITE 12, FORT COUL NS. COLORADO ew25 PHONE: (970) 226-533A (970) 226-AA51 FAX: (970) 282-0311 n'H PHASE I GRADING, DRAINAGE AND EROSION CONTROL PLAN PI KAPPA ALPHA FRATERNITY FORT COLLINS. COLORADO Pnmm, "°. ]080-02-RS SNLR "°' Read Book I Scue clreckel B.W.S./NEo 1 2 = 20' MPaWn B.W.S. rrADEr�em�aAIDACE wnEBALrwn v�w aw,. wo w.r wm YrdJYP uEat III•.0 "Ir YqM aNO pNO am •.•v va dIII �N-1 I ay+is lrtilW •amru w,�.+ WALL I'll cr• • GoGor.0 OWN spank II ppapar AGE IN L J II n.rr ewr5rr n�nuxna+FE I.I r wv - I CORNING" W.It �w•�..�.•: au �rwr. a.• .1.,..n N,111 .. 1. RANGING, WAY 11 .. uw. w,a.,n rt.w,w SGO °OSHEx«ooO STREET I I di. E.wam nrmEORIENNE I - r a �! uw 'w` III Nr. B-9mm • - - - 9 ...I . a,.,emm w.. _, „e ,. . „ ,,. o.. w a,• all, w. _ mmr su o x - ' lu r�r n '°, - 1-I Bao d R 7 a 04 _ x. o'"°+ 1= � . ALLEY _ -- ool s9 � �� lit • -- ,wl.a -.: ,GANG , ., .., •• ..• , ... ANSI .. I "WORNW1 _ '«vo1—zo s sale A SON, u — � W _ 1 1 == AD.Maxkx Wamp IN� TwSw.. w.WWI d AREA RLEr FILTER/1 •n.' 1 a.B w SIGN STRAW BALES Ir sd4a I'_d 1 1 , d ^ vv nw. w nn ww ,w ,uw. nVnrarAa�w. •wA+. a.. Sex '��I1.•eo 1500 f. bar r N + RAN µ* •,r w w,wuie uvAr a ,a wo vA AN -JID% 1 V I sYYJ Y r1� rvw. m .m yr 1 Lxabd. MydB�4li W. Nun rtw r w �YHWWHI pas NGANRF, r Rat NOW, Iy awu n . ,�o.r w mx'n,ciWR or vm.,ry m. EiISTHG ASRYLT IOr.E.x»EL.SOn .B � rowb I , P PARKING LE - t '�. i1 I sruc raw mU - IS wnl + -- - I ,I.n, BomdlW.lrvaFn .BRuxN 9 IB:BmSxYi oxFCE• I _ 91 Tgd4 dn.0-amsxG, IRAINAGE31ALNTENANCE NO I L ,•. 0.C2Ac. I g0119 I -" �II�Fv,.,.mlWn...srol.e-MIA"(ms.cb. Tm) S .�1RIpIX I agrci r�ET 1 �•^ o.m.r RANI emrA0444 •frt L 1 la m L _ _ IW IOW Eb. - SAN AR/m "N LInw,.s Hw RVNia, -NU., 6 EGGS I J v.Jamws eh.n Js mwdrt mfwh.luwl..u. .�. I /y Iran TmlfmnWurM '� I•Y luy aRAW 6W Lnt, 'll 10 Tim Pv.liu. USAGE whk OppapImnamlonmm 0500. ff - t I i II I � II Ib Ta. E e� — — I �2B !! Q rl'°°°ar, J---------- 1 I EXISTING I, OUTLET STRUCTURE SORORITY HOUSE I IC 0.1DADM135 1 1 * ".., �., U 1 I pia ". -------- �,, — — — lr--=---------- ---------- — �� E4.B cCaOGppNaEpGpGaI it AmmUm MEW NEW BORROW LEGEND — --- — — --- rowc.5 =u.,aR,» 1 >a..... - - - - - MOROSED STORY SEWER ��' — _ _ ❑ _ _ _ _ _ AREA INLET FILTER�CORII ImLFi I-i se BASDIEdIMDARY—R�-0.TTAC. Dom•, \ IAeWi�s�a�r BILT FEXCE _GROWLINGLY.., kEL5 I \L\l/ _ STRAW �LEs _ O SASUDESIGNATION wY-lRE"' \ I "rtnu tl ScaoR,tO AWWWWWWAGI ,h [L .� W. Gr. VTR FORT I sumA BOUNDARY (a eL NE. FILTER — ^� —' �:—� u_ DOE suBAsw DrsmxSnoN —wz — — CONCINTRAnDNFOBPr SEzs— FLowDIRECnON EROSION CONTROL LEGEND WI'.,Srr LAUREL STREET A construction sequence schedule is IT br snlnldued to the tilonnw ate, Utility in conjunction with the submitlal of the dWWI GRAY INIJIFmT6R building permit application for the Bous(ructiou of the neo AxYA INLET FD.TER building LET BE FEE w.uxs woNno SULTFENCE UTILITY PLAN APPROVAL ------------------------------------------------------- - `� at EECImn PROIECTRENC$DdA$$ Have m or RYdexnlaLNE amurof imersenian o(MelNum and lauM .—arum .,,. Narthua - 5002 bolt Eefem n - 5002.3<IN al® er Re(genm: esly of Fort CallirvN BluE Boh Survey .ww min, AMSHEL CORPORATION SHEAR ENGINEERING CORPORATION FINAL GRADING, DRAINAGE AND EROSION CONTROL PLAN SHEET NO. ALYI610x5 ONe IISE lSSS Ommn CA01rax uDrt TITLE +OF °j ortmrow Fab BSE_ ISRJFB B.W.S. P.O. BOX 1978 y36 SO. COLLEGE "I SUITE 12, FORT COLLINS, COLORADO eoszs PI KAPPA ALPHA FRATERNITY HOUSE Ef 2 1060-02-95 L __ B, . Im"GA ._.-_ Octa l a 20 AwmM B.W.S. FORT COLLINS. CO]ARADO 80522 PHONE: f970) 226-533A (9T0) 226-aa551 FAE: (9T0) 262-0311 FORT COLLINS. COLORADO