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Design & Development Consulting Group, p.s.c.

HYDROLOGIC-HYDRAULIC STUDY FOR STORMWATER MITIGATION AT MERCADO CENTRAL, AT BECHARA SECTOR Hato Rey Ward San Juan, P.R. Submitted to: INCATEMA CONSULTING

(July 19,2012)

APARTADO 19027 • SAN JUAN • PUERTO RICO • 00910-1027 TELEFONO: 787-282-8288 • FAX: 787-282-8269


TABLE OF CONTENTS INTRODUCTION ................................................................................................................................ 1 PROJECT DESCRIPTION .................................................................................................................... 2 HYDROLOGIC ANALYSIS ................................................................................................................... 3 ANALYSIS ............................................................................................................................. 3 WATERSHED DESCRIPTION ................................................................................................. 3 SOIL CLASSIFICATIONS ........................................................................................................ 4 TIME OF CONCENTRATION ................................................................................................. 5 STORM EVENTS ................................................................................................................... 9 HYDROLOGIC MODEL........................................................................................................ 10 STORMWATER MITIGATION .......................................................................................................... 11 CONCLUSIONS AND RECOMMENDATIONS.................................................................................... 13 REFERENCES ................................................................................................................................... 14 FIGURES AND TABLES APPENDIXES

Hydrologic-Hydraulic Study for Stormwater Mitigation at “Mercado Central”, Bechara Sector, San Juan PR

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INTRODUCTION The Municipality of San Juan proposes the development of a group of land parcels located on State Road PR-2 (John F. Kennedy Avenue), Hato Rey Ward. The land parcels will be developed into a “Mercado Central� or Central Market; a series of warehouse facilities for the storage and distribution of wholesale food and groceries. Currently the land parcels are undeveloped, and due to the proposed development it is necessary to provide stormwater mitigation. The stormwater mitigation plan shall be designed to reduce projected runoff for a project through incorporation of design elements or principles that address the following goals in connection with both construction and long-term operation of the site: 1. Maximize, to the maximum extent practicable, the percentage of permeable surfaces to allow more percolation of stormwater into the ground. 2. Minimize, to the maximum extent practicable, the amount of stormwater directed to impermeable areas. 3. Minimize, to the maximum extent practicable, parking lot pollution through the use of appropriate BMPs such as retention, infiltration and good housekeeping. 4. Provide for appropriate permanent controls to reduce stormwater pollutant load produced by the development site to the maximum extent practicable. These increased runoff rates produced by the urbanization of a watershed may overtax succeeding portions of the larger drainage network causing flooding problems downstream. To circumvent this difficulty, storage facilities are provided to receive the runoff from the developed watershed while releasing water to the larger drainage network at a reduced rate. This reduced rate is determined by using parameters fixed by Puerto Rico regulations. The determination of runoff as part of the hydrologic cycle is intended here. Hydrologic analysis will provide design discharges for different storm events as required for the existing and the proposed conditions. After obtaining the desired runoff increment, a hydraulic analysis of the stormwater mitigation facilities will follow. Once the existing conditions critical points are identified and solutions are provided to them, a hydraulic analysis of the proposed conditions will be made. The proposed stormwater mitigation alternative will be selected based on the most economical and environmental efficient solution that will also comply with all government agencies regulations and standards. This report presents the calculations made to obtain several parameters used in the analysis as well as representative graphics of the existing and proposed conditions. Also, this report presents the results obtained using different computer models, and the conclusions and recommendations based on those results.


PROJECT DESCRIPTION The existing parcels to be impacted are located on State Road PR-2, Hato Rey Ward. The parcels are bounded on the North by State Road PR-2 (John F. Kennedy Avenue), and commercial properties; on the South by a vacant parcel; on the East by the Puerto Nuevo Regional Wastewater Treatment Plant and the Municipal Landfill; and on the West by a commercial property, a vacant parcel and the Bechara Channel. The total parcel area to be developed is of approximately 286,071.49 square meters, 70.69 acres, or 0.110 sq. mi. The site location on the topographic quadrangle is shown on Figure 1, and an aerial photograph of the parcels is shown on Figure 2. EXISTING CONDITION The parcels are undeveloped and covered with vegetation (grass and bushes) on lowlands except a small portion that is used as and access dirt road for a garage shop (auto body parts) located on the Southwest portion of the premises. The existing access dirt road runs thru a length of approximately 500 meters with a width of 6.0 meters. PROPOSED CONDITION The proposed development will be a “Mercado Central” or Central Market and will be composed of a series of buildings and supporting facilities. It will include, an access control station, commercial areas, administration & business center, maintenance building, gas station and food products storage warehouses. There will be an approximate area of 1,055,955 sq. ft. (98,11.44 sq. mts.) of building footprint. In addition there will be parking spaces for vehicles and commercial trucks. A Figure depicting the proposed site plan is shown on Figure 4

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HYDROLOGIC ANALYSIS ANALYSIS The determination of runoff as part of the hydrologic cycle is intended here, specifically, the determination of storm runoff as a portion of the total runoff that reaches specific points of interest by observation or measurements within a relatively short period of time following storm precipitation. In stormwater mitigation studies, determination of the peak rates of runoff for storms of various frequencies of occurrences is of main interest. Knowledge of the magnitude and frequency of floods is essential for the effective design of projects. The Soil Conservation Service Method was used to develop the analysis. The HydroCAD computer model developed by HydroCAD Software uses the SCS Method to obtain the total runoff that reaches the point of interest. The HydroCAD computer model computes the runoff produced during a natural or synthetic storm event. To compute this runoff it is necessary to define some parameters of each hydrographic watershed. Those parameters, applied on mathematical equations already defined, are used in the process of modeling the watershed, resulting in the calculation of hydrographs of flow at the point of interest.

WATERSHED DESCRIPTION AND LAND USE Two watersheds limits were defined using the U.S. Geological Survey Quadrangle of San Juan (Figure 1). Watershed “A” is located on the Northern portion of the parcel and has an approximate area of 112,824.66 square meters equal to 27.88 acres, or 0.043 sq. mi. Watershed “B” is located on the Southern portion of the parcel and has an approximate area of 173,246.83 square meters equal to 42.81 acres, or 0.067 sq. mi.

Existing Conditions: The topography of the site is relatively flat with very mild slopes. The elevations vary from -0.5 to 5.25 meters (Mean Sea Level). There are low areas or depressions where runoff water is ponded and routed to 36” pipes on its North boundary towards Kennedy Avenue. There are also other low laying portions with elevations below Mean Sea Level on the Southern portion towards the Bechara Channel and the Puerto Nuevo River. The existing topography and watersheds is shown on Figure 3. Most of the parcel is covered with bushes, weeds, grasses, and small tress, other portions are covered with mangroves and wetlands and a small portion is bare soil. This land covers were obtained through filed visits and aerial photographs.

Proposed Conditions: The site will be developed by the construction of buildings, facilities and parking areas with impermeable surfaces, such as concrete and asphalt. Due to the fact that the site is located on a flood zone area, a fill of approximately 3 to 4 meters high will be deposited. The proposed facilities will be graded with mild slopes towards the North and Southwest boundaries.

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SOIL CLASSIFICATION Inside a watershed we can find a great variety of soils that differ in surface texture, slope, erosion, humidity and other characteristics that affect the runoff potential. The different types of soils in the watersheds are shown in Figure 5. The only type of soil encountered on the parcel is “Hydraquents, Saline”, with an hydrologic group type “D”. This information was obtained from the “Soil Survey of San Juan Area of Puerto Rico”, published by the U.S. Soil Conservation Service.

C U R VE N U M B ER After obtaining the different soil types and land uses, for both existing and proposed conditions, Curve Numbesr (CN), which represents both soil characteristics as previously described, were computed. AREA "A" EXISTING CONDITION SOIL NAME AND HYDROLOGIC GROUP Hy Hydraquents, Saline (D) Hy Hydraquents, Saline (D)

COVER DESCRIPTION ( COVER TYPE, TREATMENT, AND HIDROLOGIC CONDITION) Herbaceous-grass, weeds, brushes (fair condition) Herbaceous-grass, weeds, brushes (poor condition)

CN T A B L E 89

AREA

AREA

(sq. mt)

(acres)

PRODUCT OF CN x AREA

106,258.22

26.26

2,336.86

93

6,566.44

1.62

150.90

TOTAL =

112,824.66

27.88

2,487.76

WEIGHTED CN =

89

AREA "B" EXISTING CONDITION SOIL NAME AND HYDROLOGIC GROUP Hy Hydraquents, Saline (D) Hy Hydraquents, Saline (D)

COVER DESCRIPTION ( COVER TYPE, TREATMENT, AND HIDROLOGIC CONDITION) Herbaceous-grass, weeds, brushes (fair condition) Herbaceous-grass, weeds, brushes (poor condition)

CN T A B L E 89

AREA

AREA

(sq. mt)

(acres)

PRODUCT OF CN x AREA

168,583.98

41.66

3,707.55

93

4,662.85

1.15

107.16

TOTAL =

173,246.83

42.81

3,814.70

WEIGHTED CN =

Hydrologic-Hydraulic Study for Stormwater Mitigation at “Mercado Central”, Bechara Sector, San Juan PR

89

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AREA "A" PROPOSED CONDITION SOIL NAME AND HYDROLOGIC GROUP Hy Hydraquents, Saline (D) Hy Hydraquents, Saline (D)

COVER DESCRIPTION ( COVER TYPE, TREATMENT, AND HIDROLOGIC CONDITION) Herbaceous-grass, weeds, brushes (good condition) Paved parking lots, roofs, driveways

CN T A B L E 85

AREA

AREA

(sq. mt)

(acres)

PRODUCT OF CN x AREA

24,249.58

5.99

509.34

98

92,490.54

22.85

2,239.77

TOTAL =

116,740.12

28.85

2,749.11

WEIGHTED CN =

95

AREA "B" PROPOSED CONDITION SOIL NAME AND HYDROLOGIC GROUP Hy Hydraquents, Saline (D) Hy Hydraquents, Saline (D)

COVER DESCRIPTION ( COVER TYPE, TREATMENT, AND HIDROLOGIC CONDITION) Herbaceous-grass, weeds, brushes (good condition) Paved parking lots, roofs, driveways

CN T A B L E 85

AREA

AREA

(sq. mt)

(acres)

PRODUCT OF CN x AREA

28,346.29

7.00

595.38

98

144,900.54

35.81

3,508.94

TOTAL =

173,246.83

42.81

4,104.33

WEIGHTED CN =

96

TIME OF CONCENTRATION The time of concentration is the sum of different flow travel times of the runoff, from the most distant point in the drainage area to the point of interest. The travel time was determined for the watersheds using the methodology developed by the Soil Conservation Service in the hydrologic model TR-55. This method divides the flow in three components: “sheet”, "shallow" and “channel” flow. The travel times for each component are determined and added, obtaining therefore a total time of concentration. The total time of concentration computation for the watersheds for both existing and proposed conditions are presented here

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Existing Conditions: AREA: CONDITION:

A EXISTING SEGMENT ID

SHEET FLOW

1. Surface description (table 3-1)………………………………………………………………… 2. Manning's roughness coeff., n (table 3-1)…..… ….…...……….………………………….. 3. Flow length, L (total L <= 300 ft)………………..……………………..…………..…….…ft 4. Two - yr 24-hr rainfall, P2……………………………………………………….…………..in 5. Land slope, s………………………………………………………………………….….…ft/ft 0.8 0.007 (nL) 6. Tt = Compute Tt……........……hr

1 Dense Brush 0.8 300 4.69 0.026 1.119

P20.5 * s0.4 SEGMENT ID SHALLOW CONCENTRATED FLOW 7. Surface description (paved or unpaved)……………………………………………………… 8. Flow length, L……………………………………………..………………….….…………….ft 9. W atercourse slope, s ………………………………………………………………….……ft/ft 10.Average velocity, V (figure 3-1) ….…….…………………………………………………ft/s 11. Tt = ____L____ Compute Tt…..….…....….hr 3600 V SEGMENT ID CHANNEL FLOW

12.Cross sectional flow area, a……………………………………………………..….…….ft^2 13. Wetted perimeter, Pw…………………………………………………………….……….ft 14. Hydraulic radius, r = a / Pw Compute r…..…......…….…ft 15. Channel slope, s…………………………………………………………………………..ft/ft 16. Manning's roughness coeff., n………….……………………..……..…………………….. 17. V= 1.49 r2/3 s1/2 Compute V….….…..…..ft/s n 18.Flow length, L………...…….………………….………………………………..…………..ft 19. Tt = ____L____ Compute Tt.…..…..…….hr 3600 V 20. Watershed or subarea Tc or Tt (add Tt in steps 6,11,and 19)…...……...…….….…hr Lag Time = 0.6 Tc =

2 unpaved 1751.52 0.001 1.20 0.405 3 0 0 0.000 0.0000 0 0.00 0.00 0.0000 1.525 0.915

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AREA: CONDITION:

B EXISTING SEGMENT ID

SHEET FLOW

1. Surface description (table 3-1)………………………………………………………………… 2. Manning's roughness coeff., n (table 3-1)…..… ….…...……….………………………….. 3. Flow length, L (total L <= 300 ft)………………..……………………..…………..…….…ft 4. Two - yr 24-hr rainfall, P2……………………………………………………….…………..in 5. Land slope, s………………………………………………………………………….….…ft/ft 0.007 (nL)0.8 6. Tt = Compute Tt……........……hr

1 Dense Brush 0.8 300 4.69 0.021 1.218

P20.5 * s0.4 SEGMENT ID SHALLOW CONCENTRATED FLOW 7. Surface description (paved or unpaved)……………………………………………………… 8. Flow length, L……………………………………………..………………….….…………….ft 9. W atercourse slope, s ………………………………………………………………….……ft/ft 10.Average velocity, V (figure 3-1) ….…….…………………………………………………ft/s 11. Tt = ____L____ Compute Tt…..….…....….hr 3600 V SEGMENT ID CHANNEL FLOW

12.Cross sectional flow area, a……………………………………………………..….…….ft^2 13. Wetted perimeter, Pw…………………………………………………………….……….ft 14. Hydraulic radius, r = a / Pw Compute r…..…......…….…ft 15. Channel slope, s…………………………………………………………………………..ft/ft 16. Manning's roughness coeff., n………….……………………..……..…………………….. 17. V= 1.49 r2/3 s1/2 Compute V….….…..…..ft/s n 18.Flow length, L………...…….………………….………………………………..…………..ft 19. Tt = ____L____ Compute Tt.…..…..…….hr 3600 V 20. Watershed or subarea Tc or Tt (add Tt in steps 6,11,and 19)…...……...…….….…hr Lag Time = 0.6 Tc =

2 unpaved 1760.08 0.001 1.20 0.407 3 0 0 0.000 0.0000 0 0.00 0.00 0.0000 1.626 0.976

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Proposed Conditions: AREA: CONDITION:

A PROPOSED SEGMENT ID

SHEET FLOW

1. Surface description (table 3-1)………………………………………………………………… 2. Manning's roughness coeff., n (table 3-1)…..… ….…...……….………………………….. 3. Flow length, L (total L <= 300 ft)………………..……………………..…………..…….…ft 4. Two - yr 24-hr rainfall, P2……………………………………………………….…………..in 5. Land slope, s………………………………………………………………………….….…ft/ft 0.007 (nL)0.8 6. Tt = Compute Tt……........……hr

1 Smoooth Surf. 0.011 300 4.69 0.020 0.040

P20.5 * s0.4 SEGMENT ID SHALLOW CONCENTRATED FLOW 7. Surface description (paved or unpaved)……………………………………………………… 8. Flow length, L……………………………………………..………………….….…………….ft 9. W atercourse slope, s ………………………………………………………………….……ft/ft 10.Average velocity, V (figure 3-1) ….…….…………………………………………………ft/s 11. Tt = ____L____ Compute Tt…..….…....….hr 3600 V SEGMENT ID CHANNEL FLOW

2 paved 815.34 0.001 1.50 0.151

12.Cross sectional flow area, a……………………………………………………..….…….ft^2 13. Wetted perimeter, Pw…………………………………………………………….……….ft 14. Hydraulic radius, r = a / Pw Compute r…..…......…….…ft 15. Channel slope, s…………………………………………………………………………..ft/ft 16. Manning's roughness coeff., n………….……………………..……..…………………….. 17. V= 1.49 r2/3 s1/2 Compute V….….…..…..ft/s n 18.Flow length, L………...…….………………….………………………………..…………..ft 19. Tt = ____L____ Compute Tt.…..…..…….hr 3600 V 20. Watershed or subarea Tc or Tt (add Tt in steps 6,11,and 19)…...……...…….….…hr

0 0 0.000 0.0000 0

Lag Time = 0.6 Tc =

3

0.00 0.00 0.0000 0.191 0.115

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AREA: CONDITION:

B PROPOSED SEGMENT ID

SHEET FLOW

1 Smoooth Surf. 0.011 300 4.69 0.006

1. Surface description (table 3-1)………………………………………………………………… 2. Manning's roughness coeff., n (table 3-1)…..… ….…...……….………………………….. 3. Flow length, L (total L <= 300 ft)………………..……………………..…………..…….…ft 4. Two - yr 24-hr rainfall, P2……………………………………………………….…………..in 5. Land slope, s………………………………………………………………………….….…ft/ft 0.007 (nL)0.8 6. Tt = Compute Tt……........……hr

0.067

P20.5 * s0.4 SEGMENT ID SHALLOW CONCENTRATED FLOW 7. Surface description (paved or unpaved)……………………………………………………… 8. Flow length, L……………………………………………..………………….….…………….ft 9. W atercourse slope, s ………………………………………………………………….……ft/ft 10.Average velocity, V (figure 3-1) ….…….…………………………………………………ft/s 11. Tt = ____L____ Compute Tt…..….…....….hr 3600 V SEGMENT ID CHANNEL FLOW

2 paved 1513.03 0.006 1.60 0.263

12.Cross sectional flow area, a……………………………………………………..….…….ft^2 13. Wetted perimeter, Pw…………………………………………………………….……….ft 14. Hydraulic radius, r = a / Pw Compute r…..…......…….…ft 15. Channel slope, s…………………………………………………………………………..ft/ft 16. Manning's roughness coeff., n………….……………………..……..…………………….. 17. V= 1.49 r2/3 s1/2 Compute V….….…..…..ft/s n 18.Flow length, L………...…….………………….………………………………..…………..ft 19. Tt = ____L____ Compute Tt.…..…..…….hr 3600 V 20. Watershed or subarea Tc or Tt (add Tt in steps 6,11,and 19)…...……...…….….…hr

0 0 0.000 0.0000 0

3

0.00 0.00 0.0000 0.329

Lag Time = 0.6 Tc =

0.198

STORM EVENTS Information concerning temporal and area distribution and frequencies, as well as depths of precipitation for Puerto Rico, has been compiled by the National Weather Service, U.S. Department of Commerce, in cooperation with the National Oceanic and Atmospheric Administration (NOAA) with the results published as NOAA Atlas 14. Twenty-four (24) hours storm events, with a frequency of 2, 5, 10, 25, 50 and 100 years were selected (Figure 6). The obtained values from the Atlas 14 are:

24 hrs. Precipitation (inches)

2 yrs. 4.69

5 yrs. 6.25

10 yrs. 7.49

25 yrs. 9.19

50 yrs. 10.6

100 yrs. 11.9

HYDROLOGIC MODEL To determine the maximum discharge for each watersehd produced by the different storm events, the computational model HydroCAD, was used as developed by the HydroCAD Software. This model analyze an hydrological system and determine the hydro gram of such, using the method to compute the runoff defined by the U.S. Soil Conservation Service in the NEH-4, taking in consideration the characteristics of the watershed like: area size, time of concentration, Curve Number and the precipitation

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caused by the storm event. To define the distribution of the precipitation during time, was used a synthetic distribution type II, the one suggested to use in Puerto Rico. The computational model determines the hydrograms for the watershed to obtain the maximum discharge and the time in which this occurs since the beginning of the event. The maximum discharges were determined for both existing and porposed conditions: EXISTING CONDITIONS Watershed “A” Peak Discharge (cfs)

2 years 37.63

5 years 62.65

10 years 77.33

25 years 97.34

50 years 113.86

100 years 129.03

2 years 154.96

5 years 209.53

10 years 252.65

25 years 311.55

50 years 360.28

100 years 405.14

2 years 55.06

5 years 78.06

10 years 96.26

25 years 121.08

50 years 141.55

100 years 160.35

2 years 183.89

5 years 247.69

10 years 298.18

25 years 367.19

50 years 424.31

100 years 476.92

PROPOSED CONDITIONS Watershed “A” Peak Discharge (cfs)

EXISTING CONDITIONS Watershed “B” Peak Discharge (cfs)

PROPOSED CONDITIONS Watershed “B” Peak Discharge (cfs)

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STORMWATER MITIGATION Due to the increase in runoff discharge produced by the proposed development, it is required to provide stormwater mitigation. The mitigation is needed in order to maintain a runoff at the discharge point that cannot exceeds the discharge produced by the existing conditions This can be accomplished by the implementation of a detention system that stores any increase in runoff volume and controls the discharge by means of an outlet hydraulic structure. An analysis was performed with the HydroCad model, by locating a detention structure before the discharge point of each watershed; that shall collect all the stormwater by means of a collection system to be considered on the design phase. The modeled detention system consists in a series of underground interconnected concrete box culverts, with an hydraulic control consisting of a orifice and culvert, that will finally convey the runoff into the existing conditions discharge point. From the analyses it was determined that the proposed discharges for the different storm events were reduced to pre-develpoment values. Watershed “A” PROPOSED CONDITIONS AFTER MITIGATION 2 years 5 years 10 years Watershed “A” Peak Discharge (cfs) 9.66 13.59 16.05

25 years

50 years

18.95

21.28

100 years

80.81

The proposed system has the following characteristics: Detention Structure: Reinforced Concreet Bos Culverts,(CONTECH Conspan or similar) Units: 900 units (14’ clear span x 7’ clear rise x 8’ long Each) System Dimensions: 30 Chambers/Row x 8.00' Long = 240.00' Base Length 30 Rows x 184.0" Wide + 4.0" Spacing x 29 + 0.0" Side Stone x 2 = 469.57' Base Width 6.0" Base + 92.0" Chamber Height = 8.17' Field Height 900 Chambers x 733.6 cf = 660,227.4 cf Chamber Storage Bottom Elevation = 5.00 ft=1.52 m Outlet Structure: 18” diameter PVC Pipe, slope S=0.010 Invert Elevation=5.00 ft=1.52m

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Watershed “B” PROPOSED CONDITIONS AFTER MITIGATION 2 years 5 years 10 years Watershed “B” Peak Discharge (cfs) 9.66 13.59 16.05

25 years

50 years

18.95

21.28

100 years

80.81

The proposed system has the following characteristics: Detention Structure: Reinforced Concreet Bos Culverts,(CONTECH Conspan or similar) Units: 900 units (14’ clear span x 7’ clear rise x 8’ long Each) System Dimensions: 30 Chambers/Row x 8.00' Long = 240.00' Base Length 30 Rows x 184.0" Wide + 4.0" Spacing x 29 + 0.0" Side Stone x 2 = 469.57' Base Width 6.0" Base + 92.0" Chamber Height = 8.17' Field Height 900 Chambers x 733.6 cf = 660,227.4 cf Chamber Storage Bottom Elevation = 5.00 ft=1.52 m Outlet Structure: 18” diameter PVC Pipe, slope S=0.010 Invert Elevation=5.00 ft=1.52m

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CONCLUSIONS AND RECOMMENDATIONS The proposed development will produce an increase in stormwater runoff volumes, when compared to existing pre-development conditions. For this reason it is necessary to provide an stormwater mitigation system that reduces the proposed runoff to predevelopment conditions as required by regulations. The proposed stormwater system will consist of a detention structure conformed by a series of underground concrete box culverts with a controlled discharge outlet structure. The existing discharge points will remain. For watershed “A” the discharge will be maintained to an existing headwall and pipe system next to Kennedy Avenue. For watershed ”B”, the discharge point will be the Bechara Channel. The proposed conditions will not have adverse effects on the existing water bodies and will prevent any flood conditions downstream of the project due to any increase in runoff volume. A proper maintenance schedule must be enforced in order to prevent the accumulation of debris at the detention structure as well as at the outlet and discharge points, that can reduce the storage capacity. The results and recommendations presented on this report are based exclusively on the available data at the time of this report for the “Mercado Central” Development. The most adequate resources and methodology have been used in the preparation of the hydraulic and hydrologic calculations. All recommendations must be implemented on the construction plans related to the project. Any project modifications will change the results and conclusions presented here

Dwight Rodriguez, P.E., M.C.E. Lic. 15500

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REFERENCES

McCuen, Richard H. Hydrologic Analysis and Design. 2nd ed., Prentice Hall Inc., 1998. Gupta, R.S. Hydrology and Hydraulic Systems. 2nd ed., Prentice Hall Inc., 2001. U.S. Department of Commerce. NOAA Weather Bureau Atlas 14: ”Generalized Estimates of Probable Maximum Precipitation and Rainfall-Frequency Data for Puerto Rico and Virgin Islands”, 1962. U.S. Department of Agriculture. Soil conservation Service, Engineering Division. TR-55 Manual: Urban Hydrology for Small Watersheds, 1986.

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APPENDIX 1 FIGURES

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APPENDIX 2 (EXISTING CONDITIONS HYDROCAD REPORT)

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Existing Conditions Mercado Central Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Area Listing (all nodes) Area (acres)

CN

67.920 2.770 70.690

89 93

Description (subcatchment-numbers) Hy, Saline, Herbaceous fair condition (A, B) Hy, Saline, Herbaceous poor condition (A, B) TOTAL AREA

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Existing Conditions Mercado Central Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Soil Listing (all nodes) Area (acres)

Soil Group

0.000 0.000 0.000 0.000 70.690 70.690

HSG A HSG B HSG C HSG D Other

Subcatchment Numbers

A, B TOTAL AREA

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Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69"

Existing Conditions Mercado Central

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Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment A: Area "A" Runoff

=

37.63 cfs @ 13.00 hrs, Volume=

7.911 af, Depth> 3.40"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69" CN 89 93 89

Description Hy, Saline, Herbaceous fair condition Hy, Saline, Herbaceous poor condition Weighted Average 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 67.0 300 0.0260 0.07 Sheet Flow, Woods: Dense underbrush n= 0.800 P2= 4.69" 24.5 1,752 0.0055 1.19 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 91.5 2,052 Total

Subcatchment A: Area "A" Hydrograph 42 40

Runoff

37.63 cfs

38 36

Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69" Runoff Area=27.880 ac Runoff Volume=7.911 af Runoff Depth>3.40" Flow Length=2,052' Tc=91.5 min CN=89

34 32 30 28 26 Flow (cfs)

* *

Area (ac) 26.260 1.620 27.880 27.880

24 22 20 18 16 14 12 10 8 6 4 2 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 Time (hours)

14

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69"

Existing Conditions Mercado Central

Printed 7/19/2012 Page 4

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment B: Area "B" Runoff

=

55.06 cfs @ 13.09 hrs, Volume=

12.130 af, Depth> 3.40"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69" CN 89 93 89

Description Hy, Saline, Herbaceous fair condition Hy, Saline, Herbaceous poor condition Weighted Average 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 72.9 300 0.0210 0.07 Sheet Flow, Woods: Dense underbrush n= 0.800 P2= 4.69" 24.6 1,760 0.0055 1.19 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 97.5 2,060 Total

Subcatchment B: Area "B" Hydrograph 60 Runoff

55.06 cfs 55

Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69" Runoff Area=42.810 ac Runoff Volume=12.130 af Runoff Depth>3.40" Flow Length=2,060' Tc=97.5 min CN=89

50 45 40 Flow (cfs)

* *

Area (ac) 41.660 1.150 42.810 42.810

35 30 25 20 15 10 5 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 Time (hours)

14

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25"

Existing Conditions Mercado Central

Printed 7/19/2012 Page 5

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment A: Area "A" Runoff

=

53.35 cfs @ 12.99 hrs, Volume=

11.342 af, Depth> 4.88"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25" CN 89 93 89

Description Hy, Saline, Herbaceous fair condition Hy, Saline, Herbaceous poor condition Weighted Average 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 67.0 300 0.0260 0.07 Sheet Flow, Woods: Dense underbrush n= 0.800 P2= 4.69" 24.5 1,752 0.0055 1.19 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 91.5 2,052 Total

Subcatchment A: Area "A" Hydrograph Runoff

53.35 cfs

55

Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25" Runoff Area=27.880 ac Runoff Volume=11.342 af Runoff Depth>4.88" Flow Length=2,052' Tc=91.5 min CN=89

50 45 40 Flow (cfs)

* *

Area (ac) 26.260 1.620 27.880 27.880

35 30 25 20 15 10 5 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 Time (hours)

14

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25"

Existing Conditions Mercado Central

Printed 7/19/2012 Page 6

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment B: Area "B" Runoff

=

78.06 cfs @ 13.09 hrs, Volume=

17.391 af, Depth> 4.87"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25" CN 89 93 89

Description Hy, Saline, Herbaceous fair condition Hy, Saline, Herbaceous poor condition Weighted Average 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 72.9 300 0.0210 0.07 Sheet Flow, Woods: Dense underbrush n= 0.800 P2= 4.69" 24.6 1,760 0.0055 1.19 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 97.5 2,060 Total

Subcatchment B: Area "B" Hydrograph 85 Runoff

78.06 cfs

80 75

Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25" Runoff Area=42.810 ac Runoff Volume=17.391 af Runoff Depth>4.87" Flow Length=2,060' Tc=97.5 min CN=89

70 65 60 55 Flow (cfs)

* *

Area (ac) 41.660 1.150 42.810 42.810

50 45 40 35 30 25 20 15 10 5 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 Time (hours)

14

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49"

Existing Conditions Mercado Central

Printed 7/19/2012 Page 7

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment A: Area "A" Runoff

=

65.80 cfs @ 12.99 hrs, Volume=

14.104 af, Depth> 6.07"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49" CN 89 93 89

Description Hy, Saline, Herbaceous fair condition Hy, Saline, Herbaceous poor condition Weighted Average 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 67.0 300 0.0260 0.07 Sheet Flow, Woods: Dense underbrush n= 0.800 P2= 4.69" 24.5 1,752 0.0055 1.19 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 91.5 2,052 Total

Subcatchment A: Area "A" Hydrograph 70

Runoff

65.80 cfs

65

Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49" Runoff Area=27.880 ac Runoff Volume=14.104 af Runoff Depth>6.07" Flow Length=2,052' Tc=91.5 min CN=89

60 55 50 45 Flow (cfs)

* *

Area (ac) 26.260 1.620 27.880 27.880

40 35 30 25 20 15 10 5 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 Time (hours)

14

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49"

Existing Conditions Mercado Central

Printed 7/19/2012 Page 8

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment B: Area "B" Runoff

=

96.26 cfs @ 13.09 hrs, Volume=

21.628 af, Depth> 6.06"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49" CN 89 93 89

Description Hy, Saline, Herbaceous fair condition Hy, Saline, Herbaceous poor condition Weighted Average 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 72.9 300 0.0210 0.07 Sheet Flow, Woods: Dense underbrush n= 0.800 P2= 4.69" 24.6 1,760 0.0055 1.19 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 97.5 2,060 Total

Subcatchment B: Area "B" Hydrograph 105 Runoff

96.26 cfs

100 95

Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49" Runoff Area=42.810 ac Runoff Volume=21.628 af Runoff Depth>6.06" Flow Length=2,060' Tc=97.5 min CN=89

90 85 80 75

Flow (cfs)

* *

Area (ac) 41.660 1.150 42.810 42.810

70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19"

Existing Conditions Mercado Central

Printed 7/19/2012 Page 9

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment A: Area "A" Runoff

=

82.77 cfs @ 12.98 hrs, Volume=

17.920 af, Depth> 7.71"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19" CN 89 93 89

Description Hy, Saline, Herbaceous fair condition Hy, Saline, Herbaceous poor condition Weighted Average 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 67.0 300 0.0260 0.07 Sheet Flow, Woods: Dense underbrush n= 0.800 P2= 4.69" 24.5 1,752 0.0055 1.19 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 91.5 2,052 Total

Subcatchment A: Area "A" Hydrograph 90 Runoff

82.77 cfs

85 80

Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19" Runoff Area=27.880 ac Runoff Volume=17.920 af Runoff Depth>7.71" Flow Length=2,052' Tc=91.5 min CN=89

75 70 65 60 Flow (cfs)

* *

Area (ac) 26.260 1.620 27.880 27.880

55 50 45 40 35 30 25 20 15 10 5 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 Time (hours)

14

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19"

Existing Conditions Mercado Central

Printed 7/19/2012 Page 10

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment B: Area "B" Runoff

=

121.08 cfs @ 13.08 hrs, Volume=

27.481 af, Depth> 7.70"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19" CN 89 93 89

Description Hy, Saline, Herbaceous fair condition Hy, Saline, Herbaceous poor condition Weighted Average 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 72.9 300 0.0210 0.07 Sheet Flow, Woods: Dense underbrush n= 0.800 P2= 4.69" 24.6 1,760 0.0055 1.19 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 97.5 2,060 Total

Subcatchment B: Area "B" Hydrograph

Flow (cfs)

* *

Area (ac) 41.660 1.150 42.810 42.810

135 130 125 120 115 110 105 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0

Runoff

121.08 cfs

Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19" Runoff Area=42.810 ac Runoff Volume=27.481 af Runoff Depth>7.70" Flow Length=2,060' Tc=97.5 min CN=89

0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60"

Existing Conditions Mercado Central

Printed 7/19/2012 Page 11

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment A: Area "A" Runoff

=

96.76 cfs @ 12.98 hrs, Volume=

21.101 af, Depth> 9.08"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60" CN 89 93 89

Description Hy, Saline, Herbaceous fair condition Hy, Saline, Herbaceous poor condition Weighted Average 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 67.0 300 0.0260 0.07 Sheet Flow, Woods: Dense underbrush n= 0.800 P2= 4.69" 24.5 1,752 0.0055 1.19 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 91.5 2,052 Total

Subcatchment A: Area "A" Hydrograph 105 100

Runoff

96.76 cfs

95 90

Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60" Runoff Area=27.880 ac Runoff Volume=21.101 af Runoff Depth>9.08" Flow Length=2,052' Tc=91.5 min CN=89

85 80 75

Flow (cfs)

* *

Area (ac) 26.260 1.620 27.880 27.880

70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60"

Existing Conditions Mercado Central

Printed 7/19/2012 Page 12

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment B: Area "B" Runoff

=

141.55 cfs @ 13.08 hrs, Volume=

32.360 af, Depth> 9.07"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60" CN 89 93 89

Description Hy, Saline, Herbaceous fair condition Hy, Saline, Herbaceous poor condition Weighted Average 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 72.9 300 0.0210 0.07 Sheet Flow, Woods: Dense underbrush n= 0.800 P2= 4.69" 24.6 1,760 0.0055 1.19 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 97.5 2,060 Total

Subcatchment B: Area "B" Hydrograph 150

Runoff

141.55 cfs

140

Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60" Runoff Area=42.810 ac Runoff Volume=32.360 af Runoff Depth>9.07" Flow Length=2,060' Tc=97.5 min CN=89

130 120 110 100 Flow (cfs)

* *

Area (ac) 41.660 1.150 42.810 42.810

90 80 70 60 50 40 30 20 10 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90"

Existing Conditions Mercado Central

Printed 7/19/2012 Page 13

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment A: Area "A" Runoff

=

109.62 cfs @ 12.98 hrs, Volume=

24.042 af, Depth>10.35"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90" CN 89 93 89

Description Hy, Saline, Herbaceous fair condition Hy, Saline, Herbaceous poor condition Weighted Average 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 67.0 300 0.0260 0.07 Sheet Flow, Woods: Dense underbrush n= 0.800 P2= 4.69" 24.5 1,752 0.0055 1.19 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 91.5 2,052 Total

Subcatchment A: Area "A" Hydrograph

Flow (cfs)

* *

Area (ac) 26.260 1.620 27.880 27.880

120 115 110 105 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0

Runoff

109.62 cfs

Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90" Runoff Area=27.880 ac Runoff Volume=24.042 af Runoff Depth>10.35" Flow Length=2,052' Tc=91.5 min CN=89

0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90"

Existing Conditions Mercado Central

Printed 7/19/2012 Page 14

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment B: Area "B" Runoff

=

160.35 cfs @ 13.08 hrs, Volume=

36.871 af, Depth>10.34"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90" CN 89 93 89

Description Hy, Saline, Herbaceous fair condition Hy, Saline, Herbaceous poor condition Weighted Average 100.00% Pervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 72.9 300 0.0210 0.07 Sheet Flow, Woods: Dense underbrush n= 0.800 P2= 4.69" 24.6 1,760 0.0055 1.19 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 97.5 2,060 Total

Subcatchment B: Area "B" Hydrograph 170

Runoff

160.35 cfs

160

Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90" Runoff Area=42.810 ac Runoff Volume=36.871 af Runoff Depth>10.34" Flow Length=2,060' Tc=97.5 min CN=89

150 140 130 120 110 Flow (cfs)

* *

Area (ac) 41.660 1.150 42.810 42.810

100 90 80 70 60 50 40 30 20 10 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


APPENDIX 3 (PROPOSED CONDITIONS HYDROCAD REPORT)


Proposed Conditions Mercado Central Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Area Listing (all nodes) Area (acres)

CN

12.990 35.810 22.850 71.650

85 98 98

Description (subcatchment-numbers) Hy, Saline, Herbaceous good condition (A, B) Hy, Saline, Paved (B) Hy, Saline, paved areas (A) TOTAL AREA

Printed 7/19/2012 Page 1


Proposed Conditions Mercado Central Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Soil Listing (all nodes) Area (acres)

Soil Group

0.000 0.000 0.000 0.000 71.650 71.650

HSG A HSG B HSG C HSG D Other

Subcatchment Numbers

A, B TOTAL AREA

Printed 7/19/2012 Page 2


Proposed Conditions Mercado Central Printed 7/19/2012 Page 3

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Pipe Listing (all nodes) Line# 1

Node Number 3P

In-Invert (feet)

Out-Invert (feet)

Length (feet)

Slope (ft/ft)

n

Diam/Width (inches)

Height (inches)

Fill (inches)

5.00

5.00

100.0

0.0000

0.010

18.0

0.0

0.0


Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 4

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment A: Area "A" Runoff

=

154.96 cfs @ 12.02 hrs, Volume=

9.865 af, Depth> 4.10"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69" CN 85 98 95

Description Hy, Saline, Herbaceous good condition Hy, Saline, paved areas Weighted Average 20.77% Pervious Area 79.23% Impervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.4 300 0.0200 2.07 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.69" 9.0 815 0.0055 1.51 Shallow Concentrated Flow, Paved Kv= 20.3 fps 11.4 1,115 Total

Subcatchment A: Area "A" Hydrograph 170 Runoff

154.96 cfs

160 150

Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69" Runoff Area=28.840 ac Runoff Volume=9.865 af Runoff Depth>4.10" Flow Length=1,115' Tc=11.4 min CN=95

140 130 120 110 Flow (cfs)

* *

Area (ac) 5.990 22.850 28.840 5.990 22.850

100 90 80 70 60 50 40 30 20 10 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 5

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment B: Area "B" Runoff

=

185.36 cfs @ 12.11 hrs, Volume=

15.020 af, Depth> 4.21"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69" CN 85 98 96

Description Hy, Saline, Herbaceous good condition Hy, Saline, Paved Weighted Average 16.35% Pervious Area 83.65% Impervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 3.9 300 0.0060 1.28 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.69" 15.7 1,513 0.0063 1.61 Shallow Concentrated Flow, Paved Kv= 20.3 fps 19.6 1,813 Total

Subcatchment B: Area "B" Hydrograph 200

Runoff

185.36 cfs

190 180

Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69" Runoff Area=42.810 ac Runoff Volume=15.020 af Runoff Depth>4.21" Flow Length=1,813' Tc=19.6 min CN=96

170 160 150 140 130 Flow (cfs)

* *

Area (ac) 7.000 35.810 42.810 7.000 35.810

120 110 100 90 80 70 60 50 40 30 20 10 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 6

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Pond 2P: (new Pond) Inflow Area = Inflow = Primary =

42.810 ac, 83.65% Impervious, Inflow Depth > 4.21" for 2 yrs. 24 hrs. event 185.36 cfs @ 12.11 hrs, Volume= 15.020 af 185.36 cfs @ 12.11 hrs, Volume= 15.020 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs

Pond 2P: (new Pond) Hydrograph 200

Inflow Primary

185.36 cfs

190 180

Inflow Area=42.810 ac

170 160 150 140 Flow (cfs)

130 120 110 100 90 80 70 60 50 40 30 20 10 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Proposed Conditions Mercado Central

Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69"

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Printed 7/19/2012 Page 7

Summary for Pond 3P: STORAGE A Inflow Area = Inflow = Outflow = Primary =

28.840 ac, 79.23% Impervious, Inflow Depth > 4.10" for 2 yrs. 24 hrs. event 154.96 cfs @ 12.02 hrs, Volume= 9.865 af 9.66 cfs @ 12.96 hrs, Volume= 6.573 af, Atten= 94%, Lag= 56.4 min 9.66 cfs @ 12.96 hrs, Volume= 6.573 af

Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 7.51' @ 12.96 hrs Surf.Area= 2.587 ac Storage= 6.375 af Plug-Flow detention time= 340.3 min calculated for 6.559 af (66% of inflow) Center-of-Mass det. time= 243.4 min ( 1,013.5 - 770.1 ) Volume #1A #2A

Invert 5.00'

Avail.Storage 15.157 af

4.50'

1.117 af 16.274 af

Storage Description CONSPAN 14x 7 x 900 Inside #2 Inside= 168.0"W x 84.0"H => 91.70 sf x 8.00'L = 733.6 cf Outside= 184.0"W x 92.0"H => 110.98 sf x 8.00'L = 887.8 cf 469.57'W x 240.00'L x 8.17'H Field A 21.137 af Overall - 18.344 af Embedded = 2.793 af x 40.0% Voids Total Available Storage

Storage Group A created with Chamber Wizard Device #1

Routing Primary

Invert 5.00'

Outlet Devices 18.0" Round Culvert L= 100.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 5.00' / 5.00' S= 0.0000 '/' Cc= 0.900 n= 0.010 PVC, smooth interior

Primary OutFlow Max=9.66 cfs @ 12.96 hrs HW=7.51' (Free Discharge) 1=Culvert (Barrel Controls 9.66 cfs @ 5.47 fps)


Type II 24-hr 2 yrs. 24 hrs. Rainfall=4.69"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 8

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Pond 3P: STORAGE A Hydrograph 170

150

Inflow Area=28.840 ac Peak Elev=7.51' Storage=6.375 af 18.0" Round Culvert n=0.010 L=100.0' S=0.0000 '/'

140 130 120 110 Flow (cfs)

Inflow Primary

154.96 cfs

160

100 90 80 70 60 50 40 30 20

9.66 cfs

10 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

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18

19

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23

24


Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 9

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment A: Area "A" Runoff

=

209.53 cfs @ 12.02 hrs, Volume=

13.578 af, Depth> 5.65"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25" CN 85 98 95

Description Hy, Saline, Herbaceous good condition Hy, Saline, paved areas Weighted Average 20.77% Pervious Area 79.23% Impervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.4 300 0.0200 2.07 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.69" 9.0 815 0.0055 1.51 Shallow Concentrated Flow, Paved Kv= 20.3 fps 11.4 1,115 Total

Subcatchment A: Area "A" Hydrograph

Flow (cfs)

* *

Area (ac) 5.990 22.850 28.840 5.990 22.850

230 220 210 200 190 180 170 160 150 140 130 120 110 100 90 80 70 60 50 40 30 20 10 0

Runoff

209.53 cfs

Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25" Runoff Area=28.840 ac Runoff Volume=13.578 af Runoff Depth>5.65" Flow Length=1,115' Tc=11.4 min CN=95

0

1

2

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11 12 13 14 Time (hours)

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19

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23

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Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 10

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment B: Area "B" Runoff

=

249.67 cfs @ 12.11 hrs, Volume=

20.539 af, Depth> 5.76"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25" CN 85 98 96

Description Hy, Saline, Herbaceous good condition Hy, Saline, Paved Weighted Average 16.35% Pervious Area 83.65% Impervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 3.9 300 0.0060 1.28 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.69" 15.7 1,513 0.0063 1.61 Shallow Concentrated Flow, Paved Kv= 20.3 fps 19.6 1,813 Total

Subcatchment B: Area "B" Hydrograph Runoff

249.67 cfs

260 240

Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25" Runoff Area=42.810 ac Runoff Volume=20.539 af Runoff Depth>5.76" Flow Length=1,813' Tc=19.6 min CN=96

220 200 180 Flow (cfs)

* *

Area (ac) 7.000 35.810 42.810 7.000 35.810

160 140 120 100 80 60 40 20 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 11

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Pond 2P: (new Pond) Inflow Area = Inflow = Primary =

42.810 ac, 83.65% Impervious, Inflow Depth > 5.76" for 5 yrs. 24 hrs. event 249.67 cfs @ 12.11 hrs, Volume= 20.539 af 249.67 cfs @ 12.11 hrs, Volume= 20.539 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs

Pond 2P: (new Pond) Hydrograph Inflow Primary

249.67 cfs

260 240

Inflow Area=42.810 ac

220 200

Flow (cfs)

180 160 140 120 100 80 60 40 20 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Proposed Conditions Mercado Central

Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25"

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Printed 7/19/2012 Page 12

Summary for Pond 3P: STORAGE A Inflow Area = Inflow = Outflow = Primary =

28.840 ac, 79.23% Impervious, Inflow Depth > 5.65" for 5 yrs. 24 hrs. event 209.53 cfs @ 12.02 hrs, Volume= 13.578 af 13.59 cfs @ 12.90 hrs, Volume= 9.585 af, Atten= 94%, Lag= 52.7 min 13.59 cfs @ 12.90 hrs, Volume= 9.585 af

Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 8.50' @ 12.90 hrs Surf.Area= 2.587 ac Storage= 8.679 af Plug-Flow detention time= 338.7 min calculated for 9.565 af (70% of inflow) Center-of-Mass det. time= 245.7 min ( 1,008.4 - 762.6 ) Volume #1A #2A

Invert 5.00'

Avail.Storage 15.157 af

4.50'

1.117 af 16.274 af

Storage Description CONSPAN 14x 7 x 900 Inside #2 Inside= 168.0"W x 84.0"H => 91.70 sf x 8.00'L = 733.6 cf Outside= 184.0"W x 92.0"H => 110.98 sf x 8.00'L = 887.8 cf 469.57'W x 240.00'L x 8.17'H Field A 21.137 af Overall - 18.344 af Embedded = 2.793 af x 40.0% Voids Total Available Storage

Storage Group A created with Chamber Wizard Device #1

Routing Primary

Invert 5.00'

Outlet Devices 18.0" Round Culvert L= 100.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 5.00' / 5.00' S= 0.0000 '/' Cc= 0.900 n= 0.010 PVC, smooth interior

Primary OutFlow Max=13.59 cfs @ 12.90 hrs HW=8.50' (Free Discharge) 1=Culvert (Barrel Controls 13.59 cfs @ 7.69 fps)


Type II 24-hr 5 yrs. 24 hrs. Rainfall=6.25"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 13

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Pond 3P: STORAGE A

Flow (cfs)

Hydrograph 230 220 210 200 190 180 170 160 150 140 130 120 110 100 90 80 70 60 50 40 30 20 10 0

Inflow Primary

209.53 cfs

Inflow Area=28.840 ac Peak Elev=8.50' Storage=8.679 af 18.0" Round Culvert n=0.010 L=100.0' S=0.0000 '/' 13.59 cfs

0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

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16

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18

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23

24


Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 14

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment A: Area "A" Runoff

=

252.65 cfs @ 12.02 hrs, Volume=

16.537 af, Depth> 6.88"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49" CN 85 98 95

Description Hy, Saline, Herbaceous good condition Hy, Saline, paved areas Weighted Average 20.77% Pervious Area 79.23% Impervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.4 300 0.0200 2.07 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.69" 9.0 815 0.0055 1.51 Shallow Concentrated Flow, Paved Kv= 20.3 fps 11.4 1,115 Total

Subcatchment A: Area "A" Hydrograph 280 Runoff

252.65 cfs

260

Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49" Runoff Area=28.840 ac Runoff Volume=16.537 af Runoff Depth>6.88" Flow Length=1,115' Tc=11.4 min CN=95

240 220 200 180 Flow (cfs)

* *

Area (ac) 5.990 22.850 28.840 5.990 22.850

160 140 120 100 80 60 40 20 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 15

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment B: Area "B" Runoff

=

300.55 cfs @ 12.11 hrs, Volume=

24.934 af, Depth> 6.99"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49" CN 85 98 96

Description Hy, Saline, Herbaceous good condition Hy, Saline, Paved Weighted Average 16.35% Pervious Area 83.65% Impervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 3.9 300 0.0060 1.28 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.69" 15.7 1,513 0.0063 1.61 Shallow Concentrated Flow, Paved Kv= 20.3 fps 19.6 1,813 Total

Subcatchment B: Area "B" Hydrograph 320

Runoff

300.55 cfs

300

Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49" Runoff Area=42.810 ac Runoff Volume=24.934 af Runoff Depth>6.99" Flow Length=1,813' Tc=19.6 min CN=96

280 260 240 220 Flow (cfs)

* *

Area (ac) 7.000 35.810 42.810 7.000 35.810

200 180 160 140 120 100 80 60 40 20 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 16

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Pond 2P: (new Pond) Inflow Area = Inflow = Primary =

42.810 ac, 83.65% Impervious, Inflow Depth > 6.99" for 10 yrs. 24 hrs. event 300.55 cfs @ 12.11 hrs, Volume= 24.934 af 300.55 cfs @ 12.11 hrs, Volume= 24.934 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs

Pond 2P: (new Pond) Hydrograph 320

Inflow Primary

300.55 cfs

300

Inflow Area=42.810 ac

280 260 240

Flow (cfs)

220 200 180 160 140 120 100 80 60 40 20 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Proposed Conditions Mercado Central

Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49"

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Printed 7/19/2012 Page 17

Summary for Pond 3P: STORAGE A Inflow Area = Inflow = Outflow = Primary =

28.840 ac, 79.23% Impervious, Inflow Depth > 6.88" for 10 yrs. 24 hrs. event 252.65 cfs @ 12.02 hrs, Volume= 16.537 af 16.05 cfs @ 12.93 hrs, Volume= 11.893 af, Atten= 94%, Lag= 54.1 min 16.05 cfs @ 12.93 hrs, Volume= 11.893 af

Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 9.30' @ 12.93 hrs Surf.Area= 2.587 ac Storage= 10.515 af Plug-Flow detention time= 340.7 min calculated for 11.868 af (72% of inflow) Center-of-Mass det. time= 249.1 min ( 1,007.5 - 758.4 ) Volume #1A #2A

Invert 5.00'

Avail.Storage 15.157 af

4.50'

1.117 af 16.274 af

Storage Description CONSPAN 14x 7 x 900 Inside #2 Inside= 168.0"W x 84.0"H => 91.70 sf x 8.00'L = 733.6 cf Outside= 184.0"W x 92.0"H => 110.98 sf x 8.00'L = 887.8 cf 469.57'W x 240.00'L x 8.17'H Field A 21.137 af Overall - 18.344 af Embedded = 2.793 af x 40.0% Voids Total Available Storage

Storage Group A created with Chamber Wizard Device #1

Routing Primary

Invert 5.00'

Outlet Devices 18.0" Round Culvert L= 100.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 5.00' / 5.00' S= 0.0000 '/' Cc= 0.900 n= 0.010 PVC, smooth interior

Primary OutFlow Max=16.05 cfs @ 12.93 hrs HW=9.30' (Free Discharge) 1=Culvert (Barrel Controls 16.05 cfs @ 9.08 fps)


Type II 24-hr 10 yrs. 24 hrs. Rainfall=7.49"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 18

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Pond 3P: STORAGE A Hydrograph 280

Inflow Area=28.840 ac Peak Elev=9.30' Storage=10.515 af 18.0" Round Culvert n=0.010 L=100.0' S=0.0000 '/'

240 220 200 180 Flow (cfs)

Inflow Primary

252.65 cfs

260

160 140 120 100 80 60 40

16.05 cfs

20 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 19

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment A: Area "A" Runoff

=

311.55 cfs @ 12.02 hrs, Volume=

20.601 af, Depth> 8.57"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19" CN 85 98 95

Description Hy, Saline, Herbaceous good condition Hy, Saline, paved areas Weighted Average 20.77% Pervious Area 79.23% Impervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.4 300 0.0200 2.07 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.69" 9.0 815 0.0055 1.51 Shallow Concentrated Flow, Paved Kv= 20.3 fps 11.4 1,115 Total

Subcatchment A: Area "A" Hydrograph 340 Runoff

311.55 cfs

320 300

Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19" Runoff Area=28.840 ac Runoff Volume=20.601 af Runoff Depth>8.57" Flow Length=1,115' Tc=11.4 min CN=95

280 260 240 220 Flow (cfs)

* *

Area (ac) 5.990 22.850 28.840 5.990 22.850

200 180 160 140 120 100 80 60 40 20 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

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18

19

20

21

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23

24


Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 20

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment B: Area "B" Runoff

=

370.10 cfs @ 12.11 hrs, Volume=

30.966 af, Depth> 8.68"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19" CN 85 98 96

Description Hy, Saline, Herbaceous good condition Hy, Saline, Paved Weighted Average 16.35% Pervious Area 83.65% Impervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 3.9 300 0.0060 1.28 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.69" 15.7 1,513 0.0063 1.61 Shallow Concentrated Flow, Paved Kv= 20.3 fps 19.6 1,813 Total

Subcatchment B: Area "B" Hydrograph 400

Runoff

370.10 cfs

380 360

Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19" Runoff Area=42.810 ac Runoff Volume=30.966 af Runoff Depth>8.68" Flow Length=1,813' Tc=19.6 min CN=96

340 320 300 280 260 Flow (cfs)

* *

Area (ac) 7.000 35.810 42.810 7.000 35.810

240 220 200 180 160 140 120 100 80 60 40 20 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 21

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Pond 2P: (new Pond) Inflow Area = Inflow = Primary =

42.810 ac, 83.65% Impervious, Inflow Depth > 8.68" for 25 yrs. 24 hrs. event 370.10 cfs @ 12.11 hrs, Volume= 30.966 af 370.10 cfs @ 12.11 hrs, Volume= 30.966 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs

Pond 2P: (new Pond) Hydrograph 400

Inflow Primary

370.10 cfs

380 360

Inflow Area=42.810 ac

340 320 300 280

Flow (cfs)

260 240 220 200 180 160 140 120 100 80 60 40 20 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Proposed Conditions Mercado Central

Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19"

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Printed 7/19/2012 Page 22

Summary for Pond 3P: STORAGE A Inflow Area = Inflow = Outflow = Primary =

28.840 ac, 79.23% Impervious, Inflow Depth > 8.57" for 25 yrs. 24 hrs. event 311.55 cfs @ 12.02 hrs, Volume= 20.601 af 18.95 cfs @ 12.98 hrs, Volume= 15.002 af, Atten= 94%, Lag= 57.5 min 18.95 cfs @ 12.98 hrs, Volume= 15.002 af

Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 10.39' @ 12.98 hrs Surf.Area= 2.587 ac Storage= 13.022 af Plug-Flow detention time= 346.7 min calculated for 14.971 af (73% of inflow) Center-of-Mass det. time= 255.7 min ( 1,009.7 - 754.0 ) Volume #1A #2A

Invert 5.00'

Avail.Storage 15.157 af

4.50'

1.117 af 16.274 af

Storage Description CONSPAN 14x 7 x 900 Inside #2 Inside= 168.0"W x 84.0"H => 91.70 sf x 8.00'L = 733.6 cf Outside= 184.0"W x 92.0"H => 110.98 sf x 8.00'L = 887.8 cf 469.57'W x 240.00'L x 8.17'H Field A 21.137 af Overall - 18.344 af Embedded = 2.793 af x 40.0% Voids Total Available Storage

Storage Group A created with Chamber Wizard Device #1

Routing Primary

Invert 5.00'

Outlet Devices 18.0" Round Culvert L= 100.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 5.00' / 5.00' S= 0.0000 '/' Cc= 0.900 n= 0.010 PVC, smooth interior

Primary OutFlow Max=18.95 cfs @ 12.98 hrs HW=10.39' (Free Discharge) 1=Culvert (Barrel Controls 18.95 cfs @ 10.72 fps)


Type II 24-hr 25 yrs. 24 hrs. Rainfall=9.19"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 23

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Pond 3P: STORAGE A Hydrograph 340

300

Inflow Area=28.840 ac Peak Elev=10.39' Storage=13.022 af 18.0" Round Culvert n=0.010 L=100.0' S=0.0000 '/'

280 260 240 220 Flow (cfs)

Inflow Primary

311.55 cfs

320

200 180 160 140 120 100 80 60 40

18.95 cfs

20 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 24

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment A: Area "A" Runoff

=

360.28 cfs @ 12.02 hrs, Volume=

23.975 af, Depth> 9.98"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60" CN 85 98 95

Description Hy, Saline, Herbaceous good condition Hy, Saline, paved areas Weighted Average 20.77% Pervious Area 79.23% Impervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.4 300 0.0200 2.07 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.69" 9.0 815 0.0055 1.51 Shallow Concentrated Flow, Paved Kv= 20.3 fps 11.4 1,115 Total

Subcatchment A: Area "A" Hydrograph 400 380

Runoff

360.28 cfs

360

Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60" Runoff Area=28.840 ac Runoff Volume=23.975 af Runoff Depth>9.98" Flow Length=1,115' Tc=11.4 min CN=95

340 320 300 280 260 Flow (cfs)

* *

Area (ac) 5.990 22.850 28.840 5.990 22.850

240 220 200 180 160 140 120 100 80 60 40 20 0 0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 25

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment B: Area "B" Runoff

=

427.68 cfs @ 12.11 hrs, Volume=

35.972 af, Depth>10.08"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60" CN 85 98 96

Description Hy, Saline, Herbaceous good condition Hy, Saline, Paved Weighted Average 16.35% Pervious Area 83.65% Impervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 3.9 300 0.0060 1.28 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.69" 15.7 1,513 0.0063 1.61 Shallow Concentrated Flow, Paved Kv= 20.3 fps 19.6 1,813 Total

Subcatchment B: Area "B" Hydrograph

Flow (cfs)

* *

Area (ac) 7.000 35.810 42.810 7.000 35.810

460 440 420 400 380 360 340 320 300 280 260 240 220 200 180 160 140 120 100 80 60 40 20 0

Runoff

427.68 cfs

Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60" Runoff Area=42.810 ac Runoff Volume=35.972 af Runoff Depth>10.08" Flow Length=1,813' Tc=19.6 min CN=96

0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

17

18

19

20

21

22

23

24


Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 26

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Pond 2P: (new Pond) Inflow Area = Inflow = Primary =

42.810 ac, 83.65% Impervious, Inflow Depth > 10.08" for 50 yrs. 24 hrs. event 427.68 cfs @ 12.11 hrs, Volume= 35.972 af 427.68 cfs @ 12.11 hrs, Volume= 35.972 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs

Pond 2P: (new Pond)

Flow (cfs)

Hydrograph 460 440 420 400 380 360 340 320 300 280 260 240 220 200 180 160 140 120 100 80 60 40 20 0

Inflow Primary

427.68 cfs

Inflow Area=42.810 ac

0

1

2

3

4

5

6

7

8

9

10

11 12 13 14 Time (hours)

15

16

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Proposed Conditions Mercado Central

Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60"

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Printed 7/19/2012 Page 27

Summary for Pond 3P: STORAGE A Inflow Area = Inflow = Outflow = Primary =

28.840 ac, 79.23% Impervious, Inflow Depth > 9.98" for 50 yrs. 24 hrs. event 360.28 cfs @ 12.02 hrs, Volume= 23.975 af 21.28 cfs @ 13.02 hrs, Volume= 17.463 af, Atten= 94%, Lag= 59.7 min 21.28 cfs @ 13.02 hrs, Volume= 17.463 af

Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 11.42' @ 13.02 hrs Surf.Area= 2.587 ac Storage= 15.089 af Plug-Flow detention time= 350.5 min calculated for 17.427 af (73% of inflow) Center-of-Mass det. time= 259.3 min ( 1,010.5 - 751.2 ) Volume #1A #2A

Invert 5.00'

Avail.Storage 15.157 af

4.50'

1.117 af 16.274 af

Storage Description CONSPAN 14x 7 x 900 Inside #2 Inside= 168.0"W x 84.0"H => 91.70 sf x 8.00'L = 733.6 cf Outside= 184.0"W x 92.0"H => 110.98 sf x 8.00'L = 887.8 cf 469.57'W x 240.00'L x 8.17'H Field A 21.137 af Overall - 18.344 af Embedded = 2.793 af x 40.0% Voids Total Available Storage

Storage Group A created with Chamber Wizard Device #1

Routing Primary

Invert 5.00'

Outlet Devices 18.0" Round Culvert L= 100.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 5.00' / 5.00' S= 0.0000 '/' Cc= 0.900 n= 0.010 PVC, smooth interior

Primary OutFlow Max=21.28 cfs @ 13.02 hrs HW=11.42' (Free Discharge) 1=Culvert (Barrel Controls 21.28 cfs @ 12.04 fps)


Type II 24-hr 50 yrs. 24 hrs. Rainfall=10.60"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 28

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Pond 3P: STORAGE A Hydrograph 400 380

Inflow Primary

360.28 cfs

360

Inflow Area=28.840 ac Peak Elev=11.42' Storage=15.089 af 18.0" Round Culvert n=0.010 L=100.0' S=0.0000 '/'

340 320 300 280

Flow (cfs)

260 240 220 200 180 160 140 120 100 80 60 40

21.28 cfs

20 0 0

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Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 29

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment A: Area "A" Runoff

=

405.14 cfs @ 12.02 hrs, Volume=

27.088 af, Depth>11.27"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90" CN 85 98 95

Description Hy, Saline, Herbaceous good condition Hy, Saline, paved areas Weighted Average 20.77% Pervious Area 79.23% Impervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 2.4 300 0.0200 2.07 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.69" 9.0 815 0.0055 1.51 Shallow Concentrated Flow, Paved Kv= 20.3 fps 11.4 1,115 Total

Subcatchment A: Area "A" Hydrograph

Flow (cfs)

* *

Area (ac) 5.990 22.850 28.840 5.990 22.850

440 420 400 380 360 340 320 300 280 260 240 220 200 180 160 140 120 100 80 60 40 20 0

Runoff

405.14 cfs

Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90" Runoff Area=28.840 ac Runoff Volume=27.088 af Runoff Depth>11.27" Flow Length=1,115' Tc=11.4 min CN=95

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Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 30

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Subcatchment B: Area "B" Runoff

=

480.70 cfs @ 12.11 hrs, Volume=

40.589 af, Depth>11.38"

Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90" CN 85 98 96

Description Hy, Saline, Herbaceous good condition Hy, Saline, Paved Weighted Average 16.35% Pervious Area 83.65% Impervious Area

Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 3.9 300 0.0060 1.28 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.69" 15.7 1,513 0.0063 1.61 Shallow Concentrated Flow, Paved Kv= 20.3 fps 19.6 1,813 Total

Subcatchment B: Area "B" Hydrograph

Flow (cfs)

* *

Area (ac) 7.000 35.810 42.810 7.000 35.810

520 500 480 460 440 420 400 380 360 340 320 300 280 260 240 220 200 180 160 140 120 100 80 60 40 20 0

Runoff

480.70 cfs

Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90" Runoff Area=42.810 ac Runoff Volume=40.589 af Runoff Depth>11.38" Flow Length=1,813' Tc=19.6 min CN=96

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Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 31

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Summary for Pond 2P: (new Pond) Inflow Area = Inflow = Primary =

42.810 ac, 83.65% Impervious, Inflow Depth > 11.38" for 100 yrs. 24 hrs. event 480.70 cfs @ 12.11 hrs, Volume= 40.589 af 480.70 cfs @ 12.11 hrs, Volume= 40.589 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs

Pond 2P: (new Pond)

Flow (cfs)

Hydrograph 520 500 480 460 440 420 400 380 360 340 320 300 280 260 240 220 200 180 160 140 120 100 80 60 40 20 0

Inflow Primary

480.70 cfs

Inflow Area=42.810 ac

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Proposed Conditions Mercado Central

Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90"

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Printed 7/19/2012 Page 32

Summary for Pond 3P: STORAGE A Inflow Area = Inflow = Outflow = Primary =

28.840 ac, 79.23% Impervious, Inflow Depth > 11.27" for 100 yrs. 24 hrs. event 405.14 cfs @ 12.02 hrs, Volume= 27.088 af 80.81 cfs @ 12.40 hrs, Volume= 19.879 af, Atten= 80%, Lag= 22.7 min 80.81 cfs @ 12.40 hrs, Volume= 19.879 af

Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 77.33' @ 12.40 hrs Surf.Area= 2.587 ac Storage= 16.274 af Plug-Flow detention time= 339.1 min calculated for 19.879 af (73% of inflow) Center-of-Mass det. time= 247.7 min ( 996.8 - 749.1 ) Volume #1A #2A

Invert 5.00'

Avail.Storage 15.157 af

4.50'

1.117 af 16.274 af

Storage Description CONSPAN 14x 7 x 900 Inside #2 Inside= 168.0"W x 84.0"H => 91.70 sf x 8.00'L = 733.6 cf Outside= 184.0"W x 92.0"H => 110.98 sf x 8.00'L = 887.8 cf 469.57'W x 240.00'L x 8.17'H Field A 21.137 af Overall - 18.344 af Embedded = 2.793 af x 40.0% Voids Total Available Storage

Storage Group A created with Chamber Wizard Device #1

Routing Primary

Invert 5.00'

Outlet Devices 18.0" Round Culvert L= 100.0' RCP, rounded edge headwall, Ke= 0.100 Inlet / Outlet Invert= 5.00' / 5.00' S= 0.0000 '/' Cc= 0.900 n= 0.010 PVC, smooth interior

Primary OutFlow Max=80.25 cfs @ 12.40 hrs HW=76.39' (Free Discharge) 1=Culvert (Barrel Controls 80.25 cfs @ 45.41 fps)


Type II 24-hr 100 yrs. 24 hrs. Rainfall=11.90"

Proposed Conditions Mercado Central

Printed 7/19/2012 Page 33

Prepared by HP HydroCAD® 9.10 s/n 06647 © 2010 HydroCAD Software Solutions LLC

Pond 3P: STORAGE A

Flow (cfs)

Hydrograph 440 420 400 380 360 340 320 300 280 260 240 220 200 180 160 140 120 100 80 60 40 20 0

Inflow Primary

405.14 cfs

Inflow Area=28.840 ac Peak Elev=77.33' Storage=16.274 af 18.0" Round Culvert n=0.010 L=100.0' 80.81 cfs S=0.0000 '/' 0

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Apendice D - H H REPORT 07 19 2012.pdf  

Estudio de prefactibilidad para la creación de un nuevo mercado en San Juan

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