Stormwater Report Addendum #1 (City & SWFWMD Submittal)

Transcription

1 Stormwater Report Addendum #1 (City & SWFWMD Submittal) Lakeland Circle K Lakeland, Florida Prepared for: Gryboski, Howe, Gravely 101 S. Bay Blvd., Suite B-3 Anna Maria, FL Prepared by: FBPR Certificate of Authorization No.: Anthony L. Celani, P.E. Florida Registration #76056 September 15, 2016 Anthony L. Celani Digitally signed by Anthony L. Celani DN: cn=anthony L. Celani, o=professional Engineer, ou=#76056, =tony@campoengine ering.com, c=us Date: :45:13-04'00' THIS ITEM HAS BEEN ELECTRONICALLY SIGNED AND SEALED BY MATTHEW D. CAMPO, PE ON USING A DIGITAL SIGNATURE. PRINTED COPIES OF THIS DOCUMENT ARE NOT CONSIDERED SIGNED AND SEALED AND THE SIGNATURE MUST BE VERIFIED ON ANY ELECTRONIC COPIES.

2 Table of Contents I. Introduction II. III. IV. General Information A. Location B. Sewer Service and Water Supply C. Zoning, Land Use and Other Permits D. Maintenance of the Stormwater System Basis of Analysis A. Rainfall Intensity Amounts B. Soils C. Runoff Curve Number D. Time of Concentration E. Groundwater Conditions F. Hydrograph Development G. Design Criteria Description of Analysis A. Existing Conditions B. Proposed Conditions C. 100-Year Floodplain D. Water Quality Treatment E. Wetland Conditions V. Appendices A. CN and TC Calculations B. Water Quality & Stage Storage Calculations C. MODRET Analysis (Treatment Volume Drawdown) D. AdICPR Drainage Analysis (Pre and Post Conditions) E. Drainage Basin Maps F. Geotechnical Report

3 I. Introduction It is the intent of this report to produce a quality surface water management plan for the development of a Circle K gas station and convenience store along with a future development parcel, which satisfies the requirements established by the Florida Department of Transportation (FDOT). The proposed project consists of constructing a new 4,920 square foot Circle K convenience store with 6,000 sf canopy and gas pumps; a acre future development parcel; the associated site infrastructure; and two (2) dry stormwater ponds to provide treatment and attenuation. II. General Information A. Location The Circle K Lakeland project is a 4.33 acre site located at the northwest corner of N. Florida Ave. and West Tenth Street, physical address at 1500 N. New York Ave, Lakeland, Florida; Section 23, Township 28S, Range 12E. B. Sewer Service and Water Supply The city of Lakeland Utility Department shall provide sewage collection and potable water. C. Zoning, Land Use and Other Permits 1. Zoning Existing zoning for the site is MF-2 which is compatible with the proposed development. 2. Land Use Existing land use is Commercial, Mixed Use, which is compatible with the proposed development. 3. Other Permits Currently permits are being processed through the FDOT, Southwest Florida Water Management District, and City of Lakeland. D. Maintenance of the Stormwater System The proposed site will contain two (2) dry surface ponds that will be owned, operated and maintained by the Owner. A regular maintenance program will be implemented for the site in a form similar to the "Operating and Maintenance Instructions" listed below and per notes on the Construction Plans. 1. OPERATION AND MAINTENANCE INSTRUCTIONS

4 Operation The project's stormwater management system is a gravity operated system and requires no operator action other than maintenance. Maintenance 1. Swales: All swales shall be periodically mowed and cleaned. During the mowing operation, swales shall be inspected for bare spots, damage, and erosion. Any bare spots greater than one (1) square foot in area shall be seeded or sodded to replace the grass cover. In case of erosion or damage where underlying soil is missing, the missing soil shall be replaced and the area brought back to grade then seeded or sodded as required. 2. Inlet Grates: Inlet grates will be checked monthly for damage or blockage. Any damaged grates will be replaced or repaired. Any debris blocking full flow through the gate will be removed. 3. Pipes and Inlets: Pipes and inlets will be inspected yearly for damage or blockage. Any damaged pipes or inlets will be repaired or replaced. Any trash, debris, or sand deposits will be removed. 4. Retention Areas: All ponds shall be periodically mowed and cleaned. During the mowing operation, ponds shall be inspected for bare spots, damage, and erosion. Any bare spots greater than one (1) square foot in area shall be seeded or sodded to replace the grass cover. In case of erosion or damage where underlying soil is missing, the missing soil shall be replaced and the area brought back to grade then seeded or sodded as required. III. Basis of Analysis The data input to the hydrologic model was developed using methodologies outlined in the U. S. Department of Agriculture Soil Conservation Service's (SCS) Urban Hydrology for Small Watersheds Technical Release 55 (TR-55) manual. Other references used include the Southwest Florida Water Management District's (SWFWMD) Environmental Resource Permitting Information Manual and the FDOT Drainage Manual. The topography survey for the project area was developed by EBI Surveying. Soils data and land use conditions information were obtained from the SCS's Soil Survey for Polk County and on-site observations. In addition, a detail geotechnical investigation with percolation tests and seasonal high water determinations were completed by ATC Group Services, LLC. A. Rainfall Intensity Amounts The 25 year storm events over duration of 24 hours were used to develop the hydrograph for the storm analysis. Rainfall intensities for the 25yr/24hr and storm events were determined from SWFWMD rainfall distributions. Per City of Lakeland

5 Stormwater criteria, the pre/post development discharge rate for the system is limited to the 25 year/24 hour storm event. In addition, the 10 year/24 hour storm event and 100 year/24 hour storm events were evaluated for peak flooding conditions and low pavement elevations. Event (year) Table III-A Rainfall Depths Amount (inches) 25-year/24-hour year/24-hour year/24-hour 6.5 It should be noted that this site currently discharges into the FDOT ROW and a separate FDOT critical duration analysis was completed for an FDOT drainage connection permit. B. Soils The SCS Soils Manual maps the site within Tavares Soils which is a hydrologic group type A soil group. In addition, a detailed geotechnical study has been prepared by ATC Group Services, LLC and is located in the Appendix of this report. The geotechnical investigation provides current and actual field conditions for the proposed design. C. Runoff Curve Number Curve numbers have been selected from the Curve Number table within TR-55 as noted below. Table III-C Pre/Post Development Land Use Land Use CN Existing/Proposed Impervious 98 Open Space Fair Condition (HSG A ) 49 Open Space Good Condition (HSG A ) 39 Stormwater Pond 98

6 D. Time of Concentration In the existing condition Basin 10 time of concentration was calculated and found to be 21.7 minutes. For post development conditions, 10 minutes was used as a minimum time of concentration (tc) per the FDOT Drainage Manual. Time of Concentration calculated for the bypass system was 12.0 minutes. Please refer to the Appendix for time of concentration calculations. E. Groundwater Conditions Based on the geotechnical study, a seasonal high groundwater was estimated for the stormwater pond area. At Pond 10 the area appears to have an average existing ground elevation of feet. The seasonal high depth in this location from the report is 4.0 feet. As a result, the seasonal high water level at Pond 10 used in the design was elevation feet. At Pond 30 the area appears to have an average existing ground elevation of feet. The seasonal high depth in this location from the report is 4.0 feet. As a result, the seasonal high water level at Pond 10 used in the design was elevation feet. F. Hydrograph Development That hydrologic analysis of the site was performed using the SCS Runoff Method and the Unit Hydrographs as noted in the FDOT Drainage Manual. The Advanced ICPR computer program was used to apply the unit hydrograph method to generate runoff hydrographs from which peak flow rates were then extracted. A dimensionless unit hydrograph with a peak factor of 256 was used for the analysis. The above unit hydrograph was distributed over time using the FDOT Critical Duration Distributions. The SCS unit hydrograph procedure requires input data describing physical features of each sub-basin in the system including drainage areas, curve numbers, and times of concentration. These parameters are dependent on land use, soils, and topography and are all interrelated. G. Design Criteria The stormwater management system has been designed for the treatment and attenuation volume as required by the City of Lakeland, SWFMD and the FDOT. For the City and SWFWMD, the stormwater system was designed to attenuate the 25- year, 24-hour rainfall event pre vs. post for the proposed development. IV. Description of Analysis A. Existing Conditions

7 The existing conditions represent a vacant undeveloped lot with remnants of a historical stormwater system. The site used to contain housing which was demolished in the early 2000 s. The site currently drains from the southwest corner to the northeast corner and ultimately out into the FDOT ROW. For purposes of establishing allowable discharge rates, the site was viewed as undeveloped with sheet flow out into the ROW. B. Proposed Conditions Table IV-A Pre Development Conditions Watershed Table Area Tc Basin ID CN (acres) (min) Basin The site will continue to maintain historical drainage patterns and outfall into the existing FDOT curb inlet located in the N. Florida Ave. right of way. Note that treatment and attenuation is provided for in the dry stormwater ponds. The post development conditions are noted below in Table IV-B. Table IV-B Post Development Conditions Watershed Table Basin ID Area (acres) CN Tc (min) Basin Basin 20(*) Basin 30(*) Basin Bypass Total (*)Note: Basin 20 & Basin 30 are located within areas of future development. Stormwater system designed for max allowable 80% impervious coverage in these areas. Table IV-C presents selected design criteria for the stormwater systems and discharge structure. Table IV-C Pond Design Conditions

8 System ID 25-Year 24 Hour DHW 100-Year 24 Hour DHW TOB EL (ft NAVD) Discharge Structure (ft-navd) (ft-navd) Pond Junction Box Internal Weir Pond Modified type C Inlet Note that The Finish Floor Elevation is elevation ft, which is at least 1.0 foot above the 100 year stage Elevation. The pond top of bank is over 6 above the 25 year design high elevation. C. 100 Year Floodplain The site lies within Flood Zone X, which is described as areas determined to be outside of the 100 year flood plain per F.I.R.M. Map No C0304F, dated 12/20/2000. D. Water Quality Treatment Water quality treatment will be provided to meet criteria set forth by SWFWMD. Silt, oil, and floatable materials will be removed from the runoff via a baffle/skimmer device. The 1/2 inch of runoff from the contributing drainage basin will be treated within the existing surface water management system via dry retention. A draw down analysis using Modret and draw down analysis approach has been provided in the Appendix to demonstrate compliance and recovery of the treatment volume within 72 hours or less. In addition, the site location has been reviewed to determine if it is within a known impaired is located within a drainage basin that contributes runoff to an impaired water body per the FDPE 303(d) list. The site is within WBID 1497, which was impaired for Fecal Coliform, Dissolved Oxygen, and Nutrients (Chlorophyll-a). According to Robert Wiwi of the FDEP, their preliminary assessments for Group 3 Cycle 3 show that Dissolved Oxygen will be delisted into category 4c (Natural Conditions) and Nutrients (Chlorophyll-a) will be delisted to 2, however, Fecal Coliform will remain impaired (see attached for details). Stormwater runoff does not contribute to additional fecal coliform concentration levels and from the Southwest Florida Water Management District s intent, additional nutrient runoff of nitrogen and phosphorous dictate the necessity of additional stormwater treatment. Furthermore, fecal coliform pollutants general come from septic tank and septic drain field leaching into the groundwater. This project will connect into the City of Lakeland Sewer System and will not contribute to any additional fecal coliform discharge. E. Wetland Conditions

9 No wetlands or other unique hydrologic indicators are within the project area and as a result there are no wetland impacts.

10 V. Appendices A. CN and TC Calculations B. Water Quality Calculations & Stage/Storage C. MODRET Analysis (Treatment Volume Drawdown) D. AdICPR Drainage Analysis (Pre and Post Conditions) E. Drainage Basin Maps (Pre and Post) F. Geotechnical Report

11 A. CN and TC Calculations

12 CAMPO ENGINEERING, INC Project Name : Project Number : Date : Designed by : Lakeland Circle K /14/16 ALC CN Calculations Pre-Development Basin PRE-10 Description Area (A) CN CN x A Greenspace Area ac Impervious Area ac Gravel Driveway ac Pond ac Total Area ac Cover type & hydrologic cond. Open Grass, Fair Cond., Type A Asphalt/Vehicular Use Gravel Storm Water = Weighted CN Post-Development Basin POST-10 (Circle K) Description Area (A) CN C x A Greenspace Area ac Impervious Area ac Pond ac Total Area ac Cover type & hydrologic cond. Open Grass, Good Cond., Type A Asphalt/Vehicular Use/Building/Sidewalk Storm Water = Weighted CN Post-Development POST-20 (Future Dev) Description Area (A) CN C x A Greenspace Area ac Pond ac Impervious Area ac Total Area ac Cover type & hydrologic cond. Open Grass, Good Cond., Type A Storm Water Asphalt/Vehicular Use/Building/Sidewalk = Weighted CN Note: Max Allowable 80% of Future Impervious Post-Development POST-30 (Pond 30) Description Area (A) CN C x A Greenspace Area ac Pond ac Impervious Area ac Total Area ac Cover type & hydrologic cond. Open Grass, Good Cond., Type A Storm Water Asphalt/Vehicular Use/Building/Sidewalk = Weighted CN Note: Max Allowable 80% of Future Impervious Post-Development POST-Bypass Description Area (A) CN C x A Greenspace Area ac Pond ac Impervious Area ac Total Area ac Cover type & hydrologic cond. Open Grass, Good Cond., Type A Storm Water Asphalt/Vehicular Use/Building/Sidewalk = Weighted CN

13 81 57' 31'' W Soil Map Polk County, Florida 81 57' 26'' W 28 3' 51'' N ' 51'' N ' 44'' N ' 44'' N 81 57' 31'' W N Map Scale: 1:659 if printed on B portrait (11" x 17") sheet. Meters Feet Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 17N WGS ' 26'' W Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 4/1/2016 Page 1 of 3

14 Soil Map Polk County, Florida MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:20,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Polk County, Florida Survey Area Data: Version 12, Nov 19, 2015 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Nov 28, 2014 Dec 9, 2014 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 4/1/2016 Page 2 of 3

15 Soil Map Polk County, Florida Map Unit Legend Polk County, Florida (FL105) Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 63 Tavares-Urban land complex % Totals for Area of Interest % Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 4/1/2016 Page 3 of 3

16 Map Unit Description: Tavares-Urban land complex---polk County, Florida Polk County, Florida 63 Tavares-Urban land complex Map Unit Setting National map unit symbol: 1jtwc Elevation: 20 to 120 feet Mean annual precipitation: 46 to 54 inches Mean annual air temperature: 70 to 77 degrees F Frost-free period: 350 to 365 days Farmland classification: Not prime farmland Map Unit Composition Tavares and similar soils: 75 percent Urban land: 25 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Tavares Setting Landform: Flats on marine terraces, rises on marine terraces Landform position (three-dimensional): Talf Down-slope shape: Convex Across-slope shape: Linear Parent material: Eolian or sandy marine deposits Typical profile A - 0 to 8 inches: fine sand C - 8 to 80 inches: fine sand Properties and qualities Slope: 0 to 2 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Moderately well drained Runoff class: Negligible Capacity of the most limiting layer to transmit water (Ksat): High to very high (5.95 to in/hr) Depth to water table: About 42 to 72 inches Frequency of flooding: None Frequency of ponding: None Salinity, maximum in profile: Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm) Sodium adsorption ratio, maximum in profile: 4.0 Available water storage in profile: Very low (about 2.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3s Hydrologic Soil Group: A Other vegetative classification: Forage suitability group not assigned (G154XB999FL) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 4/1/2016 Page 1 of 2

17 Map Unit Description: Tavares-Urban land complex---polk County, Florida Description of Urban Land Setting Landform: Marine terraces Landform position (three-dimensional): Interfluve, talf Down-slope shape: Linear Across-slope shape: Linear Parent material: No parent material Interpretive groups Land capability classification (irrigated): None specified Other vegetative classification: Forage suitability group not assigned (G154XB999FL) Data Source Information Soil Survey Area: Polk County, Florida Survey Area Data: Version 12, Nov 19, 2015 Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 4/1/2016 Page 2 of 2

18 9/14/2016 Time of Concentration Flow Type Length (feet) Slope Velocity Land Use P (inches) n Flow Time BASIN From To (Ft /Sec) (hours) PRE Sheet n/a Green Space Shallow Grass/Woods Concentrated n/a Pipe Flow Pipe 4.50 n/a Time of Concentration 0.36 << Use 21.7 minutes Use 10 Minutes Minimum For Post Flow Type Length (feet) Slope Velocity Land Use P (inches) n Flow Time BASIN From To (Ft /Sec) (hours) POST Sheet n/a Green Space BYPASS Open Channel Grass/Woods Pipe Flow Pipe 4.50 n/a Time of Concentration 0.20 << Use 12 minutes 9/14/2016 Page 1

19 B. Water Quality Calculations & Stage/Storage

20 CAMPO ENGINEERING, INC Project Name : Project Number : Date : Designed by : Lakeland Circle K /14/16 ALC Calculate the Required Treatment Volume Basin Area ac Treatment Volume = (Total Basin Area (ac) *(0.5 in) * ( 1 ft / 12 in )) ac-ft Provided Retention Volume = Elevation (feet) Pond Area (acres) (cu- Volume ft) (sq- Pond Area ft) Volume (ac-ft) Cum. Volume (ac-ft) Cum. Volume (cu-ft) Top of Bank Weir SHW

21 CAMPO ENGINEERING, INC Project Name : Project Number : Date : Designed by : Lakeland Circle K /14/16 ALC Calculate the Required Treatment Volume Basin Area ac Treatment Volume = (Total Basin Area (ac) *(0.5 in) * ( 1 ft / 12 in )) ac-ft Provided Retention Volume = Elevation (feet) (sq- Pond Area ft) Pond Area (acres) Volume (cu-ft) Volume (ac-ft) Cum. Volume (ac-ft) Cum. Volume (cu-ft) Top of Bank Weir SHW

22 Tony Celani From: Sent: To: Cc: Subject: Attachments: Wiwi, Robert Friday, April 01, :16 PM Mostyn, Jessica; ODonnell, Kevin RE: NWC 10th St & N Florida Ave Lakeland FL - Impaired Water Body 1497 Saddle Creek Status.pdf Good afternoon Mr. Celani, WBID 1497, where this site is located, is currently (as of our Group 3 Cycle 2 assessments) impaired for Fecal Coliform, Dissolved Oxygen, and Nutrients (Chlorophyll a). Our preliminary assessments for Group 3 Cycle 3 show that Dissolved Oxygen will be delisted into category 4c (Natural Conditions) and Nutrients (Chlorophyll a) will be delisted to 2, however, Fecal Coliform will remain impaired. Please keep in mind that these preliminary assessments have not been adopted by secretarial order and are subject to change. The attached map shows the site s location in relation to WBID Please let me know if you have any questions or need any additional information. Thank you, Robert Wiwi Environmental Specialist II Division of Environmental Assessment & Restoration Water Quality Assessment Program Watershed Assessment Section 2600 Blair Stone Rd MS 3560 Tallahassee, FL robert.wiwi@dep.state.fl.us From: Mostyn, Jessica Sent: Friday, April 01, :02 PM To: Wiwi, Robert <Robert.Wiwi@dep.state.fl.us> Cc: ODonnell, Kevin <Kevin.ODonnell@dep.state.fl.us> Subject: FW: NWC 10th St & N Florida Ave Lakeland FL Impaired Water Body Robert, Can you look into the impairment status for this WBID? Thank you, Jess From: Tony Celani [mailto:tony@campoengineering.com] Sent: Friday, April 01, :40 AM To: Mostyn, Jessica; ODonnell, Kevin Subject: NWC 10th St & N Florida Ave Lakeland FL Impaired Water Body 1

23 We are trying to determine if our site is located within the basin of an impaired water body. The site is located at Northwest corner of 10 th St and N Florida Ave in Lakeland FL, see attached location map for details. The WBID appears to be 1497 Please let me know if you have any questions. Thank you, 2

24 3

25 5

26 Right-click here to download pictures. To help protect your priv acy, Outlo ok prevented auto matic downlo ad o f thi s pi ctu re from the In ternet. Dep Customer Survey Anthony L. Celani, P.E. Campo Engineering, Inc East 5 th Avenue Tampa, FL Phone Fax "The Client's Engineering Solution" 6

27 C. MODRET Analysis (Treatment Volume Drawdown)

28 D. AdICPR Drainage Analysis (Pre and Post Conditions)

29 MODRET SUMMARY OF UNSATURATED & SATURATED INPUT PARAMETERS PROJECT NAME : Circle K Pond 10 MANUAL RUNOFF DATA USED UNSATURATED ANALYSIS EXCLUDED Pond Bottom Area 11, ft² Pond Volume between Bottom & DHWL 5, ft³ Pond Length to Width Ratio (L/W) 4.00 Elevation of Effective Aquifer Base ft Elevation of Seasonal High Groundwater Table ft Elevation of Starting Water Level ft Elevation of Pond Bottom ft Design High Water Level Elevation ft Avg. Effective Storage Coefficient of Soil for Unsaturated Analysis 0.30 Unsaturated Vertical Hydraulic Conductivity 6.80 ft/d Factor of Safety 2.00 Saturated Horizontal Hydraulic Conductivity ft/d Avg. Effective Storage Coefficient of Soil for Saturated Analysis 0.30 Avg. Effective Storage Coefficient of Pond/Exfiltration Trench 1.00 Hydraulic Control Features: Top Bottom Left Right Groundwater Control Features - Y/N N N N N Distance to Edge of Pond Elevation of Water Level Impervious Barrier - Y/N N N N N Elevation of Barrier Bottom Analysis Date: 6/17/2016

30 MODRET TIME - RUNOFF INPUT DATA PROJECT NAME: CIRCLE K POND 10 STRESS PERIOD NUMBER INCREMENT OF TIME (hrs) VOLUME OF RUNOFF (ft³) Unsat , Analysis Date: 6/17/

31 MODRET SUMMARY OF RESULTS PROJECT NAME : Circle K Pond 10 CUMULATIVE TIME (hrs) WATER ELEVATION (feet) INSTANTANEOUS INFILTRATION RATE (cfs) AVERAGE INFILTRATION RATE (cfs) CUMULATIVE OVERFLOW (ft³) * Analysis Date: 6/17/2016

32 MODRET SUMMARY OF RESULTS PROJECT NAME : Circle K Pond 10 CUMULATIVE TIME (hrs) WATER ELEVATION (feet) INSTANTANEOUS INFILTRATION RATE (cfs) AVERAGE INFILTRATION RATE (cfs) CUMULATIVE OVERFLOW (ft³) Analysis Date: 6/17/2016

33 MODRET SUMMARY OF RESULTS PROJECT NAME : Circle K Pond 10 CUMULATIVE TIME (hrs) WATER ELEVATION (feet) INSTANTANEOUS INFILTRATION RATE (cfs) AVERAGE INFILTRATION RATE (cfs) CUMULATIVE OVERFLOW (ft³) Maximum Water Elevation: hours * Time increment when there is no runoff Maximum Infiltration Rate: ft/day hours Analysis Date: 6/17/2016

34 5,800 5,600 5,400 5,200 5,000 4,800 4,600 4,400 4,200 4,000 3,800 3,600 3,400 3,200 3,000 2,800 2,600 2,400 2,200 2,000 1,800 1,600 1,400 1,200 1, INFILTRATION : CIRCLE K POND Time (hrs) Total Volume Infiltrated = 5,921 ft³ Volume Infiltrated (ft³)

35 INFILTRATION : CIRCLE K POND Time (hrs) Max Water Elevation = ft Water Elevation (ft)

36 MODRET SUMMARY OF UNSATURATED & SATURATED INPUT PARAMETERS PROJECT NAME : Circle K Pond 30 MANUAL RUNOFF DATA USED UNSATURATED ANALYSIS EXCLUDED Pond Bottom Area 2, ft² Pond Volume between Bottom & DHWL 1, ft³ Pond Length to Width Ratio (L/W) 1.67 Elevation of Effective Aquifer Base ft Elevation of Seasonal High Groundwater Table ft Elevation of Starting Water Level ft Elevation of Pond Bottom ft Design High Water Level Elevation ft Avg. Effective Storage Coefficient of Soil for Unsaturated Analysis 0.30 Unsaturated Vertical Hydraulic Conductivity 6.80 ft/d Factor of Safety 2.00 Saturated Horizontal Hydraulic Conductivity ft/d Avg. Effective Storage Coefficient of Soil for Saturated Analysis 0.30 Avg. Effective Storage Coefficient of Pond/Exfiltration Trench 1.00 Hydraulic Control Features: Top Bottom Left Right Groundwater Control Features - Y/N N N N N Distance to Edge of Pond Elevation of Water Level Impervious Barrier - Y/N N N N N Elevation of Barrier Bottom Analysis Date: 9/14/2016

37 MODRET TIME - RUNOFF INPUT DATA PROJECT NAME: CIRCLE K POND 30 STRESS PERIOD NUMBER INCREMENT OF TIME (hrs) VOLUME OF RUNOFF (ft³) Unsat , Analysis Date: 9/14/

38 MODRET SUMMARY OF RESULTS PROJECT NAME : Circle K Pond 30 CUMULATIVE TIME (hrs) WATER ELEVATION (feet) INSTANTANEOUS INFILTRATION RATE (cfs) AVERAGE INFILTRATION RATE (cfs) CUMULATIVE OVERFLOW (ft³) * Analysis Date: 9/14/2016

39 MODRET SUMMARY OF RESULTS PROJECT NAME : Circle K Pond 30 CUMULATIVE TIME (hrs) WATER ELEVATION (feet) INSTANTANEOUS INFILTRATION RATE (cfs) AVERAGE INFILTRATION RATE (cfs) CUMULATIVE OVERFLOW (ft³) Analysis Date: 9/14/2016

40 MODRET SUMMARY OF RESULTS PROJECT NAME : Circle K Pond 30 CUMULATIVE TIME (hrs) WATER ELEVATION (feet) INSTANTANEOUS INFILTRATION RATE (cfs) AVERAGE INFILTRATION RATE (cfs) CUMULATIVE OVERFLOW (ft³) Maximum Water Elevation: hours * Time increment when there is no runoff Maximum Infiltration Rate: ft/day hours Analysis Date: 9/14/2016

41 1,250 1,200 1,150 1,100 1,050 1, INFILTRATION : CIRCLE K POND 30 Time (hrs) Total Volume Infiltrated = 1,250 ft³ Volume Infiltrated (ft³)

42 INFILTRATION : CIRCLE K POND 30 3 Time (hrs) Max Water Elevation = ft Water Elevation (ft)

43 E. Drainage Basin Maps (Pre and Post)

44 I L ENG I NEERS * TRACT "E" (PLAT BOOK 122, PG. 16) C EI CONSTRUCT ION HOUSING AUTHORITY OF LAKELAND PARCEL ID.: NORTH FLORIDA AVENUE (F) IV C * I NSPECTORS PLANNERS * CAMPO ENGINEERING, INC. FBPR CERTIFICATE OF AUTHORIZATION NO.: TRACT "E" (PLAT BOOK 122, PG. 16) HOUSING AUTHORITY OF LAKELAND PARCEL ID.: SUBJECT PARCEL HOUSING AUTHORITY OF LAKELAND PARCEL ID.: EAST 5TH AVENUE TAMPA, FL PHONE: (813) FAX: (813) PROJECT TITLE LAKELAND CIRCLE K - SITE 1410 N. FLORIDA AVE. CITY OF LAKELAND, FLORIDA CLIENT PRE BASIN ACRES GRYBOSKI, HOWE & GRAVELY 101 S. BAY BLVD., SUITE B-3 ANNA MARIA, FL (727) REVISIONS "A" SEE SHEET 2 SEE SHEET 2 SEE SHEET 3 SEE SHEET 3 MATCH LINE MATCH LINE "A" SEE SHEET 2 SEE SHEET 2 SEE SHEET 3 SEE SHEET 3 "A" NO. DESCRIPTION DATE TRACT "E" (PLAT BOOK 122, PG. 16) HOUSING AUTHORITY OF LAKELAND PARCEL ID.: NORTH FLORIDA AVENUE (F) ISSUE DATE: 04/2016 REVIEWED BY: ALC DRAWN BY: ARL DESIGNED BY: ALC PROJECT NUMBER SUBJECT PARCEL HOUSING AUTHORITY OF LAKELAND PARCEL ID.: NAME SEAL NO. SHEET TITLE DATE SHEET NUMBER WEST TENTH STREET (F)

45 I R C E * I I ON I NS PEC T C IV I L E NG CON ST S OR * T UC S ER NE * P LA N N ER S CAMPO ENGINEERING, INC. FBPR CERTIFICATE OF AUTHORIZATION NO.: POST BASIN ACRES MAX IMP AREA 80% 1725 EAST 5TH AVENUE TAMPA, FL PHONE: (813) FAX: (813) POST BASIN BYPASS ACRES PROJECT TITLE LAKELAND CIRCLE K - SITE 1410 N. FLORIDA AVE. POST BASIN ACRES MAX IMP AREA 80% CITY OF LAKELAND, FLORIDA CLIENT GRYBOSKI, HOWE & GRAVELY 101 S. BAY BLVD., SUITE B-3 ANNA MARIA, FL (727) REVISIONS NO. SEE SHEET 2 "A" MATCH LINE "A" MATCH LINE "A" SEE SHEET 2 SEE SHEET 2 SEE SHEET 2 "A" DESCRIPTION DATE "A" "A" SEE SHEET 3 SEE SHEET 3 SEE SHEET 3 SEE SHEET 3 ISSUE DATE: 04/2016 REVIEWED BY: ALC DRAWN BY: ARL DESIGNED BY: ALC POST BASIN ACRES SECTION 3 SECTION 2 SECTION 1 PROJECT NUMBER N SA NAME SEAL NO. SHEET TITLE SHEET NUMBER DATE ONLY

46 F. Geotechnical Report SEE ORIGINAL REPORT DATED JUNE 17, 2016 FOR GEOTECHNICAL REPORT