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HomeMy WebLinkAboutOld Meridian Area Stormwater Phase I Report ~ ~ D C ~ ~ a ,0 D ~ U ~ ~ ~ o o ~ u I ~ , April 24, 2002 Phase I Report Old Meridian Area Stormwater Master Plan Investigations :'7a:~rlt "'lIr.Jit~I. >'iTttlrTf-.. v; Tt~ lJ" o iliff fr )... ,,-~. , C of ~~~,L: I.~.IL _____cw, '" ,.:/ ~~ ~":", Prepared for Carmel, Indiana ~R9N9I-fH{" u U D D D D D D D D D D D D D D D D o Phase I Stormwater Master Plan Old Meridian Area Donohue & Associates, Inc. 101 West Ohio Suite, 820 Indianapolis, Indiana 46204 Phone: 317-267-8200 Phase I Report for Old Meridian Area Stormwater Master Plan Investigations Prepared for Carmel, Indiana April 24, 2002 /~;;J;ZC2;;~:::;,,, //r.(~,~i/ ~""".1-" '\.. 1Jut/' If.\. ;'-;v.:'!-:\ /. :'\l J'..,h ~;'1":~ \ ! ('J ';' \ 1,f.:1 APH j' \ \ I~ R -I ';:., Ecr~:\/:' I) f" I \\'>' CH ,,; "J J \~'.';~ ~ .~ :":'. /,~({\ / \.., ",! <:~~?',,\. (. f?:,\:~/ '.... ;. r'7 ~-:-. n ., ~~~ .J / ,.~~~.-/ Carmel Indiana u o u U D D D D D D o o D o o o o D D Phase I Stormwater Master Plan Old Meridian Area TABLE OF CONTENTS Purpose........................................................................................................................ ................ 1 Project History............................................... '"............................................................................. 1 Location....................................................................................................................... ................ 1 Background....................................................................................................................... .......... 1 Phase I Scope of Work.. ......... .......................... .......... ........... ........................ ............. .................3 Data Gathering........................................................................................................................ 3 Analysis and Sizing Results ....................... ............... ..... .................... ....... ................ .............. 3 Costing....................................................................................................................... ............. 3 Recommendations................................................................................................................... 3 Summary Report ..................................................................................................................... 3 Data Gathering............................................................................................................................ 3 Analysis and Sizing Results........................................................................................................ 5 Little Cool Creek Basin ........... ................... ............... ..... ... ........ .... ............. .............................5 Providence Basin..................................................................................................................... 5 Fertig Basin......................................................................................................................... .... 8 Main Street Basin.................................................................................................................... 8 Collins Basin ........... ..... ..... ............. ............................ ..... ............... ........ ............ ......... .... ........ 8 School Basin............................................................................................................................ 8 School Basin Storage Sites................................................. ............ ...... ......... ...... ........................9 Cost Estimates........................................................................................................................... 11 Recommendations..................................................................................................................... 13 Facilities Recommended....................................................................................................... 13 Future Recommended Activities........................................................................................... 13 Interim Recommendation.......................................................................................................... 13 Storm Water Culvert Improvement Crossing Old Meridian Street.......................................13 APPENDICES Appendix A - School Basin Runoff and Storage Calculations Appendix B - School Basin Site C Runoff and Storage Calculations Appendix C - Interim Recommendation Calculations Appendix D - Conceptual Cost Estimates Page i Carmel, Indiana u o D D D o U D D o o D o o o D o D D Phase I Stormwater Master Plan Old Meridian Area PuRPOSE This report was prepared to identify the feasibility of providing centralized storm water storage and discharge controls to currently undeveloped or soon to be redeveloped parcels in the Old Meridian Area. The goal of the study was to determine if areas within the Old Meridian Area could be served by centralized stormwater storage and if so where would that storage be located and what would the approximate sizes and costs of those facilities be. Investigations into alternative configurations of storage, establishing conceptual design parameters for such storage, and establishing the estimated end user costs are left to the Phase II work. PROJECT HISTORY The Phase I report was initiated during the summer of 2000 and a first draft was completed in November 2000. The Phase I report was finalized in the spring of 2002 after discussions with various property owners could be completed and guidance provided for the report recommendations. LOCA TlON The Old Meridian Area is generally contained within the following boundaries and is shown on Figure 1 on the following page: ~ On the west and north by Route 31 ~ On the east by Guilford Road ~ On the south by the Arbors Apartments, 126th Street alignment, and areas fronting on Old Meridian and Pennsylvania Street extending south to the intersection of Rt. 31 and Old Meridian. BACKGROUND The Old Meridian Corridor area has been identified as an area where significant redevelopment activities may take place in the near future as well as rapid development of currently vacant land. The City has directed the preparation of a master plan for development activities in this area, and is currently in the initial stages of implementation. As part of this Master Planning process, the City has identified that it would be advantageous to prepare a storm water storage and discharge control plan. The intent of the storm water plan would be to allow individual parcels to develop without the need to include storm water detention or retention facilities on individual parcels. The City gains greater control of storm water discharges from the area, and the property owners benefit by having more developable land and thereby higher property values. The Storm Water Master Plan is broken into 2 phases of work. The first phase, which this report summarizes, evaluates the feasibility of providing centralized storm water storage, strictly from an engineering perspective. Questions such as the upstream basin size, potential location of storage facilities, storage basin size, approximate cost of storage facilities, and other engineering criteria are investigated and summarized. The second phase of work builds on the feasibility findings by providing detailed evaluations of alternative storage configurations and refinement of the cost considerations for those areas where centralized storage was determined to be feasible. Page I of 14 Carmel, Indiana ....., ~ ~ ~ -.....l ~ ..... ~ ~ ~ ....... ~ -- ~ ~ ~ -....... ~ ~ .R9N9l1H~@ '^",,,-, SCALE : 1 "= 500' FIGURE #1 STUDY AREA CITY OF CARMEL CARMEL STORMWATER EVALUATION u U D D D D D D D D D D D o D D D D o Phase I Stormwater Master Plan Old Meridian Area PHASE I SCOPE OF WORK The scope of work for this phase of the project consisted of data gathering, analysis of the data, rough conceptual system layout, sizing calculations, cost estimation of the potential storage facilities, and preparation of this summary. The following paragraphs detail the work included in each of the above work tasks. DATA GATHERING In the data gathering work task we obtained and reviewed the available engineering documents relating to storm water collection, conveyance and storage within or adjacent to the study area. The data gathering efforts also included identifying existing drainage paths, rainfall data, and a field investigation of the study area to further enhance knowledge of the existing drainage facilities. ANALYSIS AND SIZING RESULTS In the analysis work tasks, we reviewed the data obtained and formed general conclusions about the existing drainage facilities in place. We also determined if it was feasible and/or realistic to construct alterations to the existing systems and centralized storage facilities. If so we then determined the locations of potential storage sites, identified the approximate times of concentration, the approximate area of each basin, and calculated the conceptual storage volumes required for redeveloped conditions. COSTING In the costing work task, centralized storm water storage facilities construction costs were estimated. The estimates included the construction costs for the storage projects along with the design, financial, and legal costs. We did not attempt to identify how the costs for the facilities would be appropriated to the various individual parcels within a drainage basin as that work will be part of Phase II. RECOMMENDATIONS The recommendations phase of the work identified those facilities and future work which is needed to develop the project through construction. SUMMARY REpORT The final task in the initial phase of work included the preparation of this summary which documents the major findings and conclusions of the work performed. DATA GATHERING Documents were obtained from the City Engineering and planning departments, Indiana Department Of Transportation, Hamilton County Surveyors office, and the Carmel-Clay School District. Documents were reviewed pertaining to the following developments within or bordering the study area: . St. Vincent's Hospital and ancillary buildings . Pro Med Limited (NE of Guilford and Old Meridian) . St. Vincent's Medical Pavilion Office Complex (South of Guilford and Old Meridian intersection) . Silver Corporation (NW comer of Main and Guilford) Page 3 of 14 Carmel, Indiana D D U D U D U D D D D D o D U o o o u Phase I Stormwater Master Plan Old Meridian Area . Carmel Junior High School . College Wood Elementary School . The Arbors Apartments . Carmel Science and Technology Center . Duke Property (SE comer of 126th and Rt 31) . Meijer Department Store . Summer Trace Retirement community . Providence Development . Route 31 construction plans The City Engineering department also provided electronic copies of available mapping of the study area which included topographic information and property boundaries. Even after review of the above documents, not all currently developed parcels of land were able to be documented sufficiently to enable an accurate evaluation of the storm water conveyance and control features. Generally the areas where information was not located or available were the North Meridian Heights neighborhood and residential lots developed under the county guidance. In those ca~es field investigations were conducted to establish actual drainage patterns and provide a general overview and confirmation of the storm water facilities currently in place. Rainfall data was developed based on intensity/duration/frequency curves for the Indianapolis vicinity prepared by HERPICC Storm Water Drainage Manual. Table 1 below presents the rainfall data used in the evaluations. Table 1 Rainfall Intensities -IDF Equation for Indianapolis Area 10 0.89 5.22 1.44 7.78 20 1.23 4.02 1.99 5.99 30 1.57 3.25 2.53 4.84 60 2.00 2.03 3.21 3.03 120 2.46 1.11 3.97 1.87 180 2.72 0.84 4.38 1.42 240 2.88 0.68 4.63 1.15 360 3.19 0.50 5.13 0.85 480 3.36 0.40 5.40 0.67 720 3.70 0.29 5.95 0.48 1080 3.99 0.20 6.43 0.34 1440 4.25 0.16 6.84 0.27 Page 4 of 14 Carmel, Indiana U D D D D D D D o o u o o D D D o U U Phase I Stormwater Master Plan Old Meridian Area ANALYSIS AND SIZING RESULTS Review of the documents obtained and information gathered in the field allowed for the delineation of storm water drainage basins, along with a not to scale conveyance and control atlas map, which documented the significant storm water features. Six existing drainage basins were identified during this process. The six basins identified were: ~ Fertig (Areas draining directly into the Fertig legal drain) ~ Providence (Areas draining through the Providence Apartments development) ~ School (Areas draining through the elementary and Jr. High property) ~ Main Street (drainage basin generally centered on Main Street) ~ Collins (Areas draining directly into the Collins legal drain) ~ Little Cool Creek (Areas draining directly into the Little Cool Creek) The Six basins and major existing drainage improvements are shown on Figure 2 on the following page. LITTLE COOL CREEK BASIN Each drainage basin was examined briefly with regard to development or redevelopment potential based on existing conditions and the Master Plan. Currently developed areas which are already served by storm water detention or retention facilities and which are not likely to be redeveloped were felt to be poor candidates for centralized storm water controls since those parcels would not gain any added value from such efforts. Generally the areas which appeared to be most likely to redevelop were older residential parcels developed when the area was primarily rural in character, smaller business' occupying converted residential structures, and older smaller business structures. In this regard the Little Cool Creek basin is probably poorly suited for centralized detention or storage facilities since the majority of the basin is occupied by St. Vincent's hospital, and the St. Vincent's Medical Pavilion. Both of these parcels are relatively new and have individual storm water controls already in place. Only 15 acres or so of undeveloped land consisting of an existing nursery and other residential rural lots remain to be redeveloped. Based on these observations we have concluded that the Little Cool Creek basin should be eliminated from further consideration of centralized facilities. PROVIDENCE BASIN Another observation which was made regarding the drainage basins was that the boundaries between the Providence, School and Main Street basins could be easily modified due to the relatively flat topography in the area where they meet. In fact the entire portion of the Providence basin which is currently undeveloped (west of Old Meridian) could be redirected toward the School basin with the addition of storm sewers. In addition a major portion of the Main Street basin could be redirected toward the School basin. These boundary modifications are felt to be probable since that would align the basins with the anticipated street layout. This issue becomes important when considering that all portions of the Providence basin downstream of Old Meridian have just been developed and no future opportunities for development of centralized facilities will be possible. Because of this we have concluded that the Providence basin should have the upper portion redirected toward the School basin and that the lower portions of the basin should be dropped from further consideration for centralized facilities. Figure 3 presents the revised drainage basin limits. Page 5 of 14 Carmel, Indiana .R9N9l1~~~ 10289 NOVElil8ER.2000 FIGURE #2 EXISTING DRAINAGE BASINS CITY Of" CARMEL CARMEL STORMWATER EVALUATION CARAlEL. INDIANA VN'tIONI ',3rllN:> OOOZ '1I38"3MN 6aZOl NOIlVn1V^3 ~3J.VM"~OJ.S 13"~~ 13"~~ .:10 AJ.I~ lnOA V1 NISVS 39VNI~O 03SIA3H t# 3Hn91:1 03nii6iJoa. D D o o o o D o o o o o o D o o o D o Phase I Stormwater Master Plan Old Meridian Area FERTIG BASIN In the Fertig basin approximately half of the existing land has recently been developed and is generally in accordance with the overall master plan. Of the remaining undeveloped areas approximately half is currently in the plan development stage (adorn Property). Installation of a storm water storage facility on this parcel would negate the majority of any potential benefit to the basin from centralized facilities. The remaining area in the basin which is to be developed or redeveloped consists of 3 parcels which are widely separated from each other. Based on our analysis and discussions with the City Engineers office the Fertig Basin will therefore be eliminated from further consideration. MAIN STREET BASIN At the initiation of this investigation the only site in the Main Street Basin which was available and was of value from a storage standpoint was at the downstream end of the basin, along Main Street approximately 300 feet west of Guilford. The site was located on the south side of Main Street between an existing strip mall and a 2 story office building just north of the Carmel Pool complex. This site is crossed by an unnamed drainage ditch which drains the Main Street basin and would therefore result in minimal improvements for conveyance facilities into the storage basin. During the preparation of this report the selected parcel was approved for an apartment development. Since this site was the only feasible site in the Main Street Basin development of centralized storage would probably not be feasible unless some of the flows were diverted into one of the adjoining School basins and stored there. After discussion with the City Engineers office it was determined that the Main Street Basin should be dropped from further consideration of centralized storage. COLLINS BASIN The Collins basin is currently served by a field tile which is located in the Collins legal drain, and by 2 drainage culverts crossing under Rt. 31 on the north and south sides of 131 st Street (Main Street). The low points in the basin are at the drainage culverts and placement of regional storage facilities at any other location would be impractical. Although the storage sites are on prime property with frontage on Rt.31 and 131 st Street they are the only available sites. Since the Collins basin is relatively small anyway and the locations of potential storage are limited by existing grades it is recommended that the developers of those parcels be responsible for determining and providing the storage required to best suit their proposed developments. As such the Collins basin should be deleted from further consideration. SCHOOL BASIN Following review of the School Basin it was determined to be potentially suitable for centralized storage. A future conditions rainfall runoff hydrograph was developed for the School Basin to estimate the volume of storm water to be retained to comply with the current storm water requirements of the City. The current requirements are to provide adequate storage volume to store the runoff expected after full development from a 100 year storm event reduced by the amount released under natural conditions. For the purposes of the calculations a natural condition is the 10 year storm event with a runoff coefficient of 0.15 (predevelopment conditions). Page 8 of 14 Carmel, Indiana U D D D D D D D D D D D D D D D D D D Phase I StOn1lwater Master Plan Old Meridian Area The School Basin runoff hydrograph was developed based on the 10 and 100 year storm intensities for the Indianapolis area at various times of concentration and the corresponding areas contributing to the basin discharge point at the time of concentration being evaluated. The hydro graph and the data upon which the hydrograph was formed are attached to this report as Appendix A. Note that although the School parcel itself is approximately 40 acres only 25 acres are estimated to be able to get to a storage basin on site due to the existing drainage configurations. The results of the calculations are shown in Table 2 below. As seen in the table approximately 18 acft of storage would be required for current conditions according to the current regulations and an additional 20 acft are needed for the future development. Table 2 School Basin Dischar e Rates and Stora SCHOOL BASIN STORAGE SITES Potential storage basin sites were then selected based on the drainage patterns and availability of property on which to construct such facilities. Figure 4 indicates the locations of the storage facilities. The 3 basins shown in the School drainage basin are identified as A, B, and C for ease of discussion. Only one site is needed for storage however, as discussed below. All three sites selected for potential storage are generally open fields without permanent improvements with the exception of the eastern portion of Site C which has the existing pool complex on it (which we understand will be removed in the near future). Each of the potential sites on the School property also has some design difficulties or cost implications associated with it. Site A is acceptable to the School District but has limited depth for gravity discharge and is located the furthest from the discharge point. These factors will may make it more costly to construct and operate. Site B, as we learned late in the report preparation will not be acceptable to the School District and therefore cannot be used even though it is well situated and could be entirely concealed below grade. Site C is somewhat elevated from the others, and therefore probably cannot collect stormwater flows from the adorn Woods area and the southern portions of the School Property itself without excessive excavation. Because of these limitations on Site C, the tributary areas and time of concentration for the Site C basin should be revised. The revised calculations appear in Appendix B and are summarized in Table 3 below. Table 3 e Rates and Stora Page 9 of l4 Carmel, Indiana YNYlQNI '1311llW':> OOOZ'1I38n3^ON 68Z01 NOI.1VnlV^3 ~3.1VMt"i~0.1S '3t"i~J '3t"i~J .:10 )'.1IJ SNOI.L VOO, NISVB 3E>\fHO.LS 'VI.LN3.LOd t# 3HnE>l:I 03ni-ioNoa{((f I" I I "" u u o o D D D D D D D D D o o D D D o Phase I Stormwater Master Plan Old Meridian Area One additional school site that is also possible is the woodland area that is currently used as an outdoor classroom (adorn Woods). However, the site contains numerous large old trees and will probably be one of the few remaining undeveloped parcels in the area in the future. We believe that public and school district opposition to construction of storage facilities on that site would be substantial and may not be in the City's interest to pursue initially, although we would suggest that site as an alternate to the remaining two sites identified if neither of those sites can be used. Both of the available sites on the elementary and Jr. High properties are currently open athletic fields. It should be possible to utilize either of the sites with proper coordination efforts and allowance during design for compatible uses. We recommend either Site A or C on the School property since both are useable and of equal value for storage although each site has unique cost and design disadvantages. Storage Site A contains approximately 4.25 acres and would require a water depth of 9 feet to accommodate the anticipated volume. Storage Site C is approximately 4.2 acres in size and would require a water depth of 5.25 feet to accommodate the anticipated volume. Lessor depths and potential cost reductions can be achieved if the City elects to only provide storage for the growth component of the flows rather than for the entire calculated amount. COST ESTIMATES The costs for the storage basins to be provided are dependant to a large degree on the type of storage facility provided. The major types of storage facilities which are possible are dry bottom surface basins known as detention facilities, wet bottom surface basins known as retention facilities, and subsurface storage facilities. Most common are detention and retention basins due to their low construction and maintenance costs. The major cost difference is the cost of additional excavation in retention basins to provide the retained water pool volume. Often this cost is justified by the need for additional fill material at some location or for aesthetic purposes. Subsurface storage facilities can be constructed of box culverts, large diameter pipes, precast or cast-in-place concrete, and other materials which are beginning to come to the marketplace for such purposes. Normally they are placed under parking lots or other non-structural surface improvements which makes them accessible for maintenance or repairs. Subsurface facilities can be either gravity drained or pumped depending on the available elevation drop on the site and the elevation at which the facility can be constructed. For gravity drained and pumped subsurface facilities provisions for cleaning and removing accumulated sediment also have to be included. While any of the three types of facilities can be constructed in the areas selected for the storage facilities, the least expensive construction method would be for the dry bottom surface basin. This type of basin would represent the least possible cost from a feasibility standpoint, and therefore if the cost were felt to be too high, it could be concluded that it was not feasible to provide centralized storage for the basin. We have therefore provided the cost for dry bottom surface basins in this phase. For Site A we have included costs for pumping the bottom 6 feet of the basin to enable the site to be used. For Site C we have included the cost of overexcavating the upper 5 feet of the area to enable flows to enter the basin by gravity. Discharge is anticipated to be by gravity also. Since this is the first phase of a two phase project further cost refinements Page I J of 14 Carmel, Indiana D D D D U D D D D D D D D o D D D D U Phase I Stormwater Master Plan Old Meridian Area and costs of additional options are to be provided in the phase 2 work when more information is known regarding the type of basin potentially desired. The total cost for the two dry bottom storage facilities is summarized in the following table 4. The costs include a 20% contingency amount, and an additional 25% of construction cost for design, administration, legal and financial costs that will likely be incurred. Appendix D contains complete copies of the cost estimates. Table 4 Estimated Construction Costs for Stora e Basin Facilities The costs presented above are anticipated to be initially expended by the City in order to construct the storage facilities and then be recovered from the property developers/redevelopers as the areas tributary to each basin are developed. Areas which may drain into the basins but are not able to be developed such as the School property or Odom Woods were not included in the cost per acre calculations. The above costs can be reduced somewhat by minimizing the storage volume provided to that amount in excess of current conditions. This impacts Basin A most dramatically since approximately 18 acft of storage could be eliminated. This could reduce the project cost by approximately $500,000 simply by eliminating excavation quantities. An additional cost incurred with installing the storage facilities is the cost of constructing the appropriately sized major conveyance facilities which will convey flows from within the basin to the storage facilities. The need for City expenditures for upgrades to the existing conveyance systems is not included but is anticipated to be minor or not a City cost. The majority of the existing School Basin conveyance is largely overland with few structural improvements, and the anticipated future peak flows are only marginally higher. It is therefore anticipated that existing drainage patterns will largely be maintained until redevelopment occurs and that individual property owners will be responsible for upgrading conveyance systems across their property in accordance with their design plans. It is anticipated however, that funding for conveyance facilities would be needed to direct flows into either Site A or C on the School property from the property boundry. Depending on the site selected the cost could vary somewhat. We estimate that funding for such improvements would be on the order of $300,000 in construction costs for Site A and $200,000 for Site C. Those costs have been included in the estimates. Page 12 of 14 Carmel, Indiana D U D D o o o D D D D D D D D D o o o Phase I Stormwater Master Plan Old Meridian Area RECOMMENDA TIONS FACILITIES RECOMMENDED Based on the information currently available and the evaluations performed we recommend that only the School Basin be identified as an area where redevelopment activities should be allowed to occur using a centralized storm water storage concept. At this time it is not possible to select one storage site (A or C) for recommendation because alternative design configurations, which may result in differing costs, have not been evaluated. Therefore our recommendation is that either Storage Basin A or C be developed if the rough magnitude of the cost per developable acre are judged to be reasonable. FuTURE RECOMMENDED ACTIVITIES The following actions are recommended to implement the above recommendation for construction of centralized storage facilities in the School Basin. 1. Prepare Phase II of the Old Meridian Area Storm Water Master Plan. The Phase II report will: . Evaluate storage configuration and options in more detail for Sites A and C . Evaluate costs in more detail with additional engineering data . Select a storage site and configuration for construction . Estimate cost impact on a per acre basis for the area served . Establish preliminary design parameters 2. Initiate compliance and management activities within the City to enforce compliance with the storm water master plan for centralized storage, to avoid the onset of piecemeal development of storm water facilities in the school basin. This will ensure the overall success of the program. 3. Establish a method for apportioning the cost of improvements to the properties within the school basin. 4. Establish a funding mechanism to allow the City to construct the improvements prior to recovering the costs from property owners. 5. Budget for final design of the improvements and construction. INTERIM RECOMMENDATION STORM WATER CULVERT IMPROVEMENT CROSSING OLD MERIDIAN STREET During the preparation of this report planning and design of paving improvements to Old Meridian in accordance with the overall Master Plan was initiated. The improvements included storm water conveyance facilities across Old Meridian from upper parts of the School, Main and Providence Basins. Because the School Basin is proposed to be enlarged with the addition of portions of the Main and Providence Basins, additional capacity was judged to be needed where the School drainage basin would convey flow across Meridian. To develop the culvert size required the rational method was utilized with the additional areas included. The result of the evaluations was that a concrete 48-inch or equivalent pipe was needed instead of the existing 24- inch culvert. Correspondence dated 3/12/2001 from the Indiana Department of Transportation Page /3 of 14 Carmel, Indiana u u u u o D D D D D D D D D D D D D D Phase I Stormwater Master Plan Old Meridian Area indicates that a 1.65 m X 1.01 m (65 X 40 inch) CMP Arch culvert is planned for the crossing location. Calculations for sizing the 48-inch equivalent size are included in Appendix C. Figure 5 on the following page presents the proposed improvement and the anticipated flow paths along proposed roadways leading to the culvert. Page 14 of 14 Carmel, Indiana \- i r I r. i [:::::::J I ,-J r - l r I r 1 r 1 r .] I 1 I 1 I .1 1--] l=J [ ~-l 1--- l I l r l .~9l'l9lt~~@ FIGURE #5 INTERIM RECOMMENDATION CULVERT UNDER OLD MERIDIAN CITY OF CARMEL CARMEL STORMWATER EVALUATION u u u u U D U D D U U D o o D o o \U U, Phase I Storm water Master Plan Old Meridian Area Appendix A School Basin Runoff and Storage Calculations Carmel, Indiana D D Calculation 01 Storm System Storage Requirements School Basin Existing D Existing Development Coefficient Subbasin Factor D D Wei, lied Coelficienl 0.289 Undeveloped Coefficient Approximate Time of Concentration Tc (hr) Undeveloped 10 Year Intensity @ Tc Undeveloped Row Rate (CFS) D Tc o D D School Basin Proposed D Pro ed Development Coefficient Subbasin Factor D D Developed Coefficient Developed Time of Concentration T c (hr) Developed 100 Year Intensity @ Tc Developed Row Rate (CFS) D Tc D o D D D o 7.78 5.99 4.84 3.03 1.87 1.42 1.15 0.85 0.67 0.48 0.34 0.27 64 105 133 129 87 66 53 39 31 22 16 13 0 D D 0 0 17.421 640.851 D 17.421 606.010 17.421 571.169 17.421 536.327 ...; 480.581 459.677 0 438.772 417.867 250 0 260 95.000 0.489 1.100 51.101 15.818 5.807 352.830 270 95.000 0.489 1.075 49.939 15.818 5.807 341.216 280 95.000 0.489 1.050 48.778 15.818 5.807 329.603 290 95.000 0.489 1.025 47.616 15.818 5.807 317.989 300 95.000 0.489 1.000 48.455 15.818 5.807 306.375 310 95.000 0.489 0.975 45.294 15.818 5.807 294.761 0 320 95.000 0.489 0.950 44.132 15.818 5.807 283.148 330 95.000 0.489 0.925 42.971 15.818 5.807 271.534 340 95.000 0.489 0.900 41.810 15.818 5.807 259.920 350 95.000 0.489 0.875 40.648 ~5.818 .7JEl D 370 95.000 0.489 0.835 38.790 15.818 3.484 229.724 380 95.000 0.489 0.820 38.093 15.818 3.484 222.756 390 95.000 0.489 0.805 37.396 15.818 3.484 215.786 400 95.000 0.489 0.790 36.699 15.818 3.484 208.820 410 95.000 0.489 0.775 36.003 15.818 3.484 201.851 420 95.000 0.489 0.760 35.306 15.818 3.484 194.883 D 430 95.000 0.489 0.745 34.609 15.818 3.484 187.915 440 95.000 0.489 0.730 33.912 15.818 3.484 180.947 450 95.000 0.489 0.715 33.215 15.818 3.484 173.978 460 95.000 0.489 0.700 32.519 15.818 3.484 167.010 470 95.000 0.685 31.822 15.818 3.484 160.042 D 490 95.000 0.489 0.662 30.757 15.818 1.839 149.396 500 95.000 0.489 0.654 30.389 15.818 1.839 145.718 510 95.000 0.489 0.646 30.022 15.818 1.839 142.040 520 95.000 0.489 0.838 29.654 15.818 1.839 136.363 530 95.000 0.489 0.630 29.286 15.818 1.839 134.685 0 540 95.000 0.489 0.623 28.918 15.818 1.839 131.007 550 95.000 0.489 0.615 28.550 15.818 1.839 127.330 560 95.000 0.489 0.607 28.183 15.818 1.839 123.652 570 95.000 0.489 0.599 27.815 15.818 1.839 119.974 580 95.000 0489 0.591 27.447 15.818 1.839 116.297 0 590 95.000 0.489 0.583 27.079 15.818 1.839 112.619 600 95.000 0.489 0.575 26.712 15.818 1.839 108.941 610 95.000 0.489 0.567 26.344 15.818 1.839 105.264 620 95.000 0.489 0.559 25.976 15.818 1.839 101.586 630 95.000 0.489 0.551 25.608 15.818 1.839 97.908 640 95.000 0.489 0.543 25.241 15.818 1.839 94.231 D 650 95.000 0.489 0.535 24.873 15.818 1.839 90.553 660 95.000 0.489 0.528 24.505 15.818 1.839 86.875 670 95.000 0.489 0.520 24.137 15.818 1.839 83.197 680 95.000 0.489 0.512 23.769 15.818 1.839 79.520 690 95.000 0.489 0.504 23.402 15.818 1.839 75.842 700 95.000 0.489 0.496 23.034 15.818 1.839 72.164 D 710 95.000 0.489 0.488 22.666 15.818 68.487 0 D 0 D D D School Basin Pro sed Conditions Runoff Rate /CFSI Allowable Area A (triangle Area B (rectangle To Area (Ac) Coefficient C Intensity Flow Rate Rate under curve) under curve) 730 95.000 0.489 0.476 22.118 15.818 0.903 63.002 740 95.000 0.489 0.472 21.937 15.818 0.903 61.196 750 95.000 0.489 0.488 21.756 15.818 0.903 59.389 760 95.000 0.489 0.484 21.576 15.818 0.903 57.583 770 95.000 0.489 0.481 21.395 15.818 0.903 55.776 780 95.000 0.489 0.457 21.214 15.818 0.903 53.970 790 95.000 0.489 0.453 21.034 15.818 0.903 52.163 800 95.000 0.489 0.449 20.853 15.818 0.903 50.356 810 95.000 0.489 0.445 20.672 15.818 0.903 48.550 820 95.000 0.489 0.441 20.492 15.818 0.903 48.743 830 95.000 0.489 0.437 20.311 15.818 0.903 44.937 840 95.000 0.489 0.433 20.131 15.818 0.903 43.130 850 95.000 0.489 0.429 19.950 15.818 0.903 41.323 860 95.000 0.489 0.426 19.769 15.818 0.903 39.517 870 95.000 0.489 0.422 19.589 15.818 0.903 37.710 880 95.000 0.489 0.418 19.408 15.818 0.903 35.904 890 95.000 0.489 0.414 19.227 15.818 0.903 34.097 900 95.000 0.489 0.410 19.047 15.818 0.903 32.291 910 95.000 0.489 0.406 18.866 15.818 0.903 30.484 920 95.000 0.489 0.402 18.685 15.818 0.903 28.677 930 95.000 0.489 0.398 18.505 15.818 0.903 26.871 940 95.000 0.489 0.394 18.324 15.818 0.903 25.084 950 95.000 0.489 0.391 18.143 15.818 0.903 23.258 960 95.000 0.489 0.387 17.963 15.818 0.903 21.451 970 95.000 0.489 0.383 17.782 15.818 0.903 19.644 980 95.000 0.489 0.379 17.601 15.818 0.903 17.838 990 95.000 0.489 0.375 17.421 15.818 0.903 16.031 1000 95.000 0.489 0.371 17.240 15.818 0.903 14.225 1010 95.000 0.489 0.367 17.059 15.818 0.903 12.418 1020 95.000 0.489 0.363 16.879 15.818 0.903 10.612 1030 95.000 0.489 0.359 16.698 15.818 0.903 8.605 1040 95.000 0.489 0.356 16.517 15.818 0.903 6.998 1050 95.000 0.489 0.352 16.337 15.818 0.903 5.192 1060 95.000 0.489 0.348 16.156 15.818 0.903 3.385 1070 95.000 0.489 0.344 15.975 15.818 " iin:~;'",,"" 1090 95.000 '0.489 0.338 15.704 15.818 1100 95.000 0.489 0.336 15.614 15.818 1110 95.000 0.489 0.334 15.524 15.818 1120 95.000 0.489 0.332 15.433 15.818 1130 95.000 0.489 0.330 15.343 15.818 1140 95.000 0.489 0.328 15.253 15.818 1150 95.000 0.489 0.326 15.162 15.818 1160 95.000 0.489 0.324 15.072 15.818 1170 95.000 0.489 0.323 14.982 15.818 1180 95.000 0.489 0.321 14.891 15.818 1190 95.000 0.489 0.319 14.801 15.818 1200 95.000 0.489 0.317 14.711 15.818 1210 95.000 0.489 0.315 14.620 15.818 1220 95.000 0.489 0.313 14.530 15.818 1230 95.000 0.489 0.311 14.440 15.818 1240 95.000 0.489 0.309 14.349 15.818 1250 95.000 0.489 0.307 14.259 15.818 1260 95.000 0.489 0.305 14.169 15.818 1270 95.000 0.489 0.303 14.078 15.818 1280 95.000 0.489 0.301 13.988 15.818 1290 95.000 0.489 0.299 13.898 15.818 1300 95.000 0.489 0.297 13.807 15.818 1310 95.000 0.489 0.295 13.717 15.818 1320 95.000 0.489 0.293 13.627 15.818 1330 95.000 0.489 0.291 13.536 15.818 1340 95.000 0.489 0.289 13.446 15.818 1350 95.000 0.489 0.288 13.358 15.818 1360 95.000 0.489 0.286 13.265 15.818 1370 95.000 0.489 0.284 13.175 15.818 1380 95.000 0.489 0.282 13.085 15.818 1390 95.000 0.489 0.280 12.994 15.818 1400 95.000 0.489 0.278 12.904 15.818 1410 95.000 0.489 0.276 12.814 15.818 1420 95.000 0.489 0.274 12.724 15.818 1430 95.000 0.489 0.272 12.633 15.818 D D o D D D D D o D D D D 975.901 26677.67 Total Volume = 1,659,214.386 CF Area of pond with 9 It depth = 4.232 Acres or 38.090 AcFt D D o u u 0 O~ :6.1 0 OcQ (!'.1 O~ .I 0(2 0 (!'.1 0& C} Oc? .I 00> D .1.1 0:6 .1.1 00 '.1.1 D 0& V.I o~ 0.1 0& (5' 0 OA (5' 0(2 15' O,s! 0 0> .c O~ en Q, c9 CI) CCI 00>< ... .. :J tJ) OA C 0 0 :i .. < "C o~ .5 >- '<' CI) X 061 E \9 0 C ~ i= .; CCI oa m 19 0 '0 <:?9,9 0 o~ .c ~ () Oo>A en D ~ <:VA <?9C' D O~ C' qp~ ~~ 0 <:V~ 0.9.1 0 O~ .I 00> OA 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ~ 0 0 ~ ~ C! 0 0 ci 0 ci ci 0 0 0 ci ci <0 -:t t\I 0 CO <0 -:t t\I ..... ..... D 5:1::> U! MOI:l 0 u o D D o D D D D o Q o o D o D U o U Phase I Stormwater Master Plan Old Meridian Area Appendix B School Basin Site C Runoff and Storage Calculations Carmel, Indiana u u Calculation of Storm System Storage Requirements Site C School Basin Existing o D Existing Development Coefficient Subbasin Factor o Wei hted Coefficient 0.234 Undeveloped Coefficient Approximate Time of Concentration Tc (hr) Undeveloped 10 Year Intensity @ Tc Undeveloped Flow Rate (CFS) 0.234 "..'::'<:',:~:i~;~~l~:~; 22.06138 u Exlstln School Basin Runoff Rate CFS Tc Area Ac Coefficient C Intensi! Flow Rate o 7.78 5.99 4.84 3.03 1.87 1.42 1.15 0.85 0.67 0.48 o D School Basin Proposed D 0.541 Subbasin Factor 3 1 27 8 o o o o 0.540 Developed Coefficient Developed Time of Concentration Tc (hr) Developed 100 Year Intensity @ Tc Developed Flow Rate (CFS) 95.13045 D Tc o 7.78 5.99 4.84 3.03 1.87 1.42 1.15 0.85 0.67 0.48 0.34 0.27 D D o o D 35 37 45 45 31 24 19 14 11 8 47 90 113 113 71 54 44 32 26 18 13 10 0 D U D 34.089 772.619 D 34.393 703.833 34.698 634.437 35.002 564.433 ~I~l1*;. ~1ia1l11~ 14.327 465.166 14.327 436.512 D 14.327 407.859 14.327 379.205 14.327 :"4Y~ 52.532 22.061 8.596 50.813 22.061 8.596 287.513 0 49.093 22.061 8.596 270.321 47.374 22.061 8.596 253.128 45.655 22.061 ...... 250 70.750 0.540 42.981 22.061 D 260 70.750 0.540 1.100 42.026 22.061 4.776 199.641 270 70.750 0.540 1.075 41.070 22.061 4.776 190.090 280 70.750 0.540 1.050 40.115 22.061 4.776 180.539 290 70.750 0.540 1.025 39.160 22.061 4.776 170.988 300 70.750 0.540 1.000 38.205 22.061 4.776 161.436 310 70.750 0.540 0.975 37.250 22.061 4.776 151.885 D 320 70.750 0.540 0.950 36.295 22.061 4.776 142.334 330 70.750 0.540 0.925 35.340 22.061 4.776 132.783 340 70.750 0.540 0.900 34.385 22.061 4.776 123.231 350 70.750 22.061 4.776 U 370 70.750 0.835 31.901 22.061 2.665 98.398 380 70.750 0.540 0.820 31.328 22.061 2.865 92.667 390 70.750 0.540 0.805 30.755 22.061 2.865 86.937 400 70.750 0.540 0.790 30.182 22.061 2.865 81.206 410 70.750 0.540 0.775 29.609 22.061 2.865 75.475 420 70.750 0.540 0.760 29.036 22.061 2.865 69.744 D 430 70.750 0.540 0.745 28.463 22.061 2.865 64.014 440 70.750 0.540 0.730 27.890 22.061 2.865 58.283 450 70.750 0.540 0.715 27.317 22.061 2.865 52.552 460 70.750 0.540 0.700 26.744 22.061 2.865 46.821 470 0.540 0.685 22.061 D 70.750 0.540 0.682 25.295 22.061 32.335 500 70.750 0.540 0.654 24.992 22.061 1.512 29.311 510 70.750 0.540 0.646 24.690 22.061 1.512 26.286 520 70.750 0.540 0.638 24.388 22.061 1.512 23.282 530 70.750 0.540 0.830 24.085 22.061 1.512 20.237 0 540 70.750 0.540 0.823 23.783 22.061 1.512 17.212 550 70.750 0.540 0.615 23.480 22.061 1.512 14.188 560 70.750 0.540 0.607 23.178 22.061 1.512 11.163 570 70.750 0.540 0.599 22.875 22.061 1.512 8.139 560 70.750 0.540 0.591 22.573 22.061 1.512 5.114 0 590 70.750 0.540 0.583 22.270 22.061 0.722 600 70.750 0.540 0.575 21.968 22.061 610 70.750 0.540 0.587 21.665 22.061 820 70.750 0.540 0.559 21.363 22.061 630 70.750 0.540 0.551 21.061 22.061 640 70.750 0.540 0.543 20.758 22.061 0 650 70.750 0.540 0.535 20.456 22.061 660 70.750 0.540 0.528 20.153 22.061 670 70.750 0.540 0.520 19.851 22.061 680 70.750 0.540 0.512 19.548 22.061 690 70.750 0.540 0.504 19.246 22.061 D 700 70.750 0.540 0.496 18.943 22.061 710 0.488 22.061 787.018 15232.60 Total Volume = 961.189.216CF D Area of pond with 5.25 It depth = 4.203 Acres or 22.066 AcFt 0 D u 0 o~ ~ 00 ~ 0 061 <9 ~.9 0 ~ Odl .,g Oa <9 0 061 ~ 0& ~ 0 0,6 ~ Odl ~ q,,r 0 00>,6 0.9,6 D .c 0A.,s c. CO o~ ~ C) I/) 00,6 Cl) 0 ... 0 ~ :J 'C 061 .5 >- C!' == :I: 0& .5 C C' Cl) 0 U) o~ E CO j:: m odl "0 c!' 0 0 q,c> .c 0& () UJ ~ 0 0& ~ U s 0,6 Ci) ~ o~ ~ 0 q,~ 00>.... 0.9.... 0 0,6.... Oc} 0 00.... 00> 0.9 0 0,6 o~ 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ~ 0 0 0 0 ci 0 ci 0 ci ci ci ci "<t C\l 0 co CD "<t C\l ,... T"" ,... 0 S:l~ U! MOI:l 0 u o -0 D D o o o o D o o u o D D D U o Phase I Stormwater Master Plan Old Meridian Area Appendix C Interim Recommendation Calculations Carmel, Indiana u o o o D o D D D D D D D o D D D U U Concrete Pipe Crossing Acres Developed Coefficient Developed Time of Concentration T c (hr) Developed Intensity @ T c Developed Flow Rate (CFS) mannings equation "n" value size in ft slope flow Corrugated Metal Pipe Crossing Acres Developed Coefficient Developed Time of Concentration T c (hr) Developed Intensity @ Tc Developed Flow Rate (CFS) mannings equation "n" value Equivalent Metal Pipe size in ft slope flow upper school basin under Old Meridian 44.75 0.6 .~i63.... 81.3555 0.013 4 0.005 101.5711392 upper school basin under Old Meridian 44.75 0.6 lower school to basin C All School basin 70.8 110 0.54 0.5 1>.25 1.5 g.49 2:24 95.19768 123.2 0.013 0.013 4 4.5 0.005 0.005 101.5711392 139.0573986 lower school to basin C All School basin 70.8 110 0.54 0.5 81.3555 0.022 4.5 0.005 82.170281 95.19768 0.022 5 0.005 108.8303434 2:24 123.2 0.022 5.5 0.005 140.3279855 U D D U D D o U D D D o o o D D o U o Phase I Storm water Master Plan Old Meridian Area Appendix D Conceptual Cost Estimates Carmel, Indiana U D D D D D o D D D o iD o o D o U o D Storage Basin Cost Estimate School Site A Drv Bottom Storage Basin Item Quantity Units Unit Price Item price Clearing Brush, Stripping and Stockpiling Topsoil 204000 SF $ 0.25 $ 51,000 Influent Piping from Odom Woods area, End Sections, Rip Rap 1 LS $ 300,000.00 $ 300,000 Effluent Piping connection 1 LS $ 2,000.00 $ 2,000 Pumped Discharge 1 LS $ 100,000.00 $ 100,000 Excavation and Embankment/Disposal 45254 CY $ 10.00 $ 452,540 Underdrains @ 20' Centers 8800 LF $ 7.50 $ 66,000 Topsoil and Seeding 204000 SF $ 0.50 $ 102,000 Miscellaneous Surface Improvements 1 LS $ 50,000.00 $ 50,000 Mobilization and Proiect Administration @ 1 0% 1 LS $ 112,400.00 $ 112,400 Rounded Subtotal $ 1,236,000 Contingency @ 20% $ 247,200 Design, Legal, Admin, Financial @25% $ 309,000 Total $ 1,792,200 Estimated Developable Acres (not including Odom Woods or School Property) $ 29,574 60.6 Cost/Acre u u u u u o U D o U D U D o U D U U o Storage Basin Cost Estimate School Site C Drv Bottom Storaae Basin Item Quantity Units Unit Price Item price Clearing Brush, Stripping and Stockpiling Topsoil 120000 SF $ 0.25 $ 30,000 Tennis Court and Pool Facilities Demolition 1 LS $ 100,000.00 $ 100,000 Influent Piping from Upstream Ditch, End Sections, Rip Rap 1 LS $ 200,000.00 $ 200,000 Effluent Piping, End Sections, Rip Rap 1 LS $ 10,000.00 $ 10,000 Excavation and Embankment/Disposal (includes 5 ft surface excavation) 76399 CY $ 10.00 $ 763,990 Underdrains @ 20' Centers 10075 LF $ 7.50 $ 75,563 Topsoil and Seeding 202000 SF $ 0.50 $ 101,000 Miscellaneous Surface Improvements 1 LS $ 50,000.00 $ 50,000 Mobilization and Proiect Administration @1 0% 1 LS $ 128,100.00 $ 128,100 Rounded Subtotal $ 1 ,458,700 Contingency @ 20% $ 291,700 Design, Legal, Admin, Financial @25% $ 364,700 Total $ 2,115,100 Estimated Developable Acres (not including Odom Woods or School Property) $ Cost/Acre 34,903 60.6