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38 High Rock Ave, Suite 3 | P.O. Box 272 | Saratoga Springs, NY 12866 | 518.450.4030 STORMWATER MANAGMENT NARRATIVE Project: Civitella Residence Date: December 15, 2021 Project Background: The project site is a 0.39 acre, or 16,813 square feet, parcel adjacent to Lake George, located at the terminus of Knox Road. The address is 104 Knox Road, Tax Map ID 293.-1-20, in the Town of Queensbury and the parcel is zoned as Waterfront Residential. The existing site is composed of an existing compacted soil driveway that terminates at a cleared area with a seasonal residence, shed, and set of steps down to the lake. The woods surrounding the residence are in poor condition – no groundcovers or understory exist. The western half of the property gradually slopes towards the Lake George shoreline with slopes ranging from 5% to 15%. Within 10’ of the Mean High Water (MHW) mark, slopes are greater than 50%. The eastern half of the site slopes the site entrance with slopes ranging from 5% to 20%. The site’s soils consist exclusively of Charlton fine sandy loam, which is classified as Hydrologic Soil Group B. Details of site soils are presented in the USDA soil report provided in Appendix B of this narrative. Development: The proposed development includes demolishing the seasonal residence, the shed, the steps down to the lake, and the remains of an old dock. to construct a single-family residence, paved driveway, on- site wastewater treatment system, an on-site potable water well, permanent stormwater practices, and associated landscaping. The total disturbance area is approximately 13,439 square feet. The proposed work will create approximately 4,274 square feet of impervious area and 1,698 square feet of permeable pavers. If the permeable pavers are given 50% credit for impermeability, 5,123 square feet, or 30.6% of the site, is considered impermeable. Proposed work will primarily take place within the existing clearing, located in the center of the property. Existing trees, especially along the shoreline, will be protected to the greatest extent possible. No impermeable areas greater than 100 square feet in size are proposed within 35’ of the lake MHW mark setback. Stormwater Management: Proposed stormwater control measures include a rain garden, a gravel trench, and subsurface storage and infiltration below the permeable pavers. No infiltration will take place within 35’ of the MHW mark for Lake George. Additionally, no infiltration practices are proposed with 20’ of the on-site wastewater treatment absorption field, not within 25’ of the proposed well. Impermeable liners will be installed under the permeable pavers and gravel trench to protect water quality and these practices will solely serve as stormwater storage. In addition to the permanent control measures, temporary erosion and sediment control measures will be installed and maintained throughout the duration of construction in accordance with the New York State Stormwater Management Design Manual, January 2015 and the New York Standards and Specifications for Erosion and Sediment Control. Refer to the construction drawings L-0.30, L-1.10, and L-2.10 for the locations and details of the proposed stormwater features. The post-construction site was broken up into five subcatchment areas with two design points – one design point to the east (the entrance) and the other design point to the west (Lake George). To the east, the proposed subcatchments are 1S and 3S, which consist of a portion of the roof, permeable pavers, an asphalt driveway, lawn area, and newly landscaped areas. In 1S a gravel trench catches and stores runoff from upland areas, including the asphalt driveway. An impermeable liner will be installed along the trench to ensure infiltration does not occur with 20’ of the wastewater absorption field. Overflow runoff will flow off-site to follow existing drainage conveyances. In 3S, permeable pavers attenuate runoff from the roof and paver area in 12” of gravel storage. This 12” depth provides enough stormwater storage to provide 1.5 gallons/ square foot of roof and pavers in this subcatchment. Additionally, a gravel trench will run along the perimeter of the pavers at the lowest elevation to catch overflow from the pavers and will allow for stormwater to enter the subsurface reservoir. These design elements satisfy the Lake George Park Commission’s stormwater requirements for permeable pavers. Overflow runoff will flow to the gravel trench. To the west are subcatchments 2S, 4S, and 5S, which includes a portion of the roof, the lakeside patio lawn area, a fire pit, steps to the lake, and new landscaping. 2S consists mostly of areas heavily revegetated with native plant species, lawn, and a portion of the proposed residence’s roof. Stormwater will be treated and slowed by the revegetated areas. Detailed stormwater runoff calculations are included in Appendix D. 4S consists mostly of areas heavily revegetated with native plant species and a portion of the proposed residence’s roof. Stormwater will be conveyed to a rain garden. Overflow runoff pass through an overflow weir and flow towards the lake to follow existing drainage conveyances. Roadways, parking lots and other areas subject to vehicle traffic will not convey to this rain garden, therefore a 100’ setback from the shoreline for this infiltration practice is not required. The Lake George Park Commission requires a 35’ setback from infiltration practices to the MHW mark, which is included in the proposed design. Runoff from 5S, which includes a portion of the roof, will sheet flow to permeable pavers with 9” of gravel storage. This 12” depth provides enough stormwater storage to provide 1.5 gallons/ square foot of roof and pavers in this subcatchment. Additionally, a gravel trench will run along the perimeter of the pavers at the lowest elevation to catch overflow from the pavers and will allow for stormwater to enter the subsurface reservoir. This paver system will have an impermeable liner to ensure water quality of the well is protected. Overflow runoff will flow towards the lake to follow existing drainage conveyances. Town of Queensbury code requires stormwater for minor residential projects be attenuated at 1.5 gallons/newly created impervious areas. The Town of Queensbury has also adopted the Lake George Park Commission’s Stormwater Management Program, which requires post-development conditions to match or reduce runoff from pre-development conditions under the 25-year storm or attenuate 1.5 gallons/newly created impervious areas, whichever is greater. Both conditions were calculated and it was determined meeting the 1.5 gallons/newly created impervious area was greater. Calculations on drawing SC-2 show how Studio A has met this criteria in the design. The method explained below explains how Studio A calculated the 25-year storm event. The design storm event was assumed to be customized storm curves based upon Extreme Precipitation Data in New York & New England available through a joint collaboration between the Northeast Regional Climate Center and Natural Resources Conservation Service for Type II storm events. The rainfall magnitude for the 25-year storm events was determined to be 4.26 inches. The runoff rates were modeled using HydroCAD version 10.0 software which calculates runoff based on the modified SCS TR-20 method. The peak runoff discharge passing through the proposed stormwater management system will be attenuated to be less than or equal to the pre-development flow rates for the 25-year 24-hour storm at established discharge design points. The peak off-site discharge rate for the 24-hour 25 year is as follows: Pre-Construction (Cubic Feet/Second) Post-Construction (Cubic Feet/Second) Design Point #1 0.55 0.30 Design Point #2 0.76 0.29 MAINTENANCE OF STORMWATER MANAGEMENT SYSTEM Stormwater drainpipes shall be routinely checked for clogging to ensure proper drainage. If spaces between the permeable pavers fill with debris, the pavers shall be vacuum cleaned and new fill between the pavers shall be applied. Should the vegetated swale fill with debris, the swale shall be excavated to the original design depth. In addition to the maintenance of the stormwater practices described, the lawns and landscaped areas shall be maintained in good condition to prevent erosion. Any deteriorated areas of lawn shall be re-seeded, and a stable turf shall be reestablished. Additionally, the property owner shall provide arrangements for the future maintenance of the post- construction stormwater control measures in accordance with the Sample Stormwater Control Facility Maintenance Agreement (see Appendix A ) to be recorded in the office of the County Clerk or its terms shall be incorporated into covenants appearing in the deed, declarations of covenants and restrictions or other such documents to ensure that record notice of its terms is provided to future owners of the site. If you have any questions, please contact the undersigned at (518) 450-4030. Sincerely, Matthew E. Huntington, PE Principal For Studio A | Landscape Architecture + Engineering APPENDIX A STORMWATER MAINTENANCE AGREEMENT STORMWATER MANAGEMENT 147 Attachment 5 SCHEDULE E Sample Stormwater Control Facility Maintenance Agreement Whereas, the Town of Queensbury ('municipality') and (the "facility owner") want to enter into an agreement to provide for the long term maintenance and continuation of stormwater control measures approved by the municipality for the below named project, and Whereas, the municipality and the facility owner desire that the stormwater control measures be built in accordance with the approved project plans and thereafter be maintained, cleaned, repaired, replaced and continued in perpetuity in order to ensure optimum performance of the components. Therefore, the municipality and the facility owner agree as follows: 1. This agreement binds the municipality and the facility owner, its successors and assigns, to the maintenance provisions depicted in the approved project plans which are attached as Schedule A of this agreement. 2. The facility owner shall maintain, clean, repair, replace and continue the stormwater control measures depicted in Schedule A as necessary to ensure optimum performance of the measures to design specifications. The stormwater control measures shall include, but shall not be limited to, the following: drainage ditches, swales, dry wells, infiltrators, drop inlets, pipes, culverts, soil absorption devices and retention ponds. 3. The facility owner shall be responsible for all expenses related to the maintenance of the stormwater control measures and shall establish a means for the collection and distribution of expenses among parties for any commonly owned facilities. 4. The facility owner shall provide for the periodic inspection of the stormwater control measures, not less than once in every five year period, to determine the condition and integrity of the measures. Such inspection shall be performed by a Professional Engineer licensed by the State of New York. The inspecting engineer shall prepare and submit to the municipality within 30 days of the inspection, a written report of the findings including recommendations for those actions necessary for the continuation of the stormwater control measures. 5. The facility owner shall not authorize, undertake or permit alteration, abandonment, modification or discontinuation of the stormwater control measures except in accordance with written approval of the municipality. 6. The facility owner shall undertake necessary repairs and replacement of the stormwater control measures at the direction of the municipality or in accordance with the recommendations of the inspecting engineer. 7. The facility owner shall provide to the municipality within 30 days of the date of this agreement, a security for the maintenance and continuation of the stormwater control measures in the form of a (Bond, letter of credit or escrow account). 147 Attachment 5:1 04 - 15 - 2009 QUEENSBURY CODE 8. This agreement shall be recorded in the Office of the County Clerk, County of Warren, together with the deed for the common property and shall be included in the offering plan and/or prospectus approved pursuant to _________________. 9. If ever the municipality determines that the facility owner has failed to construct or maintain the stormwater control measures in accordance with the project plan or has failed to undertake corrective action specified by the municipality or by the inspecting engineer, the municipality is authorized to undertake such steps as reasonably necessary for the preservation, continuation or maintenance of the stormwater control measures and to affix the expenses thereof as a lien against the property. 10. This agreement is effective beginning on: _________________. 147 Attachment 5:2 04 - 15 - 2009 APPENDIX B USDA SOIL REPORT United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Warren County, New YorkNatural Resources Conservation Service May 6, 2021 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 8 9 Custom Soil Resource Report Soil Map 4813070481308048130904813100481311048131204813130481314048130704813080481309048131004813110481312048131304813140608470 608480 608490 608500 608510 608520 608530 608540 608550 608560 608570 608580 608470 608480 608490 608500 608510 608520 608530 608540 608550 608560 608570 608580 43° 27' 48'' N 73° 39' 33'' W43° 27' 48'' N73° 39' 27'' W43° 27' 45'' N 73° 39' 33'' W43° 27' 45'' N 73° 39' 27'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 18N WGS84 0 25 50 100 150Feet 0 5 10 20 30Meters Map Scale: 1:570 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. 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 1:15,800. 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: Warren County, New York Survey Area Data: Version 20, Jun 11, 2020 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jun 10, 2015—Mar 29, 2017 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. Custom Soil Resource Report 10 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI ChC Charlton fine sandy loam, 8 to 15 percent slopes 1.1 83.3% Sa Saprists and Aquepts, inundated 0.0 2.7% W Water 0.2 14.0% Totals for Area of Interest 1.3 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The Custom Soil Resource Report 11 delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha-Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 12 Warren County, New York ChC—Charlton fine sandy loam, 8 to 15 percent slopes Map Unit Setting National map unit symbol: 2wh0q Elevation: 0 to 1,440 feet Mean annual precipitation: 36 to 71 inches Mean annual air temperature: 39 to 55 degrees F Frost-free period: 140 to 240 days Farmland classification: Farmland of statewide importance Map Unit Composition Charlton and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Charlton Setting Landform:Hills, ground moraines, ridges Landform position (two-dimensional):Backslope Landform position (three-dimensional):Side slope Down-slope shape:Convex, linear Across-slope shape:Convex Parent material:Coarse-loamy melt-out till derived from granite, gneiss, and/or schist Typical profile Ap - 0 to 7 inches: fine sandy loam Bw - 7 to 22 inches: gravelly fine sandy loam C - 22 to 65 inches: gravelly fine sandy loam Properties and qualities Slope:8 to 15 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat):Moderately low to high (0.14 to 14.17 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Maximum salinity:Nonsaline (0.0 to 1.9 mmhos/cm) Available water capacity:Moderate (about 6.9 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B Ecological site: F144AY034CT - Well Drained Till Uplands Hydric soil rating: No Custom Soil Resource Report 13 Minor Components Sutton, fine sandy loam Percent of map unit:5 percent Landform:Hills, ridges, ground moraines Landform position (two-dimensional):Footslope Landform position (three-dimensional):Base slope Down-slope shape:Concave Across-slope shape:Linear Hydric soil rating: No Paxton Percent of map unit:5 percent Landform:Ground moraines, drumlins, hills Landform position (two-dimensional):Backslope Landform position (three-dimensional):Side slope Down-slope shape:Convex, linear Across-slope shape:Convex Hydric soil rating: No Chatfield Percent of map unit:3 percent Landform:Hills, ridges Landform position (two-dimensional):Backslope, shoulder, summit Landform position (three-dimensional):Crest, side slope, nose slope Down-slope shape:Convex Across-slope shape:Convex, linear Hydric soil rating: No Canton Percent of map unit:2 percent Landform:Ground moraines, ridges, hills Landform position (two-dimensional):Shoulder, backslope, summit Landform position (three-dimensional):Side slope, nose slope, crest Down-slope shape:Linear, convex Across-slope shape:Convex Hydric soil rating: No Sa—Saprists and Aquepts, inundated Map Unit Setting National map unit symbol: 9xxx Elevation: 310 to 2,380 feet Mean annual precipitation: 37 to 46 inches Mean annual air temperature: 45 to 48 degrees F Frost-free period: 110 to 160 days Farmland classification: Not prime farmland Map Unit Composition Saprists and similar soils:60 percent Custom Soil Resource Report 14 Aquepts and similar soils:30 percent Minor components:10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Saprists Setting Landform:Swamps, marshes Landform position (two-dimensional):Toeslope Landform position (three-dimensional):Talf Down-slope shape:Concave Across-slope shape:Concave Parent material:Organic material Typical profile H1 - 0 to 60 inches: muck Properties and qualities Slope:0 to 1 percent Depth to restrictive feature:More than 80 inches Drainage class:Very poorly drained Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.20 to 5.95 in/hr) Depth to water table:About 0 inches Frequency of flooding:None Frequency of ponding:Frequent Available water capacity:Very high (about 23.9 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 8w Hydrologic Soil Group: A/D Hydric soil rating: Yes Description of Aquepts Setting Landform:Depressions Landform position (two-dimensional):Toeslope Down-slope shape:Concave Across-slope shape:Concave Typical profile H1 - 0 to 6 inches: mucky fine sandy loam H2 - 6 to 60 inches: sandy loam Properties and qualities Slope:0 to 3 percent Depth to restrictive feature:More than 80 inches Drainage class:Very poorly drained Capacity of the most limiting layer to transmit water (Ksat):High (1.98 to 5.95 in/hr) Depth to water table:About 0 inches Frequency of flooding:None Frequency of ponding:Frequent Available water capacity:High (about 9.6 inches) Custom Soil Resource Report 15 Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 8w Hydrologic Soil Group: A/D Hydric soil rating: Yes Minor Components Palms Percent of map unit:2 percent Landform:Swamps, marshes Hydric soil rating: Yes Greenwood Percent of map unit:2 percent Landform:Swamps, marshes Hydric soil rating: Yes Carlisle Percent of map unit:2 percent Landform:Marshes, swamps Hydric soil rating: Yes Cathro Percent of map unit:2 percent Landform:Swamps, marshes Hydric soil rating: Yes Unnamed soils Percent of map unit:2 percent Landform:Depressions Hydric soil rating: Yes W—Water Map Unit Setting National map unit symbol: 9xyb Mean annual precipitation: 37 to 46 inches Mean annual air temperature: 45 to 48 degrees F Frost-free period: 110 to 160 days Farmland classification: Not prime farmland Map Unit Composition Water:100 percent Estimates are based on observations, descriptions, and transects of the mapunit. Custom Soil Resource Report 16 APPENDIX C SUBCATCHMENT PLANS 330325320335330336 335334 333332331329328 3273343 3 3 332331 HOUSE SHED 1.4' 14.5' 10.6' Paved Drive Gravel Drive HOUSE SHED 1.4' 14.5' 10.6' Paved Drive Gravel Drive 2S 1S SAVE DATE: 12/14/2021 8:34 AMFILE NAME: Z:\Projects\2020 Projects\20058 - Civitella Residence\DWG\05_STORMWATER\20058_SWM_EXIST.dwgPLOTTED BY: HNOLLDESIGN BY:DRAWN BY:CHECKED BY:KAC/NJONJOKACPRE-CONSTRUCTION SUBCATCHMENT PLAN1 LEGEND 2S SUBCATCHMENT LABEL TIME OF CONCENTRATION FLOW PATH SUBCATCHMENT BOUNDARY DRAWING NO. PROJECT NO.PROJECTDRAWING TITLEDATE:REVISIONSDATEDESCRIPTIONSTUDIO A LANDSCAPE ARCHITECTURE + ENGINEERING, DPC MAILING: PO BOX 272 SARATOGA SPRINGS, NY 12866 OFFICE LOCATION: 38 HIGH ROCK AVE, SUITE 3 SARATOGA SPRINGS, NY 12866 (518) 450-4030 IT IS A VIOLATION OF NEW YORK STATE EDUCATION LAW FOR ANY PERSON, UNLESS THEY ARE ACTING UNDER THE DIRECTION OF A LICENSED PROFESSIONAL ENGINEER, ARCHITECT, LANDSCAPE ARCHITECT, OR LAND SURVEYOR, TO ALTER ANY ITEM IN ANY WAY. IF AN ITEM BEARING THE STAMP OF A LICENSED PROFESSIONAL IS ALTERED, THE ALTERING LICENSED PROFESSIONAL SHALL STAMP THE DOCUMENT AND INCLUDE THE NOTATION "ALTERED BY" FOLLOWED BY THEIR SIGNATURE, THE DATE OF SUCH ALTERNATION, AND SPECIFIC DESCRIPTION OF THE ALTERATION. 12/15/2021 20058CIVITELLA RESIDENCEANTONIO & MARIA CIVITELLA104 KNOX ROADQUEENSBURY, NY 12804DRAWINGS NOT FOR CONSTRUCTION DWG OFPREPARED FORDIG SAFE NOTE: THIS PLAN SET WAS DRAFTED WITHOUT THE BENEFIT OF "DIG SAFE" MARKINGS. UTILITIES SHOWN ARE NOT WARRANTED TO BE EXACT OR COMPLETE. THE CONTRACTOR SHALL CONTACT "DIG SAFE" AT 811 BEFORE COMMENCING ANY WORK AND SHALL PRESERVE EXISTING UTILITIES WHICH ARE NOT SPECIFIED TO BE REMOVED IN THIS PLAN SET. MAP REFERENCE: BASE SURVEY INFORMATION OBTAINED FROM TAX PARCEL NO. 239.7-1-20, TOWN OF QUEENSBURY, WARREN COUNTY, NEW YORK. PRODUCED BY D.L. DICKENSON ASSOCIATES ON OCTOBER 24 AND 27, 2014.07/15/21RESPONSE TO PRE-APP. COMMENTS08/11/21RESPONSE TO PRE-APP. COMMENTS12/15/21RESIDENCE AND SITE PLAN REVISEDGRAPHIC SCALE 5 10 20010 1 inch = 10 feet *TIME OF CONCENTRATION FOR SUBCATCHMENTS 1S AND 2S ASSUMED TO BE INSTANTANEOUS DUE TO THE RELATIVELY SHORT FLOW PATHS. SC-1 2 DESIGN POINT #1: Q25-YR = 0.52 CFS DESIGN POINT #2: Q25-YR = 0.76 CFS Gravel Drive50' SHORELINE BUILDING SETBACK20' SIDE YARD SETBACK 20' SIDE Y A R D S E T B A C K 35' SHORELINE BUFFER SETBACK6' SHORELINE VEGETATIVECLEARING SETBACKPROPOSED RESIDENCE F.F.E. 334.00 PROPOSED GARAGE F.F.E. 333.50 321.75 + DOCK F.F.E. 321.50 329333.25 + 333.25 + 333.50+ 333.50+ 333.50+332331330329328327327 328330329331332333334335336 33 6 335 3 3 4 332331330333 332331 330TP 1 PT 2 PT 3 TP 2 PT 1 329328327326325324323322329328327326325324323322333.50+ 333.50+ +333.50 + 329.75' + LP =333.42' Gravel DriveGravel Drive 3S 1S SAVE DATE: 12/14/2021 8:35 AMFILE NAME: Z:\Projects\2020 Projects\20058 - Civitella Residence\DWG\05_STORMWATER\20058_SWM_PROP.dwgPLOTTED BY: HNOLLDESIGN BY:DRAWN BY:CHECKED BY:KAC/NJONJOKACPRE-CONSTRUCTION SUBCATCHMENT PLAN2 DRAWING NO. PROJECT NO.PROJECTDRAWING TITLEDATE:REVISIONSDATEDESCRIPTIONSTUDIO A LANDSCAPE ARCHITECTURE + ENGINEERING, DPC MAILING: PO BOX 272 SARATOGA SPRINGS, NY 12866 OFFICE LOCATION: 38 HIGH ROCK AVE, SUITE 3 SARATOGA SPRINGS, NY 12866 (518) 450-4030 IT IS A VIOLATION OF NEW YORK STATE EDUCATION LAW FOR ANY PERSON, UNLESS THEY ARE ACTING UNDER THE DIRECTION OF A LICENSED PROFESSIONAL ENGINEER, ARCHITECT, LANDSCAPE ARCHITECT, OR LAND SURVEYOR, TO ALTER ANY ITEM IN ANY WAY. IF AN ITEM BEARING THE STAMP OF A LICENSED PROFESSIONAL IS ALTERED, THE ALTERING LICENSED PROFESSIONAL SHALL STAMP THE DOCUMENT AND INCLUDE THE NOTATION "ALTERED BY" FOLLOWED BY THEIR SIGNATURE, THE DATE OF SUCH ALTERNATION, AND SPECIFIC DESCRIPTION OF THE ALTERATION. 12/15/2021 20058CIVITELLA RESIDENCEANTONIO & MARIA CIVITELLA104 KNOX ROADQUEENSBURY, NY 12804DRAWINGS NOT FOR CONSTRUCTION DWG OFPREPARED FORDIG SAFE NOTE: THIS PLAN SET WAS DRAFTED WITHOUT THE BENEFIT OF "DIG SAFE" MARKINGS. UTILITIES SHOWN ARE NOT WARRANTED TO BE EXACT OR COMPLETE. THE CONTRACTOR SHALL CONTACT "DIG SAFE" AT 811 BEFORE COMMENCING ANY WORK AND SHALL PRESERVE EXISTING UTILITIES WHICH ARE NOT SPECIFIED TO BE REMOVED IN THIS PLAN SET. MAP REFERENCE: BASE SURVEY INFORMATION OBTAINED FROM TAX PARCEL NO. 239.7-1-20, TOWN OF QUEENSBURY, WARREN COUNTY, NEW YORK. PRODUCED BY D.L. DICKENSON ASSOCIATES ON OCTOBER 24 AND 27, 2014.07/15/21RESPONSE TO PRE-APP. COMMENTS08/11/21RESPONSE TO PRE-APP. COMMENTS12/15/21RESIDENCE AND SITE PLAN REVISEDGRAPHIC SCALE 5 10 20010 1 inch = 10 feet SC-2 2 DESIGN POINT #2: Q25-YR = 0.29 CFS DESIGN POINT #1: Q25-YR = 0.30 CFS 2S 4S 5S 1. SITE MODELED TO ATTENUATE FOR ADDITIONAL STORMWATER CREATED FROM 25 YEAR STORM IN POST DEVELOPMENT CONDITIONS TO COMPLY WITH LAKE GEORGE PARK COMMISSION REQUIREMENTS. 2. SITE MODELED TO ATTENUATE 1.5 GAL./ADDITIONAL SQUARE FOOT OF IMPERVIOUS PAVEMENT TO COMPLY WITH TOWN OF QUEENSBURY CODE, SECTION 147-11. MINOR PROJECT STORMWATER MGMT NOTES: QUEENSBURY STORMWATER STORAGE CALCULATION: EXISTING IMPERVIOUS AREA = 1198 SF (CONSERVATIVE NUMBER - DOES NOT INCLUDE COMPACTED DIRT DRIVEWAY) PROPOSED IMPERVIOUS AREA = 5972 SF (PERMEABLE PAVERS COUNTED AS 100% IMPERVIOUS, SEE AREA CALCULATIONS ON L-1.10 FOR ADDITIONAL INFORMATION) 1198 SF (EXISTING) - 5972 SF (PROPOSED) = 4774 SF (NEW IMPERVIOUS AREA) NEW IMPERVIOUS AREA X 1.5 GALLONS = 7,161 GALLONS 7,126 GALLONS = 957 CUBIC FEET REQUIRED STORAGE = 957 CUBIC FEET PROVIDED STORAGE = 1,099 CUBIC FEET AVAILABLE STORAGE BREAKDOWN: PERMEABLE PAVERS - MOTORCOURT = 395 CF PERMEABLE PAVERS PATIO = 291 CF GRAVEL TRENCH = 178 CF RAIN GARDEN = 235 CF LEGEND 2S SUBCATCHMENT LABEL TIME OF CONCENTRATION FLOW PATH SUBCATCHMENT BOUNDARY *TIME OF CONCENTRATION FOR SUBCATCHMENTS 1S AND 2S ASSUMED TO BE INSTANTANEOUS DUE TO THE RELATIVELY SHORT FLOW PATHS. APPENDIX D STORMWATER CALCULATIONS 1S East Side 2S Lakeside 1DP Design Point 1 2DP Design Point 2 Routing Diagram for 20058_Exist Prepared by {enter your company name here}, Printed 12/14/2021 HydroCAD® 10.00-26 s/n 11624 © 2020 HydroCAD Software Solutions LLC Subcat Reach Pond Link 20058_Exist Printed 12/14/2021Prepared by {enter your company name here} Page 2HydroCAD® 10.00-26 s/n 11624 © 2020 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (sq-ft) CN Description (subcatchment-numbers) 1,198 98 Existing structures (2S) 1,500 96 Gravel surface, HSG B - Unpaved driveway (1S) 14,115 66 Woods, Poor, HSG B (1S, 2S) 16,813 71 TOTAL AREA Type II 24-hr 25-yr Rainfall=4.18"20058_Exist Printed 12/14/2021Prepared by {enter your company name here} Page 3HydroCAD® 10.00-26 s/n 11624 © 2020 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: East Side Runoff = 0.55 cfs @ 11.90 hrs, Volume=904 cf, Depth= 1.66" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-48.00 hrs, dt= 0.01 hrs Type II 24-hr 25-yr Rainfall=4.18" Area (sf) CN Description 5,044 66 Woods, Poor, HSG B * 1,500 96 Gravel surface, HSG B - Unpaved driveway 6,544 73 Weighted Average 6,544 100.00% Pervious Area Summary for Subcatchment 2S: Lakeside Runoff = 0.76 cfs @ 11.90 hrs, Volume= 1,242 cf, Depth= 1.45" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-48.00 hrs, dt= 0.01 hrs Type II 24-hr 25-yr Rainfall=4.18" Area (sf) CN Description * 1,198 98 Existing structures 9,071 66 Woods, Poor, HSG B 10,269 70 Weighted Average 9,071 88.33% Pervious Area 1,198 11.67% Impervious Area Summary for Pond 1DP: Design Point 1 Inflow Area = 6,544 sf, 0.00% Impervious, Inflow Depth = 1.66" for 25-yr event Inflow = 0.55 cfs @ 11.90 hrs, Volume= 904 cf Primary = 0.55 cfs @ 11.90 hrs, Volume= 904 cf, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind method, Time Span= 5.00-48.00 hrs, dt= 0.01 hrs Summary for Pond 2DP: Design Point 2 Inflow Area = 10,269 sf, 11.67% Impervious, Inflow Depth = 1.45" for 25-yr event Inflow = 0.76 cfs @ 11.90 hrs, Volume= 1,242 cf Primary = 0.76 cfs @ 11.90 hrs, Volume= 1,242 cf, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind method, Time Span= 5.00-48.00 hrs, dt= 0.01 hrs 1S East side 2S Lakeside 3S Motor Court 4S South side 5S Lakefront patio 1DP Design Point 1 1P Permeable Pavers - Motor Court 2DP Design Point 2 2P Permeable Pavers - Patio 3P Infiltration Trench - Driveway 4P Rain Garden - South Side Routing Diagram for 20058_Prop Prepared by {enter your company name here}, Printed 12/14/2021 HydroCAD® 10.00-26 s/n 11624 © 2020 HydroCAD Software Solutions LLC Subcat Reach Pond Link 20058_Prop Printed 12/14/2021Prepared by {enter your company name here} Page 2HydroCAD® 10.00-26 s/n 11624 © 2020 HydroCAD Software Solutions LLC Area Listing (all nodes) Area (sq-ft) CN Description (subcatchment-numbers) 3,462 61 >75% Grass cover, Good, HSG B - Lawn (1S, 2S) 1,698 98 Paved parking, HSG B - Pavers (3S, 5S) 166 98 Paved parking, HSG B - Steps to lake and fire pit area (2S) 1,409 98 Paved roads w/curbs & sewers, HSG B - Driveway and gravel trench (1S) 222 98 Paved roads w/curbs & sewers, HSG B - Gravel Trench (1S) 2,477 98 Unconnected roofs, HSG B (1S, 2S, 3S, 4S, 5S) 4,464 58 Woods/grass comb., Good, HSG B (2S, 4S) 652 58 Woods/grass comb., Good, HSG B - Garden beds (3S, 5S) 2,263 58 Woods/grass comb., Good, HSG B - Garden beds with native trees and shrubs (1S) 16,813 73 TOTAL AREA Type II 24-hr 25-yr Rainfall=4.18"20058_Prop Printed 12/14/2021Prepared by {enter your company name here} Page 3HydroCAD® 10.00-26 s/n 11624 © 2020 HydroCAD Software Solutions LLC Summary for Subcatchment 1S: East side Runoff = 0.45 cfs @ 11.90 hrs, Volume=743 cf, Depth= 1.52" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type II 24-hr 25-yr Rainfall=4.18" Area (sf) CN Description 143 98 Unconnected roofs, HSG B * 1,409 98 Paved roads w/curbs & sewers, HSG B - Driveway and gravel trench * 1,830 61 >75% Grass cover, Good, HSG B - Lawn * 2,263 58 Woods/grass comb., Good, HSG B - Garden beds with native trees and shrubs * 222 98 Paved roads w/curbs & sewers, HSG B - Gravel Trench 5,867 71 Weighted Average 4,093 69.76% Pervious Area 1,774 30.24% Impervious Area 143 8.06% Unconnected Summary for Subcatchment 2S: Lakeside Runoff = 0.29 cfs @ 11.90 hrs, Volume=484 cf, Depth= 0.96" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type II 24-hr 25-yr Rainfall=4.18" Area (sf) CN Adj Description 3,697 58 Woods/grass comb., Good, HSG B * 1,632 61 >75% Grass cover, Good, HSG B - Lawn 549 98 Unconnected roofs, HSG B * 166 98 Paved parking, HSG B - Steps to lake and fire pit area 6,044 64 62 Weighted Average, UI Adjusted 5,329 88.17% Pervious Area 715 11.83% Impervious Area 549 76.78% Unconnected Summary for Subcatchment 3S: Motor Court Runoff = 0.34 cfs @ 11.90 hrs, Volume=594 cf, Depth= 2.90" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type II 24-hr 25-yr Rainfall=4.18" Area (sf) CN Description 884 98 Unconnected roofs, HSG B * 977 98 Paved parking, HSG B - Pavers * 602 58 Woods/grass comb., Good, HSG B - Garden beds 2,463 88 Weighted Average 602 24.44% Pervious Area 1,861 75.56% Impervious Area 884 47.50% Unconnected Type II 24-hr 25-yr Rainfall=4.18"20058_Prop Printed 12/14/2021Prepared by {enter your company name here} Page 4HydroCAD® 10.00-26 s/n 11624 © 2020 HydroCAD Software Solutions LLC Summary for Subcatchment 4S: South side Runoff = 0.05 cfs @ 11.90 hrs, Volume=89 cf, Depth= 1.02" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type II 24-hr 25-yr Rainfall=4.18" Area (sf) CN Adj Description 767 58 Woods/grass comb., Good, HSG B 283 98 Unconnected roofs, HSG B 1,050 69 63 Weighted Average, UI Adjusted 767 73.05% Pervious Area 283 26.95% Impervious Area 283 100.00% Unconnected Summary for Subcatchment 5S: Lakefront patio Runoff = 0.22 cfs @ 11.90 hrs, Volume=443 cf, Depth= 3.83" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type II 24-hr 25-yr Rainfall=4.18" Area (sf) CN Description 618 98 Unconnected roofs, HSG B * 721 98 Paved parking, HSG B - Pavers * 50 58 Woods/grass comb., Good, HSG B - Garden beds 1,389 97 Weighted Average 50 3.60% Pervious Area 1,339 96.40% Impervious Area 618 46.15% Unconnected Summary for Pond 1DP: Design Point 1 Inflow Area = 8,330 sf, 43.64% Impervious, Inflow Depth = 0.77" for 25-yr event Inflow = 0.30 cfs @ 11.90 hrs, Volume= 532 cf Primary = 0.30 cfs @ 11.90 hrs, Volume= 532 cf, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Summary for Pond 1P: Permeable Pavers - Motor Court Inflow Area = 2,463 sf, 75.56% Impervious, Inflow Depth = 2.90" for 25-yr event Inflow = 0.34 cfs @ 11.90 hrs, Volume= 594 cf Outflow = 0.11 cfs @ 11.98 hrs, Volume= 594 cf, Atten= 66%, Lag= 4.7 min Discarded = 0.11 cfs @ 11.98 hrs, Volume= 594 cf Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Type II 24-hr 25-yr Rainfall=4.18"20058_Prop Printed 12/14/2021Prepared by {enter your company name here} Page 5HydroCAD® 10.00-26 s/n 11624 © 2020 HydroCAD Software Solutions LLC Peak Elev= 331.74' @ 11.98 hrs Surf.Area= 977 sf Storage= 99 cf Plug-Flow detention time= 3.3 min calculated for 594 cf (100% of inflow) Center-of-Mass det. time= 3.3 min ( 799.2 - 795.8 ) Volume Invert Avail.Storage Storage Description #1 331.49'395 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Voids Inc.Store Cum.Store Wet.Area (feet)(sq-ft) (feet) (%) (cubic-feet) (cubic-feet)(sq-ft) 331.49 977 166.0 0.0 0 0 977 331.50 977 166.0 40.0 4 4 979 332.50 977 166.0 40.0 391 395 1,145 333.00 977 166.0 0.0 0 395 1,228 Device Routing Invert Outlet Devices #1 Primary 332.83'46.0' long x 0.7' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 Coef. (English) 2.76 2.82 2.93 3.09 3.18 3.22 3.27 3.30 3.32 3.31 3.32 #2 Discarded 331.49'5.050 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 227.00' Discarded OutFlow Max=0.11 cfs @ 11.98 hrs HW=331.74' (Free Discharge) 2=Exfiltration ( Controls 0.11 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=331.49' (Free Discharge) 1=Broad-Crested Rectangular Weir ( Controls 0.00 cfs) Summary for Pond 2DP: Design Point 2 Inflow Area = 8,483 sf, 27.55% Impervious, Inflow Depth = 0.71" for 25-yr event Inflow = 0.29 cfs @ 11.90 hrs, Volume= 499 cf Primary = 0.29 cfs @ 11.90 hrs, Volume= 499 cf, Atten= 0%, Lag= 0.0 min Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs Summary for Pond 2P: Permeable Pavers - Patio Inflow Area = 1,389 sf, 96.40% Impervious, Inflow Depth = 3.83" for 25-yr event Inflow = 0.22 cfs @ 11.90 hrs, Volume= 443 cf Outflow = 0.01 cfs @ 12.11 hrs, Volume= 15 cf, Atten= 93%, Lag= 12.7 min Primary = 0.01 cfs @ 12.11 hrs, Volume= 15 cf Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs / 2 Peak Elev= 332.08' @ 12.11 hrs Surf.Area= 721 sf Storage= 291 cf Plug-Flow detention time= 470.4 min calculated for 15 cf (3% of inflow) Center-of-Mass det. time= (not calculated: outflow precedes inflow) Type II 24-hr 25-yr Rainfall=4.18"20058_Prop Printed 12/14/2021Prepared by {enter your company name here} Page 6HydroCAD® 10.00-26 s/n 11624 © 2020 HydroCAD Software Solutions LLC Volume Invert Avail.Storage Storage Description #1 330.74'291 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Voids Inc.Store Cum.Store Wet.Area (feet)(sq-ft) (feet) (%) (cubic-feet) (cubic-feet)(sq-ft) 330.74 721 123.0 0.0 0 0 721 330.75 721 123.0 40.0 3 3 722 331.75 721 123.0 40.0 288 291 845 332.25 721 123.0 0.0 0 291 907 Device Routing Invert Outlet Devices #1 Primary 332.08'41.0' long x 0.7' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 Coef. (English) 2.76 2.82 2.93 3.09 3.18 3.22 3.27 3.30 3.32 3.31 3.32 Primary OutFlow Max=0.01 cfs @ 12.11 hrs HW=332.08' (Free Discharge) 1=Broad-Crested Rectangular Weir (Weir Controls 0.01 cfs @ 0.13 fps) Summary for Pond 3P: Infiltration Trench - Driveway Inflow Area = 8,330 sf, 43.64% Impervious, Inflow Depth = 1.07" for 25-yr event Inflow = 0.45 cfs @ 11.90 hrs, Volume= 743 cf Outflow = 0.30 cfs @ 11.90 hrs, Volume= 532 cf, Atten= 34%, Lag= 0.0 min Primary = 0.30 cfs @ 11.90 hrs, Volume= 532 cf Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs / 2 Peak Elev= 329.50' @ 11.90 hrs Surf.Area= 222 sf Storage= 178 cf Plug-Flow detention time= 163.2 min calculated for 532 cf (72% of inflow) Center-of-Mass det. time= 55.6 min ( 901.7 - 846.1 ) Volume Invert Avail.Storage Storage Description #1 327.50'178 cf 2.00'W x 111.00'L x 2.00'H Prismatoid 444 cf Overall x 40.0% Voids Device Routing Invert Outlet Devices #1 Primary 329.49'111.0' long x 2.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 Coef. (English) 2.54 2.61 2.61 2.60 2.66 2.70 2.77 2.89 2.88 2.85 3.07 3.20 3.32 Primary OutFlow Max=0.29 cfs @ 11.90 hrs HW=329.50' (Free Discharge) 1=Broad-Crested Rectangular Weir (Weir Controls 0.29 cfs @ 0.26 fps) Type II 24-hr 25-yr Rainfall=4.18"20058_Prop Printed 12/14/2021Prepared by {enter your company name here} Page 7HydroCAD® 10.00-26 s/n 11624 © 2020 HydroCAD Software Solutions LLC Summary for Pond 4P: Rain Garden - South Side Inflow Area = 1,050 sf, 26.95% Impervious, Inflow Depth = 1.02" for 25-yr event Inflow = 0.05 cfs @ 11.90 hrs, Volume= 89 cf Outflow = 0.02 cfs @ 11.98 hrs, Volume= 89 cf, Atten= 65%, Lag= 4.8 min Discarded = 0.02 cfs @ 11.98 hrs, Volume= 89 cf Primary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs / 2 Peak Elev= 328.99' @ 11.98 hrs Surf.Area= 130 sf Storage= 13 cf Plug-Flow detention time= (not calculated: outflow precedes inflow) Center-of-Mass det. time= 2.2 min ( 873.1 - 870.8 ) Volume Invert Avail.Storage Storage Description #1 328.49'235 cf Custom Stage Data (Irregular) Listed below (Recalc) Elevation Surf.Area Perim. Voids Inc.Store Cum.Store Wet.Area (feet)(sq-ft) (feet) (%) (cubic-feet) (cubic-feet)(sq-ft) 328.49 0 0.0 0.0 0 0 0 328.50 130 43.0 20.0 0 0 147 329.00 130 43.0 20.0 13 13 169 330.00 27 21.0 100.0 72 85 285 331.00 130 43.0 100.0 72 157 402 331.50 184 49.0 100.0 78 235 451 Device Routing Invert Outlet Devices #1 Primary 331.00'5.0' long x 3.0' breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 Coef. (English) 2.44 2.58 2.68 2.67 2.65 2.64 2.64 2.68 2.68 2.72 2.81 2.92 2.97 3.07 3.32 #2 Discarded 328.49'5.204 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 326.00' Discarded OutFlow Max=0.02 cfs @ 11.98 hrs HW=328.99' (Free Discharge) 2=Exfiltration ( Controls 0.02 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=328.49' (Free Discharge) 1=Broad-Crested Rectangular Weir ( Controls 0.00 cfs)