site plan review application and stormwater …

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SITE PLAN REVIEW APPLICATION AND STORMWATER REPORT SUBMITTED TO TOWN OF HINGHAM PLANNING BOARD Proposed Residential Redevelopment 40 Harbor View Drive Hingham, Massachusetts APPLICANT: Adam Fleury APF Development Group, LLC. 213 Wompatuck Road Hingham, MA 02043 SUBMITTED TO: Town of Hingham Planning Board 210 Central Street Hingham, MA 02043 PREPARED BY: Cavanaro Consulting, Inc. 687 Main Street Norwell, MA 02061 Revised May 18, 2021

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Page 1: SITE PLAN REVIEW APPLICATION AND STORMWATER …

SITE PLAN REVIEW APPLICATION AND STORMWATER REPORT SUBMITTED TO TOWN OF HINGHAM PLANNING BOARD

Proposed Residential Redevelopment

40 Harbor View Drive Hingham, Massachusetts

APPLICANT: Adam Fleury

APF Development Group, LLC. 213 Wompatuck Road

Hingham, MA 02043

SUBMITTED TO: Town of Hingham

Planning Board 210 Central Street

Hingham, MA 02043

PREPARED BY: Cavanaro Consulting, Inc.

687 Main Street Norwell, MA 02061

Revised May 18, 2021

Page 2: SITE PLAN REVIEW APPLICATION AND STORMWATER …

Table of Contents

Title Section Site Plan Review Narrative and Compliance with I Stormwater Management Standards Construction Period and Long Term Pollution Prevention II and Erosion and Sedimentation Control Illicit Discharge Statement Figures III Figure 1 – MassGIS Oliver Map Figure 2 – FIRM Flood Map Figure 3 – Hingham GIS Drainage Calculations and Supplemental Drainage Information IV Locus Deed V Easement Statement Filing Fee and Peer Review Deposit Site Plan VI

Page 3: SITE PLAN REVIEW APPLICATION AND STORMWATER …

SECTION I

SITE PLAN REVIEW NARRATIVE AND COMPLIANCE WITH

STORMWATER MANAGEMENT STANDARDS

Page 4: SITE PLAN REVIEW APPLICATION AND STORMWATER …

SITE PLAN REVIEW NARRATIVE

The locus property is located at 40 Harbor View Drive and it is approximately 20,899 square feet. The site is not located within any Flood Plain nor are there any wetlands within 100’ of the property. The lot has been developed as a single family residential property with an attached garage and paved driveways serving the dwelling and garage. The dwelling is connected to public water and sewerage. The yards consist primarily of lawn with some areas of landscape. A wooded area borders the side and rear yards. The topography of the lot slopes in a westerly direction toward the two rear property boundaries. NRCS Soil Survey describes the underlying soils as C soils. The project originally consisted of razing the existing dwelling and attached garage and replacing it with a new larger dwelling with attached garage. During the construction of the dwelling additional walls and landscaping were constructed in the rear yard. This additional disturbance of slopes greater than than 10% triggered a Site Plan review per Section IV-B.6.b of the Town of Hingham Zoning Bylaw. Two new subsurface infiltration systems are proposed to be installed in the rear yard to control stormwater runoff. A silt fence will remain installed and maintained during construction.

Compliance with Stormwater Management Standards: The proposed project complies with the Stormwater Management Standards to the maximum extent practicable as follows:

Standard 1: No New Stormwater Conveyances of Untreated Stormwater or Erosion Offsite There will be no new stormwater conveyances of untreated stormwater since a reduction in pavement is being proposed. Post construction potential for erosion will be reduced by reducing peak rate of runoff during the 2 year and 10 year design storm events.

Standard 2: Peak Rate Attenuation Peak rate of runoff will be reduced during the 2 year, 10 year and 100 year design storm events.

Standard 3: Recharge and Discharge Volume Recharge is required follows: Existing Impervious Area = 2,769 ft2 Proposed Impervious Area =4,688 ft2 Increase impervious = 1,919 s.f. (0.25”/12x1,919 SF) = 40 CF The storage capacity of the subsurface infiltration systems is 243 + 243 = 486 CF below the elevation of the outlets. Therefore, the recharge requirement is met.

Standard 4: Water Quality As shown on the accompanying table 80% of the Total Suspended Solids (TSS) has been removed through the use of a crushed stone trench, isolator row in the subsurface infiltration system and an infiltration trench. See attached worksheet.

Page 5: SITE PLAN REVIEW APPLICATION AND STORMWATER …

Existing Pavement Area = 1,157 ft2 Proposed paved area = 1,470 ft2 Total Increase in Impervious Area = 313 ft2 Non-Critical area requires 0.5 inches over new pavement: (0.5”/12”per ft)(313 ft2) = 13 ft3 The water quality volume would be the volume below the outlet pipe on the infiltration filed, which is 243 cubic feet: 13 ft3 required < 243 ft3 proposed, therefore ok.

Standard 5: Land Uses with Higher Pollutant Loads (LUHPPLs) The use of the site as a residential lot does not constitute a higher potential pollutant load use. Thus, Standard 5 does not pertain to this project.

Standard 6: Critical Areas The locus site is not located within a critical area as can be seen on the attached MassGIS Oliver map.

Standard 7: Redevelopment This project is considered redevelopment.

Standard 8: Construction Period Pollution Prevention and Erosion and Sedimentation Control The Operation and Maintenance Plan included with this submittal will ensure proper maintenance of the proposed pollution, erosion and sedimentation measures proposed during construction.

Standard 9: Long Term Operation and Maintenance Plan The Long Term Operation and Maintenance Plan is included within the Operation and Maintenance Plan enclosed in this submittal to ensure the proposed drainage improvements are maintained as intended.

Standard 10: Prohibition of Illicit Discharges Routine visual inspections are scheduled as part of the Operations and Maintenance Plan to prevent illicit discharges into the stormwater system. Furthermore, an Illicit Compliance Statement is included in this submittal.

Improvement Over Existing Conditions The proposed residential redevelopment project is an improvement over existing conditions because it reduces peak rate of runoff during the most frequent 2, 10 and 100-year design storm events.

Page 6: SITE PLAN REVIEW APPLICATION AND STORMWATER …

SECTION II

CONSTRUCTION PERIOD AND LONG TERM POLLUTION PREVENTION AND EROSION AND SEDIMENTATION CONTROL

ILLICIT DISCHARGE STATEMENT

Page 7: SITE PLAN REVIEW APPLICATION AND STORMWATER …

Stormwater Operation and Maintenance Plan and Illicit Discharge Statement

Proposed Residential Redevelopment

40 Harbor View Drive – Hingham, MA 02043 Stormwater Management System’s Owner: APF Development Group, LLC.

System Owner’s Address: 213 Wompatuck Road, Hingham, MA 02043 Party responsible for Operations and Maintenance: Owners of 40 Harbor View Drive

It is most important for a drainage system to be maintained in order for it to work properly. The following is an Operation and Maintenance plan to upkeep the existing non-structural and structural best performance practices as outlined in the Massachusetts Department of Environmental Protection’s Stormwater Management Policy. Operation and Maintenance Plan and Construction Sequencing during Construction: 1) Sediment and Erosion Control Prior to any construction or disturbance, all proposed erosion and sediment control shall be installed. A silt fence shall be installed along the side and rear property boundaries as shown in the Site Plan submitted to the Planning Board. Sedimentation control maintenance:

Silt fences shall be inspected at least once a week and after each rainfall event. Make any required repairs immediately. Repair scoured areas on the back side of fence at this time to prevent future problems.

Should the fabric of the silt fence collapse, tear, decompose or otherwise become

ineffective, replace it within 24 hours of discovery.

Remove silt deposits once they reach 20-30 percent of the height of the silt fence to provide adequate storage volume for the next rain event and to reduce pressure on the silt fence. Care should be taken to avoid undermining the fence during cleanout process.

Silt fences are to be removed upon stabilization of the contributing drainage area.

Accumulated sediment may be spread to form a surface for turf or other vegetation establishment or disposed of elsewhere. The area should be reshaped to permit natural drainage.

2) Infiltration System All infiltration areas shall be excavated and installed after the construction of the foundation systems. No heavy equipment shall traverse the proposed infiltration areas after installation. Per MA DEP Stormwater Guidelines the following work shall be done to stabilize the site prior to installing the subsurface structures:

Page 8: SITE PLAN REVIEW APPLICATION AND STORMWATER …

- Do not allow runoff from any disturbed areas on the site to flow to the subsurface structures. - Rope off the area where the subsurface structures are to be placed. - Accomplish any required excavation with equipment placed just outside the area. If the size of the area intended for exfiltration is too large to accommodate this approach, use trucks with low-pressure tires to minimize compaction. Do not allow any other vehicles within the area to be excavated. - Keep the area above and immediately surrounding the subsurface system roped off to all construction vehicles until the final top surface is installed. - At no time shall the area for the infiltration system be used as a temporary sediment basin. Stockpiles shall be placed away from the subsurface infiltration system and sedimentation fences shall be placed around the perimeter of the infiltration area to prevent the accumulation of sediment within the native soils. 3) Upon completion of construction and permanent stabilization of all disturbed areas the erosion and sediment control may be removed. Operation and Maintenance Plan After Construction: Subsurface Infiltration System: Inspect inspection port at least quarterly and after every major storm event during the first year. Inspections after every major storm event shall take notice of any water standing after 72 hours after the storm ended. After the first year, inspections must be done at least twice yearly. Remove any debris or sediment within reach that may be clogging the system. Roof Drain cleaning: All roof drains shall be cleaned and inspected in late winter or early spring after the snow melts. Inspections should include the gutters, downspouts and all accessible piping. Any visible debris should be removed from inlets and outlets. Snow Management

Any snow and ice buildup on the proposed roof drains will be removed in a timely fashion. Estimated Operation and Maintenance Budget: Maintenance cost will be approximately $200.00 per year.

Page 9: SITE PLAN REVIEW APPLICATION AND STORMWATER …

Illicit Discharges: At no time will the owner or any other individual utilize the stormwater management system for any purpose other than its intended use. The stormwater management system as shown on the attached site plan at no time shall receive discharges other than stormwater, this includes “wastewater discharges and discharges of stormwater contaminated by contact with process wastes, raw materials, raw materials, toxic pollutants, hazardous substances, oil or grease.” __________________________ __________________________ Property Owner (Signature) Property Owner (Print)

Page 10: SITE PLAN REVIEW APPLICATION AND STORMWATER …

SECTION III

FIGURES

Page 11: SITE PLAN REVIEW APPLICATION AND STORMWATER …

National Flood Hazard Layer FIRMette

0 500 1,000 1,500 2,000250Feet

Ü

SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT

SPECIAL FLOODHAZARD AREAS

Without Base Flood Elevation (BFE)Zone A, V, A99

With BFE or DepthZone AE, AO, AH, VE, AR

Regulatory Floodway

0.2% Annual Chance Flood Hazard, Areasof 1% annual chance flood with averagedepth less than one foot or with drainageareas of less than one square mileZone X

Future Conditions 1% AnnualChance Flood HazardZone X

Area with Reduced Flood Risk due toLevee. See Notes.Zone X

Area with Flood Risk due to LeveeZone D

NO SCREENArea of Minimal Flood HazardZone X

Area of Undetermined Flood HazardZone D

Channel, Culvert, or Storm Sewer

Levee, Dike, or Floodwall

Cross Sections with 1% Annual Chance17.5 Water Surface Elevation

Coastal Transect

Coastal Transect BaselineProfile BaselineHydrographic Feature

Base Flood Elevation Line (BFE)

Effective LOMRs

Limit of StudyJurisdiction Boundary

Digital Data Available

No Digital Data Available

Unmapped

This map complies with FEMA's standards for the use ofdigital flood maps if it is not void as described below.The basemap shown complies with FEMA's basemapaccuracy standards

The flood hazard information is derived directly from theauthoritative NFHL web services provided by FEMA. This mapwas exported on 4/7/2021 at 12:32 PM and does notreflect changes or amendments subsequent to this date andtime. The NFHL and effective information may change orbecome superseded by new data over time.

This map image is void if the one or more of the following mapelements do not appear: basemap imagery, flood zone labels,legend, scale bar, map creation date, community identifiers,FIRM panel number, and FIRM effective date. Map images forunmapped and unmodernized areas cannot be used forregulatory purposes.

Legend

OTHER AREAS OFFLOOD HAZARD

OTHER AREAS

GENERALSTRUCTURES

OTHERFEATURES

MAP PANELS

8

B20.2

The pin displayed on the map is an approximatepoint selected by the user and does not representan authoritative property location.

1:6,000

70°55'2"W 42°15'5"N

70°54'24"W 42°14'39"N

Basemap: USGS National Map: Orthoimagery: Data refreshed October, 2020

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USGSFax: 781.659.8186

687 MAIN STREET

Phone: 781.659.8187

P.O. BOX 5175

Cavanaro Consulting

Norwell, Massachusetts 02061

PREPARED FOR:

APF DEVELOPMENT GROUP LLC

40 HARBOR VIEW DRIVE

HINGHAM, MA 02043

LOCUS

AutoCAD SHX Text
DRAWING NO.
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1 OF 1
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SHEET NO.
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FILENAME:
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X:\PROJECTS\
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BPS
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4.1.21
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CCH
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19122
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DATE :
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CHECKED BY :
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DRAWN BY :
AutoCAD SHX Text
PROJECT NO. :
Page 13: SITE PLAN REVIEW APPLICATION AND STORMWATER …
Page 14: SITE PLAN REVIEW APPLICATION AND STORMWATER …

SECTION IV

DRAINAGE CALCULATIONS & SUPPLEMENTAL DRAINAGE INFORMATION

Page 15: SITE PLAN REVIEW APPLICATION AND STORMWATER …

1.0 METHODOLOGY The adequacy of the proposed drainage structures and their ability to function properly were analyzed to minimize detrimental effects due to stormwater conditions. The impacts of storm water are mitigated through several mechanisms such as infiltration, transportation and evaporation. The remaining runoff was quantified through developed and accepted methods.

2.0 OVERVIEW Cavanaro Consulting, Inc. (CC) has analyzed the existing conditions at the site utilizing the HydroCad Storm water modeling program. Storm rainfall, run-off curve numbers, and other site characteristics are input into the program. The results of calculations are output into tables and graphs for each area and control structure.

3.0 DESIGN STORMS CC has computed stormwater run-off calculations for the proposed site, for a 2, 10 and 100 year, 24-hour event. The intensity of these rain events is 3.2”, 4.65” and 6.8” respectively.

4.0 DRAINAGE ANALYSIS The following is the summary of the HydroCAD analysis: To Rear Property Boundaries Storm Existing Post-development

Conditions Conditions 2–Year-24Hour (3.2”) 0.61 cfs 0.044 af 0.50 cfs 0.041 af 10–Year-24Hour (4.65”) 1.26 cfs 0.087 af 1.17 cfs 0.085 af 100–Year-24Hour (6.8”) 2.32 cfs 0.159 af 2.17 cfs 0.159 af

Page 16: SITE PLAN REVIEW APPLICATION AND STORMWATER …

SUPPLEMENTAL INFORMATION

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E1

Exist. Cond. 2019

P1

Proposed Remainder

P2

Roof / Driveway

P3

Portion Roof

1R

Rear Yard2R

Rear Yard

3R

4" PVC

4R

4" PVC

5R

6" PVC-Trench pipe

6R

6" PVC

7R

4" PVC

1P

11 x 42 No. 1

2P

11 x 42 No.2 upper

Routing Diagram for 40 Harbor View 5-2021Prepared by Cavanaro Consulting, Printed 5/17/2021

HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Subcat Reach Pond Link

Page 18: SITE PLAN REVIEW APPLICATION AND STORMWATER …

Type III 24-hr 2 Year Event Rainfall=3.20"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 2HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 pointsRunoff by SCS TR-20 method, UH=SCS, Weighted-CN

Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method

Runoff Area=20,899 sf 13.25% Impervious Runoff Depth=1.09"Subcatchment E1: Exist. Cond. 2019 Tc=5.0 min CN=75 Runoff=0.61 cfs 0.044 af

Runoff Area=17,060 sf 5.18% Impervious Runoff Depth=1.09"Subcatchment P1: Proposed Remainder Tc=5.0 min CN=75 Runoff=0.50 cfs 0.036 af

Runoff Area=2,431 sf 98.60% Impervious Runoff Depth=2.97"Subcatchment P2: Roof / Driveway Tc=5.0 min CN=98 Runoff=0.18 cfs 0.014 af

Runoff Area=1,408 sf 100.00% Impervious Runoff Depth=2.97"Subcatchment P3: Portion Roof Tc=5.0 min CN=98 Runoff=0.10 cfs 0.008 af

Inflow=0.61 cfs 0.044 afReach 1R: Rear Yard Outflow=0.61 cfs 0.044 af

Inflow=0.50 cfs 0.041 afReach 2R: Rear Yard Outflow=0.50 cfs 0.041 af

Avg. Flow Depth=0.00' Max Vel=0.00 fps Inflow=0.00 cfs 0.000 afReach 3R: 4" PVC4.0" Round Pipe n=0.010 L=105.0' S=0.0876 '/' Capacity=0.73 cfs Outflow=0.00 cfs 0.000 af

Avg. Flow Depth=0.15' Max Vel=2.76 fps Inflow=0.10 cfs 0.008 afReach 4R: 4" PVC4.0" Round Pipe n=0.010 L=95.0' S=0.0105 '/' Capacity=0.25 cfs Outflow=0.10 cfs 0.008 af

Avg. Flow Depth=0.16' Max Vel=3.41 fps Inflow=0.18 cfs 0.014 afReach 5R: 6" PVC-Trench pipe6.0" Round Pipe n=0.010 L=75.0' S=0.0133 '/' Capacity=0.84 cfs Outflow=0.18 cfs 0.014 af

Avg. Flow Depth=0.11' Max Vel=7.44 fps Inflow=0.18 cfs 0.014 afReach 6R: 6" PVC4.0" Round Pipe n=0.010 L=15.0' S=0.1067 '/' Capacity=0.81 cfs Outflow=0.18 cfs 0.014 af

Avg. Flow Depth=0.06' Max Vel=5.52 fps Inflow=0.05 cfs 0.005 afReach 7R: 4" PVC4.0" Round Pipe n=0.010 L=12.0' S=0.1250 '/' Capacity=0.87 cfs Outflow=0.05 cfs 0.005 af

Peak Elev=83.65' Storage=290 cf Inflow=0.18 cfs 0.014 afPond 1P: 11 x 42 No. 1 Discarded=0.00 cfs 0.004 af Primary=0.05 cfs 0.005 af Outflow=0.05 cfs 0.009 af

Peak Elev=90.56' Storage=229 cf Inflow=0.10 cfs 0.008 afPond 2P: 11 x 42 No.2 upper Discarded=0.00 cfs 0.004 af Primary=0.00 cfs 0.000 af Outflow=0.00 cfs 0.004 af

Total Runoff Area = 0.960 ac Runoff Volume = 0.101 af Average Runoff Depth = 1.27"82.16% Pervious = 0.788 ac 17.84% Impervious = 0.171 ac

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Type III 24-hr 2 Year Event Rainfall=3.20"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 3HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Summary for Subcatchment E1: Exist. Cond. 2019

Runoff = 0.61 cfs @ 12.08 hrs, Volume= 0.044 af, Depth= 1.09"

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsType III 24-hr 2 Year Event Rainfall=3.20"

Area (sf) CN Description

1,157 98 Paved parking, HSG C1,075 98 Roofs, HSG C

* 537 98 other impervious8,839 74 >75% Grass cover, Good, HSG C9,291 70 Woods, Good, HSG C

20,899 75 Weighted Average18,130 86.75% Pervious Area2,769 13.25% Impervious Area

Tc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)

5.0 Direct Entry, direct

Summary for Subcatchment P1: Proposed Remainder

Runoff = 0.50 cfs @ 12.08 hrs, Volume= 0.036 af, Depth= 1.09"

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsType III 24-hr 2 Year Event Rainfall=3.20"

Area (sf) CN Description

* 130 98 Roofs, HSG C - Porch - Front* 509 98 other impervous

14,352 74 >75% Grass cover, Good, HSG C1,825 70 Woods, Good, HSG C

* 244 98 roof.....

17,060 75 Weighted Average16,177 94.82% Pervious Area

883 5.18% Impervious Area

Tc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)

5.0 Direct Entry, direct

Summary for Subcatchment P2: Roof / Driveway

Runoff = 0.18 cfs @ 12.07 hrs, Volume= 0.014 af, Depth= 2.97"

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsType III 24-hr 2 Year Event Rainfall=3.20"

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Type III 24-hr 2 Year Event Rainfall=3.20"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 4HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Area (sf) CN Description

* 633 98 Roof* 1,470 98 Driveway* 294 98 walks* 34 74 landscape

2,431 98 Weighted Average34 1.40% Pervious Area

2,397 98.60% Impervious Area

Tc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)

5.0 Direct Entry, direct

Summary for Subcatchment P3: Portion Roof

Runoff = 0.10 cfs @ 12.07 hrs, Volume= 0.008 af, Depth= 2.97"

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsType III 24-hr 2 Year Event Rainfall=3.20"

Area (sf) CN Description

* 1,408 98 Roof

1,408 100.00% Impervious Area

Tc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)

5.0 Direct Entry, direct

Summary for Reach 1R: Rear Yard

Inflow Area = 0.480 ac, 13.25% Impervious, Inflow Depth = 1.09" for 2 Year Event eventInflow = 0.61 cfs @ 12.08 hrs, Volume= 0.044 afOutflow = 0.61 cfs @ 12.08 hrs, Volume= 0.044 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs

Summary for Reach 2R: Rear Yard

Inflow Area = 0.480 ac, 22.43% Impervious, Inflow Depth = 1.01" for 2 Year Event eventInflow = 0.50 cfs @ 12.08 hrs, Volume= 0.041 afOutflow = 0.50 cfs @ 12.08 hrs, Volume= 0.041 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs

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Type III 24-hr 2 Year Event Rainfall=3.20"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 5HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Summary for Reach 3R: 4" PVC

Inflow Area = 0.032 ac,100.00% Impervious, Inflow Depth = 0.00" for 2 Year Event eventInflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 afOutflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 0.00 fps, Min. Travel Time= 0.0 minAvg. Velocity = 0.00 fps, Avg. Travel Time= 0.0 min

Peak Storage= 0 cf @ 0.00 hrsAverage Depth at Peak Storage= 0.00'Bank-Full Depth= 0.33' Flow Area= 0.1 sf, Capacity= 0.73 cfs

4.0" Round Pipen= 0.010 PVC, smooth interiorLength= 105.0' Slope= 0.0876 '/'Inlet Invert= 89.70', Outlet Invert= 80.50'

Summary for Reach 4R: 4" PVC

Inflow Area = 0.032 ac,100.00% Impervious, Inflow Depth = 2.97" for 2 Year Event eventInflow = 0.10 cfs @ 12.07 hrs, Volume= 0.008 afOutflow = 0.10 cfs @ 12.09 hrs, Volume= 0.008 af, Atten= 0%, Lag= 1.0 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 2.76 fps, Min. Travel Time= 0.6 minAvg. Velocity = 0.92 fps, Avg. Travel Time= 1.7 min

Peak Storage= 4 cf @ 12.08 hrsAverage Depth at Peak Storage= 0.15'Bank-Full Depth= 0.33' Flow Area= 0.1 sf, Capacity= 0.25 cfs

4.0" Round Pipen= 0.010 PVC, smooth interiorLength= 95.0' Slope= 0.0105 '/'Inlet Invert= 91.00', Outlet Invert= 90.00'

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Type III 24-hr 2 Year Event Rainfall=3.20"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 6HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Summary for Reach 5R: 6" PVC-Trench pipe

Inflow Area = 0.056 ac, 98.60% Impervious, Inflow Depth = 2.97" for 2 Year Event eventInflow = 0.18 cfs @ 12.07 hrs, Volume= 0.014 afOutflow = 0.18 cfs @ 12.08 hrs, Volume= 0.014 af, Atten= 0%, Lag= 0.6 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 3.41 fps, Min. Travel Time= 0.4 minAvg. Velocity = 1.11 fps, Avg. Travel Time= 1.1 min

Peak Storage= 4 cf @ 12.07 hrsAverage Depth at Peak Storage= 0.16'Bank-Full Depth= 0.50' Flow Area= 0.2 sf, Capacity= 0.84 cfs

6.0" Round Pipen= 0.010 PVC, smooth interiorLength= 75.0' Slope= 0.0133 '/'Inlet Invert= 85.50', Outlet Invert= 84.50'

Summary for Reach 6R: 6" PVC

Inflow Area = 0.056 ac, 98.60% Impervious, Inflow Depth = 2.97" for 2 Year Event eventInflow = 0.18 cfs @ 12.08 hrs, Volume= 0.014 afOutflow = 0.18 cfs @ 12.08 hrs, Volume= 0.014 af, Atten= 0%, Lag= 0.1 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 7.44 fps, Min. Travel Time= 0.0 minAvg. Velocity = 2.44 fps, Avg. Travel Time= 0.1 min

Peak Storage= 0 cf @ 12.08 hrsAverage Depth at Peak Storage= 0.11'Bank-Full Depth= 0.33' Flow Area= 0.1 sf, Capacity= 0.81 cfs

4.0" Round Pipen= 0.010 PVC, smooth interiorLength= 15.0' Slope= 0.1067 '/'Inlet Invert= 84.50', Outlet Invert= 82.90'

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Type III 24-hr 2 Year Event Rainfall=3.20"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 7HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Summary for Reach 7R: 4" PVC

Inflow Area = 0.056 ac, 98.60% Impervious, Inflow Depth = 1.04" for 2 Year Event eventInflow = 0.05 cfs @ 12.38 hrs, Volume= 0.005 afOutflow = 0.05 cfs @ 12.38 hrs, Volume= 0.005 af, Atten= 0%, Lag= 0.1 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 5.52 fps, Min. Travel Time= 0.0 minAvg. Velocity = 2.25 fps, Avg. Travel Time= 0.1 min

Peak Storage= 0 cf @ 12.38 hrsAverage Depth at Peak Storage= 0.06'Bank-Full Depth= 0.33' Flow Area= 0.1 sf, Capacity= 0.87 cfs

4.0" Round Pipen= 0.010 PVC, smooth interiorLength= 12.0' Slope= 0.1250 '/'Inlet Invert= 83.00', Outlet Invert= 81.50'

Summary for Pond 1P: 11 x 42 No. 1

Inflow Area = 0.056 ac, 98.60% Impervious, Inflow Depth = 2.97" for 2 Year Event eventInflow = 0.18 cfs @ 12.08 hrs, Volume= 0.014 afOutflow = 0.05 cfs @ 12.38 hrs, Volume= 0.009 af, Atten= 69%, Lag= 17.7 minDiscarded = 0.00 cfs @ 12.38 hrs, Volume= 0.004 afPrimary = 0.05 cfs @ 12.38 hrs, Volume= 0.005 af

Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsPeak Elev= 83.65' @ 12.38 hrs Surf.Area= 462 sf Storage= 290 cf

Plug-Flow detention time= 267.7 min calculated for 0.009 af (67% of inflow)Center-of-Mass det. time= 169.8 min ( 926.6 - 756.7 )

Volume Invert Avail.Storage Storage Description

#1 82.70' 175 cf Custom Stage Data (Irregular) Listed below (Recalc)647 cf Overall - 209 cf Embedded = 437 cf x 40.0% Voids

#2 82.90' 209 cf Cultec C-100 x 15 Inside #1Effective Size= 32.1"W x 12.0"H => 1.86 sf x 7.50'L = 14.0 cfOverall Size= 36.0"W x 12.5"H x 8.00'L with 0.50' Overlap

384 cf Total Available Storage

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Type III 24-hr 2 Year Event Rainfall=3.20"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 8HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area(feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft)

82.70 462 106.0 0 0 46284.10 462 106.0 647 647 610

Device Routing Invert Outlet Devices

#1 Primary 83.50' 4.0" Vert. Orifice/Grate C= 0.600 #2 Discarded 82.70' 0.170 in/hr Exfiltration over Wetted area

Discarded OutFlow Max=0.00 cfs @ 12.38 hrs HW=83.65' (Free Discharge)2=Exfiltration (Exfiltration Controls 0.00 cfs)

Primary OutFlow Max=0.05 cfs @ 12.38 hrs HW=83.65' (Free Discharge)1=Orifice/Grate (Orifice Controls 0.05 cfs @ 1.34 fps)

Summary for Pond 2P: 11 x 42 No.2 upper

Inflow Area = 0.032 ac,100.00% Impervious, Inflow Depth = 2.97" for 2 Year Event eventInflow = 0.10 cfs @ 12.09 hrs, Volume= 0.008 afOutflow = 0.00 cfs @ 17.20 hrs, Volume= 0.004 af, Atten= 98%, Lag= 306.7 minDiscarded = 0.00 cfs @ 17.20 hrs, Volume= 0.004 afPrimary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af

Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsPeak Elev= 90.56' @ 17.20 hrs Surf.Area= 462 sf Storage= 229 cf

Plug-Flow detention time= 428.0 min calculated for 0.004 af (53% of inflow)Center-of-Mass det. time= 307.9 min ( 1,065.1 - 757.2 )

Volume Invert Avail.Storage Storage Description

#1 89.80' 138 cf Custom Stage Data (Irregular) Listed below (Recalc)554 cf Overall - 209 cf Embedded = 345 cf x 40.0% Voids

#2 90.00' 209 cf Cultec C-100 x 15 Inside #1Effective Size= 32.1"W x 12.0"H => 1.86 sf x 7.50'L = 14.0 cfOverall Size= 36.0"W x 12.5"H x 8.00'L with 0.50' Overlap

347 cf Total Available Storage

Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area(feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft)

89.80 462 106.0 0 0 46291.00 462 106.0 554 554 589

Device Routing Invert Outlet Devices

#1 Primary 90.60' 4.0" Vert. Orifice/Grate C= 0.600 #2 Discarded 89.80' 0.170 in/hr Exfiltration over Wetted area

Discarded OutFlow Max=0.00 cfs @ 17.20 hrs HW=90.56' (Free Discharge)2=Exfiltration (Exfiltration Controls 0.00 cfs)

Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=89.80' (Free Discharge)1=Orifice/Grate ( Controls 0.00 cfs)

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Type III 24-hr 10 Year Event Rainfall=4.65"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 9HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 pointsRunoff by SCS TR-20 method, UH=SCS, Weighted-CN

Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method

Runoff Area=20,899 sf 13.25% Impervious Runoff Depth=2.17"Subcatchment E1: Exist. Cond. 2019 Tc=5.0 min CN=75 Runoff=1.26 cfs 0.087 af

Runoff Area=17,060 sf 5.18% Impervious Runoff Depth=2.17"Subcatchment P1: Proposed Remainder Tc=5.0 min CN=75 Runoff=1.03 cfs 0.071 af

Runoff Area=2,431 sf 98.60% Impervious Runoff Depth=4.41"Subcatchment P2: Roof / Driveway Tc=5.0 min CN=98 Runoff=0.26 cfs 0.021 af

Runoff Area=1,408 sf 100.00% Impervious Runoff Depth=4.41"Subcatchment P3: Portion Roof Tc=5.0 min CN=98 Runoff=0.15 cfs 0.012 af

Inflow=1.26 cfs 0.087 afReach 1R: Rear Yard Outflow=1.26 cfs 0.087 af

Inflow=1.17 cfs 0.085 afReach 2R: Rear Yard Outflow=1.17 cfs 0.085 af

Avg. Flow Depth=0.04' Max Vel=3.85 fps Inflow=0.02 cfs 0.003 afReach 3R: 4" PVC4.0" Round Pipe n=0.010 L=105.0' S=0.0876 '/' Capacity=0.73 cfs Outflow=0.02 cfs 0.003 af

Avg. Flow Depth=0.19' Max Vel=3.04 fps Inflow=0.15 cfs 0.012 afReach 4R: 4" PVC4.0" Round Pipe n=0.010 L=95.0' S=0.0105 '/' Capacity=0.25 cfs Outflow=0.15 cfs 0.012 af

Avg. Flow Depth=0.19' Max Vel=3.79 fps Inflow=0.26 cfs 0.021 afReach 5R: 6" PVC-Trench pipe6.0" Round Pipe n=0.010 L=75.0' S=0.0133 '/' Capacity=0.84 cfs Outflow=0.26 cfs 0.021 af

Avg. Flow Depth=0.13' Max Vel=8.27 fps Inflow=0.26 cfs 0.021 afReach 6R: 6" PVC4.0" Round Pipe n=0.010 L=15.0' S=0.1067 '/' Capacity=0.81 cfs Outflow=0.26 cfs 0.021 af

Avg. Flow Depth=0.10' Max Vel=7.90 fps Inflow=0.18 cfs 0.011 afReach 7R: 4" PVC4.0" Round Pipe n=0.010 L=12.0' S=0.1250 '/' Capacity=0.87 cfs Outflow=0.18 cfs 0.011 af

Peak Elev=83.85' Storage=338 cf Inflow=0.26 cfs 0.021 afPond 1P: 11 x 42 No. 1 Discarded=0.00 cfs 0.005 af Primary=0.18 cfs 0.011 af Outflow=0.18 cfs 0.016 af

Peak Elev=90.70' Storage=274 cf Inflow=0.15 cfs 0.012 afPond 2P: 11 x 42 No.2 upper Discarded=0.00 cfs 0.005 af Primary=0.02 cfs 0.003 af Outflow=0.03 cfs 0.007 af

Total Runoff Area = 0.960 ac Runoff Volume = 0.190 af Average Runoff Depth = 2.37"82.16% Pervious = 0.788 ac 17.84% Impervious = 0.171 ac

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Type III 24-hr 10 Year Event Rainfall=4.65"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 10HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Summary for Subcatchment E1: Exist. Cond. 2019

Runoff = 1.26 cfs @ 12.08 hrs, Volume= 0.087 af, Depth= 2.17"

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsType III 24-hr 10 Year Event Rainfall=4.65"

Area (sf) CN Description

1,157 98 Paved parking, HSG C1,075 98 Roofs, HSG C

* 537 98 other impervious8,839 74 >75% Grass cover, Good, HSG C9,291 70 Woods, Good, HSG C

20,899 75 Weighted Average18,130 86.75% Pervious Area2,769 13.25% Impervious Area

Tc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)

5.0 Direct Entry, direct

Summary for Subcatchment P1: Proposed Remainder

Runoff = 1.03 cfs @ 12.08 hrs, Volume= 0.071 af, Depth= 2.17"

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsType III 24-hr 10 Year Event Rainfall=4.65"

Area (sf) CN Description

* 130 98 Roofs, HSG C - Porch - Front* 509 98 other impervous

14,352 74 >75% Grass cover, Good, HSG C1,825 70 Woods, Good, HSG C

* 244 98 roof.....

17,060 75 Weighted Average16,177 94.82% Pervious Area

883 5.18% Impervious Area

Tc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)

5.0 Direct Entry, direct

Summary for Subcatchment P2: Roof / Driveway

Runoff = 0.26 cfs @ 12.07 hrs, Volume= 0.021 af, Depth= 4.41"

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsType III 24-hr 10 Year Event Rainfall=4.65"

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Type III 24-hr 10 Year Event Rainfall=4.65"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 11HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Area (sf) CN Description

* 633 98 Roof* 1,470 98 Driveway* 294 98 walks* 34 74 landscape

2,431 98 Weighted Average34 1.40% Pervious Area

2,397 98.60% Impervious Area

Tc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)

5.0 Direct Entry, direct

Summary for Subcatchment P3: Portion Roof

Runoff = 0.15 cfs @ 12.07 hrs, Volume= 0.012 af, Depth= 4.41"

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsType III 24-hr 10 Year Event Rainfall=4.65"

Area (sf) CN Description

* 1,408 98 Roof

1,408 100.00% Impervious Area

Tc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)

5.0 Direct Entry, direct

Summary for Reach 1R: Rear Yard

Inflow Area = 0.480 ac, 13.25% Impervious, Inflow Depth = 2.17" for 10 Year Event eventInflow = 1.26 cfs @ 12.08 hrs, Volume= 0.087 afOutflow = 1.26 cfs @ 12.08 hrs, Volume= 0.087 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs

Summary for Reach 2R: Rear Yard

Inflow Area = 0.480 ac, 22.43% Impervious, Inflow Depth = 2.12" for 10 Year Event eventInflow = 1.17 cfs @ 12.08 hrs, Volume= 0.085 afOutflow = 1.17 cfs @ 12.08 hrs, Volume= 0.085 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs

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Type III 24-hr 10 Year Event Rainfall=4.65"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 12HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Summary for Reach 3R: 4" PVC

Inflow Area = 0.032 ac,100.00% Impervious, Inflow Depth = 1.10" for 10 Year Event eventInflow = 0.02 cfs @ 12.53 hrs, Volume= 0.003 afOutflow = 0.02 cfs @ 12.55 hrs, Volume= 0.003 af, Atten= 0%, Lag= 0.8 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 3.85 fps, Min. Travel Time= 0.5 minAvg. Velocity = 1.95 fps, Avg. Travel Time= 0.9 min

Peak Storage= 1 cf @ 12.54 hrsAverage Depth at Peak Storage= 0.04'Bank-Full Depth= 0.33' Flow Area= 0.1 sf, Capacity= 0.73 cfs

4.0" Round Pipen= 0.010 PVC, smooth interiorLength= 105.0' Slope= 0.0876 '/'Inlet Invert= 89.70', Outlet Invert= 80.50'

Summary for Reach 4R: 4" PVC

Inflow Area = 0.032 ac,100.00% Impervious, Inflow Depth = 4.41" for 10 Year Event eventInflow = 0.15 cfs @ 12.07 hrs, Volume= 0.012 afOutflow = 0.15 cfs @ 12.09 hrs, Volume= 0.012 af, Atten= 1%, Lag= 0.9 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 3.04 fps, Min. Travel Time= 0.5 minAvg. Velocity = 1.03 fps, Avg. Travel Time= 1.5 min

Peak Storage= 5 cf @ 12.08 hrsAverage Depth at Peak Storage= 0.19'Bank-Full Depth= 0.33' Flow Area= 0.1 sf, Capacity= 0.25 cfs

4.0" Round Pipen= 0.010 PVC, smooth interiorLength= 95.0' Slope= 0.0105 '/'Inlet Invert= 91.00', Outlet Invert= 90.00'

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Type III 24-hr 10 Year Event Rainfall=4.65"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 13HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Summary for Reach 5R: 6" PVC-Trench pipe

Inflow Area = 0.056 ac, 98.60% Impervious, Inflow Depth = 4.41" for 10 Year Event eventInflow = 0.26 cfs @ 12.07 hrs, Volume= 0.021 afOutflow = 0.26 cfs @ 12.08 hrs, Volume= 0.021 af, Atten= 0%, Lag= 0.6 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 3.79 fps, Min. Travel Time= 0.3 minAvg. Velocity = 1.25 fps, Avg. Travel Time= 1.0 min

Peak Storage= 5 cf @ 12.07 hrsAverage Depth at Peak Storage= 0.19'Bank-Full Depth= 0.50' Flow Area= 0.2 sf, Capacity= 0.84 cfs

6.0" Round Pipen= 0.010 PVC, smooth interiorLength= 75.0' Slope= 0.0133 '/'Inlet Invert= 85.50', Outlet Invert= 84.50'

Summary for Reach 6R: 6" PVC

Inflow Area = 0.056 ac, 98.60% Impervious, Inflow Depth = 4.41" for 10 Year Event eventInflow = 0.26 cfs @ 12.08 hrs, Volume= 0.021 afOutflow = 0.26 cfs @ 12.08 hrs, Volume= 0.021 af, Atten= 0%, Lag= 0.1 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 8.27 fps, Min. Travel Time= 0.0 minAvg. Velocity = 2.74 fps, Avg. Travel Time= 0.1 min

Peak Storage= 0 cf @ 12.08 hrsAverage Depth at Peak Storage= 0.13'Bank-Full Depth= 0.33' Flow Area= 0.1 sf, Capacity= 0.81 cfs

4.0" Round Pipen= 0.010 PVC, smooth interiorLength= 15.0' Slope= 0.1067 '/'Inlet Invert= 84.50', Outlet Invert= 82.90'

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Type III 24-hr 10 Year Event Rainfall=4.65"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 14HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Summary for Reach 7R: 4" PVC

Inflow Area = 0.056 ac, 98.60% Impervious, Inflow Depth = 2.41" for 10 Year Event eventInflow = 0.18 cfs @ 12.15 hrs, Volume= 0.011 afOutflow = 0.18 cfs @ 12.16 hrs, Volume= 0.011 af, Atten= 0%, Lag= 0.1 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 7.90 fps, Min. Travel Time= 0.0 minAvg. Velocity = 2.64 fps, Avg. Travel Time= 0.1 min

Peak Storage= 0 cf @ 12.16 hrsAverage Depth at Peak Storage= 0.10'Bank-Full Depth= 0.33' Flow Area= 0.1 sf, Capacity= 0.87 cfs

4.0" Round Pipen= 0.010 PVC, smooth interiorLength= 12.0' Slope= 0.1250 '/'Inlet Invert= 83.00', Outlet Invert= 81.50'

Summary for Pond 1P: 11 x 42 No. 1

Inflow Area = 0.056 ac, 98.60% Impervious, Inflow Depth = 4.41" for 10 Year Event eventInflow = 0.26 cfs @ 12.08 hrs, Volume= 0.021 afOutflow = 0.18 cfs @ 12.15 hrs, Volume= 0.016 af, Atten= 30%, Lag= 4.4 minDiscarded = 0.00 cfs @ 12.15 hrs, Volume= 0.005 afPrimary = 0.18 cfs @ 12.15 hrs, Volume= 0.011 af

Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsPeak Elev= 83.85' @ 12.15 hrs Surf.Area= 462 sf Storage= 338 cf

Plug-Flow detention time= 200.0 min calculated for 0.016 af (77% of inflow)Center-of-Mass det. time= 118.0 min ( 867.4 - 749.4 )

Volume Invert Avail.Storage Storage Description

#1 82.70' 175 cf Custom Stage Data (Irregular) Listed below (Recalc)647 cf Overall - 209 cf Embedded = 437 cf x 40.0% Voids

#2 82.90' 209 cf Cultec C-100 x 15 Inside #1Effective Size= 32.1"W x 12.0"H => 1.86 sf x 7.50'L = 14.0 cfOverall Size= 36.0"W x 12.5"H x 8.00'L with 0.50' Overlap

384 cf Total Available Storage

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Type III 24-hr 10 Year Event Rainfall=4.65"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 15HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area(feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft)

82.70 462 106.0 0 0 46284.10 462 106.0 647 647 610

Device Routing Invert Outlet Devices

#1 Primary 83.50' 4.0" Vert. Orifice/Grate C= 0.600 #2 Discarded 82.70' 0.170 in/hr Exfiltration over Wetted area

Discarded OutFlow Max=0.00 cfs @ 12.15 hrs HW=83.85' (Free Discharge)2=Exfiltration (Exfiltration Controls 0.00 cfs)

Primary OutFlow Max=0.18 cfs @ 12.15 hrs HW=83.85' (Free Discharge)1=Orifice/Grate (Orifice Controls 0.18 cfs @ 2.07 fps)

Summary for Pond 2P: 11 x 42 No.2 upper

Inflow Area = 0.032 ac,100.00% Impervious, Inflow Depth = 4.41" for 10 Year Event eventInflow = 0.15 cfs @ 12.09 hrs, Volume= 0.012 afOutflow = 0.03 cfs @ 12.53 hrs, Volume= 0.007 af, Atten= 83%, Lag= 27.0 minDiscarded = 0.00 cfs @ 12.53 hrs, Volume= 0.005 afPrimary = 0.02 cfs @ 12.53 hrs, Volume= 0.003 af

Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsPeak Elev= 90.70' @ 12.53 hrs Surf.Area= 462 sf Storage= 274 cf

Plug-Flow detention time= 307.2 min calculated for 0.007 af (63% of inflow)Center-of-Mass det. time= 201.4 min ( 951.3 - 749.9 )

Volume Invert Avail.Storage Storage Description

#1 89.80' 138 cf Custom Stage Data (Irregular) Listed below (Recalc)554 cf Overall - 209 cf Embedded = 345 cf x 40.0% Voids

#2 90.00' 209 cf Cultec C-100 x 15 Inside #1Effective Size= 32.1"W x 12.0"H => 1.86 sf x 7.50'L = 14.0 cfOverall Size= 36.0"W x 12.5"H x 8.00'L with 0.50' Overlap

347 cf Total Available Storage

Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area(feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft)

89.80 462 106.0 0 0 46291.00 462 106.0 554 554 589

Device Routing Invert Outlet Devices

#1 Primary 90.60' 4.0" Vert. Orifice/Grate C= 0.600 #2 Discarded 89.80' 0.170 in/hr Exfiltration over Wetted area

Discarded OutFlow Max=0.00 cfs @ 12.53 hrs HW=90.70' (Free Discharge)2=Exfiltration (Exfiltration Controls 0.00 cfs)

Primary OutFlow Max=0.02 cfs @ 12.53 hrs HW=90.70' (Free Discharge)1=Orifice/Grate (Orifice Controls 0.02 cfs @ 1.08 fps)

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Type III 24-hr 100 Year Event Rainfall=6.80"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 16HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Time span=0.00-30.00 hrs, dt=0.01 hrs, 3001 pointsRunoff by SCS TR-20 method, UH=SCS, Weighted-CN

Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method

Runoff Area=20,899 sf 13.25% Impervious Runoff Depth=3.97"Subcatchment E1: Exist. Cond. 2019 Tc=5.0 min CN=75 Runoff=2.32 cfs 0.159 af

Runoff Area=17,060 sf 5.18% Impervious Runoff Depth=3.97"Subcatchment P1: Proposed Remainder Tc=5.0 min CN=75 Runoff=1.89 cfs 0.130 af

Runoff Area=2,431 sf 98.60% Impervious Runoff Depth=6.56"Subcatchment P2: Roof / Driveway Tc=5.0 min CN=98 Runoff=0.39 cfs 0.031 af

Runoff Area=1,408 sf 100.00% Impervious Runoff Depth=6.56"Subcatchment P3: Portion Roof Tc=5.0 min CN=98 Runoff=0.22 cfs 0.018 af

Inflow=2.32 cfs 0.159 afReach 1R: Rear Yard Outflow=2.32 cfs 0.159 af

Inflow=2.17 cfs 0.159 afReach 2R: Rear Yard Outflow=2.17 cfs 0.159 af

Avg. Flow Depth=0.09' Max Vel=6.32 fps Inflow=0.13 cfs 0.008 afReach 3R: 4" PVC4.0" Round Pipe n=0.010 L=105.0' S=0.0876 '/' Capacity=0.73 cfs Outflow=0.13 cfs 0.008 af

Avg. Flow Depth=0.24' Max Vel=3.28 fps Inflow=0.22 cfs 0.018 afReach 4R: 4" PVC4.0" Round Pipe n=0.010 L=95.0' S=0.0105 '/' Capacity=0.25 cfs Outflow=0.22 cfs 0.018 af

Avg. Flow Depth=0.24' Max Vel=4.19 fps Inflow=0.39 cfs 0.031 afReach 5R: 6" PVC-Trench pipe6.0" Round Pipe n=0.010 L=75.0' S=0.0133 '/' Capacity=0.84 cfs Outflow=0.38 cfs 0.031 af

Avg. Flow Depth=0.16' Max Vel=9.14 fps Inflow=0.38 cfs 0.031 afReach 6R: 6" PVC4.0" Round Pipe n=0.010 L=15.0' S=0.1067 '/' Capacity=0.81 cfs Outflow=0.38 cfs 0.031 af

Avg. Flow Depth=0.13' Max Vel=8.88 fps Inflow=0.28 cfs 0.021 afReach 7R: 4" PVC4.0" Round Pipe n=0.010 L=12.0' S=0.1250 '/' Capacity=0.87 cfs Outflow=0.28 cfs 0.021 af

Peak Elev=84.10' Storage=384 cf Inflow=0.38 cfs 0.031 afPond 1P: 11 x 42 No. 1 Discarded=0.00 cfs 0.005 af Primary=0.28 cfs 0.021 af Outflow=0.28 cfs 0.026 af

Peak Elev=90.86' Storage=318 cf Inflow=0.22 cfs 0.018 afPond 2P: 11 x 42 No.2 upper Discarded=0.00 cfs 0.005 af Primary=0.13 cfs 0.008 af Outflow=0.13 cfs 0.013 af

Total Runoff Area = 0.960 ac Runoff Volume = 0.337 af Average Runoff Depth = 4.21"82.16% Pervious = 0.788 ac 17.84% Impervious = 0.171 ac

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Type III 24-hr 100 Year Event Rainfall=6.80"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 17HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Summary for Subcatchment E1: Exist. Cond. 2019

Runoff = 2.32 cfs @ 12.07 hrs, Volume= 0.159 af, Depth= 3.97"

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsType III 24-hr 100 Year Event Rainfall=6.80"

Area (sf) CN Description

1,157 98 Paved parking, HSG C1,075 98 Roofs, HSG C

* 537 98 other impervious8,839 74 >75% Grass cover, Good, HSG C9,291 70 Woods, Good, HSG C

20,899 75 Weighted Average18,130 86.75% Pervious Area2,769 13.25% Impervious Area

Tc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)

5.0 Direct Entry, direct

Summary for Subcatchment P1: Proposed Remainder

Runoff = 1.89 cfs @ 12.07 hrs, Volume= 0.130 af, Depth= 3.97"

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsType III 24-hr 100 Year Event Rainfall=6.80"

Area (sf) CN Description

* 130 98 Roofs, HSG C - Porch - Front* 509 98 other impervous

14,352 74 >75% Grass cover, Good, HSG C1,825 70 Woods, Good, HSG C

* 244 98 roof.....

17,060 75 Weighted Average16,177 94.82% Pervious Area

883 5.18% Impervious Area

Tc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)

5.0 Direct Entry, direct

Summary for Subcatchment P2: Roof / Driveway

Runoff = 0.39 cfs @ 12.07 hrs, Volume= 0.031 af, Depth= 6.56"

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsType III 24-hr 100 Year Event Rainfall=6.80"

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Type III 24-hr 100 Year Event Rainfall=6.80"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 18HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Area (sf) CN Description

* 633 98 Roof* 1,470 98 Driveway* 294 98 walks* 34 74 landscape

2,431 98 Weighted Average34 1.40% Pervious Area

2,397 98.60% Impervious Area

Tc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)

5.0 Direct Entry, direct

Summary for Subcatchment P3: Portion Roof

Runoff = 0.22 cfs @ 12.07 hrs, Volume= 0.018 af, Depth= 6.56"

Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsType III 24-hr 100 Year Event Rainfall=6.80"

Area (sf) CN Description

* 1,408 98 Roof

1,408 100.00% Impervious Area

Tc Length Slope Velocity Capacity Description(min) (feet) (ft/ft) (ft/sec) (cfs)

5.0 Direct Entry, direct

Summary for Reach 1R: Rear Yard

Inflow Area = 0.480 ac, 13.25% Impervious, Inflow Depth = 3.97" for 100 Year Event eventInflow = 2.32 cfs @ 12.07 hrs, Volume= 0.159 afOutflow = 2.32 cfs @ 12.07 hrs, Volume= 0.159 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs

Summary for Reach 2R: Rear Yard

Inflow Area = 0.480 ac, 22.43% Impervious, Inflow Depth = 3.98" for 100 Year Event eventInflow = 2.17 cfs @ 12.08 hrs, Volume= 0.159 afOutflow = 2.17 cfs @ 12.08 hrs, Volume= 0.159 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrs

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Type III 24-hr 100 Year Event Rainfall=6.80"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 19HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Summary for Reach 3R: 4" PVC

Inflow Area = 0.032 ac,100.00% Impervious, Inflow Depth = 3.10" for 100 Year Event eventInflow = 0.13 cfs @ 12.18 hrs, Volume= 0.008 afOutflow = 0.13 cfs @ 12.19 hrs, Volume= 0.008 af, Atten= 0%, Lag= 0.5 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 6.32 fps, Min. Travel Time= 0.3 minAvg. Velocity = 2.14 fps, Avg. Travel Time= 0.8 min

Peak Storage= 2 cf @ 12.19 hrsAverage Depth at Peak Storage= 0.09'Bank-Full Depth= 0.33' Flow Area= 0.1 sf, Capacity= 0.73 cfs

4.0" Round Pipen= 0.010 PVC, smooth interiorLength= 105.0' Slope= 0.0876 '/'Inlet Invert= 89.70', Outlet Invert= 80.50'

Summary for Reach 4R: 4" PVC

Inflow Area = 0.032 ac,100.00% Impervious, Inflow Depth = 6.56" for 100 Year Event eventInflow = 0.22 cfs @ 12.07 hrs, Volume= 0.018 afOutflow = 0.22 cfs @ 12.08 hrs, Volume= 0.018 af, Atten= 1%, Lag= 0.9 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 3.28 fps, Min. Travel Time= 0.5 minAvg. Velocity = 1.16 fps, Avg. Travel Time= 1.4 min

Peak Storage= 6 cf @ 12.08 hrsAverage Depth at Peak Storage= 0.24'Bank-Full Depth= 0.33' Flow Area= 0.1 sf, Capacity= 0.25 cfs

4.0" Round Pipen= 0.010 PVC, smooth interiorLength= 95.0' Slope= 0.0105 '/'Inlet Invert= 91.00', Outlet Invert= 90.00'

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Type III 24-hr 100 Year Event Rainfall=6.80"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 20HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Summary for Reach 5R: 6" PVC-Trench pipe

Inflow Area = 0.056 ac, 98.60% Impervious, Inflow Depth = 6.56" for 100 Year Event eventInflow = 0.39 cfs @ 12.07 hrs, Volume= 0.031 afOutflow = 0.38 cfs @ 12.08 hrs, Volume= 0.031 af, Atten= 0%, Lag= 0.5 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 4.19 fps, Min. Travel Time= 0.3 minAvg. Velocity = 1.41 fps, Avg. Travel Time= 0.9 min

Peak Storage= 7 cf @ 12.07 hrsAverage Depth at Peak Storage= 0.24'Bank-Full Depth= 0.50' Flow Area= 0.2 sf, Capacity= 0.84 cfs

6.0" Round Pipen= 0.010 PVC, smooth interiorLength= 75.0' Slope= 0.0133 '/'Inlet Invert= 85.50', Outlet Invert= 84.50'

Summary for Reach 6R: 6" PVC

Inflow Area = 0.056 ac, 98.60% Impervious, Inflow Depth = 6.56" for 100 Year Event eventInflow = 0.38 cfs @ 12.08 hrs, Volume= 0.031 afOutflow = 0.38 cfs @ 12.08 hrs, Volume= 0.031 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 9.14 fps, Min. Travel Time= 0.0 minAvg. Velocity = 3.08 fps, Avg. Travel Time= 0.1 min

Peak Storage= 1 cf @ 12.08 hrsAverage Depth at Peak Storage= 0.16'Bank-Full Depth= 0.33' Flow Area= 0.1 sf, Capacity= 0.81 cfs

4.0" Round Pipen= 0.010 PVC, smooth interiorLength= 15.0' Slope= 0.1067 '/'Inlet Invert= 84.50', Outlet Invert= 82.90'

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Type III 24-hr 100 Year Event Rainfall=6.80"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 21HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Summary for Reach 7R: 4" PVC

Inflow Area = 0.056 ac, 98.60% Impervious, Inflow Depth = 4.50" for 100 Year Event eventInflow = 0.28 cfs @ 12.15 hrs, Volume= 0.021 afOutflow = 0.28 cfs @ 12.15 hrs, Volume= 0.021 af, Atten= 0%, Lag= 0.0 min

Routing by Stor-Ind+Trans method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsMax. Velocity= 8.88 fps, Min. Travel Time= 0.0 minAvg. Velocity = 3.17 fps, Avg. Travel Time= 0.1 min

Peak Storage= 0 cf @ 12.15 hrsAverage Depth at Peak Storage= 0.13'Bank-Full Depth= 0.33' Flow Area= 0.1 sf, Capacity= 0.87 cfs

4.0" Round Pipen= 0.010 PVC, smooth interiorLength= 12.0' Slope= 0.1250 '/'Inlet Invert= 83.00', Outlet Invert= 81.50'

Summary for Pond 1P: 11 x 42 No. 1

Inflow Area = 0.056 ac, 98.60% Impervious, Inflow Depth = 6.56" for 100 Year Event eventInflow = 0.38 cfs @ 12.08 hrs, Volume= 0.031 afOutflow = 0.28 cfs @ 12.15 hrs, Volume= 0.026 af, Atten= 28%, Lag= 4.2 minDiscarded = 0.00 cfs @ 12.15 hrs, Volume= 0.005 afPrimary = 0.28 cfs @ 12.15 hrs, Volume= 0.021 af

Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsPeak Elev= 84.10' @ 12.15 hrs Surf.Area= 462 sf Storage= 384 cf

Plug-Flow detention time= 160.1 min calculated for 0.026 af (85% of inflow)Center-of-Mass det. time= 93.6 min ( 837.0 - 743.4 )

Volume Invert Avail.Storage Storage Description

#1 82.70' 175 cf Custom Stage Data (Irregular) Listed below (Recalc)647 cf Overall - 209 cf Embedded = 437 cf x 40.0% Voids

#2 82.90' 209 cf Cultec C-100 x 15 Inside #1Effective Size= 32.1"W x 12.0"H => 1.86 sf x 7.50'L = 14.0 cfOverall Size= 36.0"W x 12.5"H x 8.00'L with 0.50' Overlap

384 cf Total Available Storage

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Type III 24-hr 100 Year Event Rainfall=6.80"40 Harbor View 5-2021 Printed 5/17/2021Prepared by Cavanaro Consulting

Page 22HydroCAD® 10.00-24 s/n 01769 © 2018 HydroCAD Software Solutions LLC

Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area(feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft)

82.70 462 106.0 0 0 46284.10 462 106.0 647 647 610

Device Routing Invert Outlet Devices

#1 Primary 83.50' 4.0" Vert. Orifice/Grate C= 0.600 #2 Discarded 82.70' 0.170 in/hr Exfiltration over Wetted area

Discarded OutFlow Max=0.00 cfs @ 12.15 hrs HW=84.10' (Free Discharge)2=Exfiltration (Exfiltration Controls 0.00 cfs)

Primary OutFlow Max=0.28 cfs @ 12.15 hrs HW=84.10' (Free Discharge)1=Orifice/Grate (Orifice Controls 0.28 cfs @ 3.16 fps)

Summary for Pond 2P: 11 x 42 No.2 upper

Inflow Area = 0.032 ac,100.00% Impervious, Inflow Depth = 6.56" for 100 Year Event eventInflow = 0.22 cfs @ 12.08 hrs, Volume= 0.018 afOutflow = 0.13 cfs @ 12.18 hrs, Volume= 0.013 af, Atten= 41%, Lag= 5.8 minDiscarded = 0.00 cfs @ 12.18 hrs, Volume= 0.005 afPrimary = 0.13 cfs @ 12.18 hrs, Volume= 0.008 af

Routing by Stor-Ind method, Time Span= 0.00-30.00 hrs, dt= 0.01 hrsPeak Elev= 90.86' @ 12.18 hrs Surf.Area= 462 sf Storage= 318 cf

Plug-Flow detention time= 222.9 min calculated for 0.013 af (74% of inflow)Center-of-Mass det. time= 133.4 min ( 877.3 - 743.9 )

Volume Invert Avail.Storage Storage Description

#1 89.80' 138 cf Custom Stage Data (Irregular) Listed below (Recalc)554 cf Overall - 209 cf Embedded = 345 cf x 40.0% Voids

#2 90.00' 209 cf Cultec C-100 x 15 Inside #1Effective Size= 32.1"W x 12.0"H => 1.86 sf x 7.50'L = 14.0 cfOverall Size= 36.0"W x 12.5"H x 8.00'L with 0.50' Overlap

347 cf Total Available Storage

Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area(feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft)

89.80 462 106.0 0 0 46291.00 462 106.0 554 554 589

Device Routing Invert Outlet Devices

#1 Primary 90.60' 4.0" Vert. Orifice/Grate C= 0.600 #2 Discarded 89.80' 0.170 in/hr Exfiltration over Wetted area

Discarded OutFlow Max=0.00 cfs @ 12.18 hrs HW=90.86' (Free Discharge)2=Exfiltration (Exfiltration Controls 0.00 cfs)

Primary OutFlow Max=0.13 cfs @ 12.18 hrs HW=90.86' (Free Discharge)1=Orifice/Grate (Orifice Controls 0.13 cfs @ 1.75 fps)

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PSUBFax: 781.659.8186

687 MAIN STREET

Phone: 781.659.8187

P.O. BOX 5175

Cavanaro Consulting

Norwell, Massachusetts 02061

PREPARED FOR:

APF DEVELOPMENT GROUP LLC

40 HARBOR VIEW DRIVE

HINGHAM, MA 02043

AutoCAD SHX Text
DRIVEWAY = 1,470 = 1,470 DWELLING 633+244+1,408 = 2,285 = 2,285 PORCH = 130 = 130 OTHER IMPERVIOUS 294+318+191 = 803 = 803 LAWN 7,767+6,550+34 = 14,351 = 14,351 WOODS 1,860 = 1,860 = 1,860 TOTAL= 20,899TOTAL= 20,899
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1,408 S.F. HOUSE
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633 S.F. HOUSE
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318 S.F. PATIO
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6,550 S.F. LAWN
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191 S.F. STONE WALL/STEPS
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7,767 S.F. LAWN
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294 S.F. WALK/WALLS
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130 S.F. PORCH
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1,860 S.F. WOODS
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34 S.F. LANDSCAPE
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1470 S.F. DRIVEWAY
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244 S.F. HOUSE
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DATE :
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ESUB

Fax: 781.659.8186

687 MAIN STREET

Phone: 781.659.8187

P.O. BOX 5175

Cavanaro Consulting

Norwell, Massachusetts 02061

PREPARED FOR:

APF DEVELOPMENT GROUP LLC

40 HARBOR VIEW DRIVE

HINGHAM, MA 02043

AutoCAD SHX Text
BIT. CONC. DRIVE
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OVERGROWN VEGETATION
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OVERGROWN VEGETATION
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PVMNT =1,157 =1,157 DWELLING =1,075 =1,075 OTHER IMPV. 200+209 +111+17 =537 =537 LAWN =8,839 =8,839 WOODS 9163 + 132 =9,291 =9,291 TOTAL= 20,899
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9,159 S.F. WOODS
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111 S.F. SHED
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8,839 S.F. LAWN
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209 S.F. PATIO
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1,075 S.F. HOUSE
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1,157 S.F. DRIVEWAY
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200 S.F. CONC. WALK
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132 S.F. LANDSC.
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REVISED 5/17/21
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SECTION V

LOCUS DEED EASEMENT STATEMENT

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Easement Statement There are no known recorded existing or proposed stormwater easements in the area of proposed work.

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SECTION VI

SITE PLAN See Attached