HomeMy WebLinkAboutPresentation Slides 08-15-2024August 15, 2024
Conservation Commission
Yarmouth Phase 1 Collection System
Phase 1 Collection System
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Phase 1 Contracts 5 and 6 Pumping Stations
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▪Notice of Intent (NOI) – DEP File No. 083-2442
▪PS1 located at 156 Route 28 (outside of Con Com jurisdiction)
▪PS2 located at 316 Route 28
▪PS3 located by Riverwalk Park
▪Parker River Crossing Double Sewer Siphon using Horizontal
Directional Drill (HDD)
Limited Project per 310 CMR 10.53 (3)(d) – Public utilities
▪Land Subject to Coastal Storm Flowage (LSCSF)(elevation 11 ft)
Locus Map
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PS 2
▪Location is paved and packed gravel
parking lot
▪Submersible wet well and meter vault
accesses via hatches/manholes
▪11.5’ by 17’ building (control room)
▪Small meter vault below ground
▪Standby natural gas generator on 5’ by
12’ concrete pad
▪Raise existing grade to 13 ft to allow FFE
to be 3 ft above BFE of 11 ft
▪Finish graded with 4-inch deep gravel
surface
▪Overall increase of 390 sf of impervious
area
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PS 2 – Site Plan
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PS 2 – Compliance with Mass Stormwater
Standards (New Development)
▪BMPs will provide water quality treatment (90
%TSS), peak attenuation, and recharge to
groundwater:
▪4-inch gravel surface (northern half of the site,
section of driveway, wet well , and generator
pad)
▪Bioretention Area along Rte 28 (southern half
of the site, access drive, and flow meter vault)
▪Coastal – peak attenuation not applicable
▪Overflow from the bioretention area will flow into
the cranberry bogs to the north of the site
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PS 3 – Previously approved under DEP File No.
83-2372
Site Summary:
▪Location is off Riverwalk Access Road
▪Submersible wet well and meter vault
accesses via hatches/manholes
▪40’ by 24’ building (control room)
▪Raise existing grade to allow FFE to be 3
ft above BFE of 11 ft
▪Stormwater runoff captured in gutters
and discharged to Park Developments’
Infiltration System No. 1
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Changes since issuance of OOC:
Reduced impervious area
Site Plan PS 3
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Contracts 5 and 6 Pumping Stations
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▪Climate Resiliency and Adaptation
▪Critical equipment and control building will be 3 feet above effective
100-yr floodplain (el. 11 ft)
▪Mitigation Measures
▪Erosion and sedimentation control (compost logs)
▪Excavation dewatering using basin, sediment
removal
▪Spill control measures
▪Erosion prevention of seeded areas
Double Siphon Parkers River using HDD
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Summary Wetland Resource Area Impacts
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