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12/18/2017
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Pairing Landscaping and Stormwater Management
Forum
December 12, 2017
Agenda
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Program IntroductionProgram Introduction
Application ProcessApplication Process
Project TypeProject Type
Program TestimonialsProgram Testimonials
Q&AQ&A
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Common Terms
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Stormwater runoffStormwater runoff
Impervious surfaceImpervious surface
1‐inch rainfall1‐inch rainfall
InfiltrationInfiltration
EvapotranspirationEvapotranspiration
Stormwater Quality Cost Share Program
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75% or 90% reimbursement for water quality projects (green stormwater infrastructure) that go above and
beyond stormwater requirements
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Water Quality Project Requirements
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Plants and Soil Media
Water Quality Project Requirements
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www.thomasarmstrong.co.uk
Soil Percolation/Infiltration
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Water Quality Project Requirements
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Water Reuse
City Parks
City Properties
Raleigh ETJ
Streams
Why is Water Quality Important?
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Program Overview
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Educational signageEducational signage
Aspects of the project related to device function or education are
eligible for reimbursement.
Aspects of the project related to device function or education are
eligible for reimbursement.
Design and construction costsDesign and construction costs
Funded annually at $250,000
Funded annually at $250,000
Reimbursement is issued after project is
complete
Reimbursement is issued after project is
complete
Project must exceed regulatory
requirements
Project must exceed regulatory
requirements
What do we fund?
Priority Watersheds – 90% Reimbursement
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Eligibility Requirements
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The property owner pays a stormwater utility fee
The property owner pays a stormwater utility fee
The project is within city limitsThe project is within city limits
The project exceeds required stormwater treatment
The project exceeds required stormwater treatment
The property owner agrees to a 10‐year maintenance term
The property owner agrees to a 10‐year maintenance term
Land‐use deed restriction for projects over $30,000
Land‐use deed restriction for projects over $30,000
Application Process
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Program Application
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Purpose: Explain why the property owner wants to install a project
Purpose: Explain why the property owner wants to install a project
Project details at the planning level: Drainage area, soils information, project design, planting
plan, etc.
Project details at the planning level: Drainage area, soils information, project design, planting
plan, etc.
Budget: Based on estimates from contractors; recommended 10‐20% contingency
Budget: Based on estimates from contractors; recommended 10‐20% contingency
Project Design Guidance
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NC DEQ Stormwater Design Manualhttps://deq.nc.gov/sw‐bmp‐manual
Backyard Rain Garden Manual – NC Cooperative Extensionhttps://forsyth.ces.ncsu.edu/wp‐content/uploads/2016/03/RGmanual2015.pdf?fwd=no
NC Soil and Water Conservation District Community ConservationAssistance Program Design Manualhttp://www.ncagr.gov/SWC/costshareprograms/CCAP/ccapdesignmanual.html
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Rain Gardens/Bioretention Cells
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• Plants and soil filter pollutants from stormwater runoff
• Bowl shape encourages percolation and infiltration
Rain Garden Tips
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Commercial properties:• Meet NC DEQ design standards as closely as possible (maximum side slopes,
internal water storage, bioretention media depths)• Design will most likely vary from drawing below
Residential properties:• Add sand and organic matter to soil if it has a lot of clay• See below for recommended design specifications
All properties:• Meet with Stormwater staff for soil test
3‐6 Inches
Max 3H:1V3 inches
O”‐18”
Not required
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Permeable Pavers
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• Encourages soil percolation and infiltration
• Pea gravel filters pollutants
Vwrrc.vt.edu
Permeable Paver Tips
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All properties:• A soil test by a licensed soil scientist is required to check for expansive clays
and seasonal high water table (reimbursement is provided if the project continues after the soil test)
• Meet NC DEQ design standards as closely as possible• Include a filter strip if pavers are located next to mulched landscaping or
yard runoff that would carry sediment• We prefer that stormwater remains stored in the drainage layer for
infiltration (underdrain should contain upturned elbow)
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Cisterns
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• Water reuse• Encourages soil infiltration• Nitrogen in water decreases fertilizer need
Cistern Tips
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All properties:• Estimate general water usage and try to make sure the water collected will
be used• Include passive drawdown to allow cistern to drain during winter months
when it isn’t used• Unless there is a significant need for water, the size of the cistern should be
no larger than the amount of runoff produced in a 1‐inch storm
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Other Project Options
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www.deeproot.com
Stormwater Wetlands
Green Roofs
Silva Cells
Project Examples – Private Property
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Project Examples – Public Property
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7506 Falls of Neuse Road
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7506 Falls of Neuse Road
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North swale
South swale
Bioretention
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North swale
South swale
Bioretention
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North Swale Summary
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Parameter Value
Length 200 ft
Slope 2%
Estimated Drainage Area 0.96 ac
Estimated Construction Cost $41,000
South Swale Summary
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Parameter Value
Length 150 ft
Slope 2%
Estimated Drainage Area 0.27 ac
Estimated Construction Cost $32,000
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Bioretention Summary
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Parameter Value
Surface Area 2650 ft
Estimated Drainage Area 0.85 ac
Estimated Construction Cost $92,500
Design Details
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Design Details
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Application Details
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Application Details
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Application Details
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Q&A
Lory Willard – City of Raleigh StormwaterPatrick Smith – Soil and Environmental ConsultantsCraig Newton – Saint Andrews Presbyterian Church
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Thank you!
Lory Willard City of Raleigh Stormwater Management Division
Main Phone: 919‐996‐3940Direct Line: 919‐996‐4012
E‐mail: lory.willard@raleighnc.gov
Raleighnc.govSearch: “Stormwater Quality Cost Share Program”
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