City of Attleboro Massachusetts Comprehensive Code Revision to Implement LID Managing Wet Weather in the Blackstone River Watershed Thursday, May 14, 2009 Whitinsville, MA
What is Comprehensive Code Revision? Updated Stormwater Management Ordinance: Requires LID evaluation; Addresses NPDES permit requirements; Identical Regulations for Conservation, Planning Board, ZBA; Updated DPW Construction Standards; Earth removal regulations related to clearing and grading;
What is Comprehensive Code Revision? Updated Landscape Ordinance; Updated Floodplain and Earth Removal District; Water Resource Protection District; Revised Open Space Residential Design (OSRD) Ordinance; By-right; Incorporates Green Design Principles; Modest mixed use component. New Site Plan Review Ordinance.
Low Impact Development (LID) Parking swale Grass swale Parking lot bioretention West Farms Mall, W. Hartford, CT Grass overflow parking
Performance Criteria: Post Construction Controls A. Comply with DEP Standards and Reference DEP 2008 Stormwater Standards B. General Criteria 1. No Untreated Discharges to Resources 2. Site Design Criteria 3. Recharge (based on DEP) 4. Water Quality Volume (DEP criteria or >) 5. Channel Protection Volume (e.g. 1-Year ED) 6. Overbank Flooding (10-Year Storm) 7. Extreme Flooding (100-Year Storm)
Site Design Criteria: A. Use LID measures to the Max Extent Practicable B. Document Planning Process 1. Identify and map critical resources 2. Delineate potential building envelopes that avoid these resource areas C. Document % Natural Open Space Retained D. Minimize Impervious Surfaces and Document % of Site Imperviousness E. Disconnect Impervious Surfaces and Document % of Effective Impervious Cover F. Document Use of Applicable Site Design Features
Rain Gardens/Bioretention
EARTH REMOVAL ORDINANCE GOALS Regulate Changes in Topography Groundwater Protection Protection of Abutters Regulate High Impact Uses (Mining or Large-Scale Clearing and Grading) OSRD exempt from ER Special Permit No pre-permit clearing!
Landscape Ordinance Traditional components, such as street trees, non-invasive species, planting specifications; Low maintenance/native vegetation to limit irrigation requirements; Retention of natural vegetation requirements; Limiting turf grass areas?
Standard OSRD Permit By Right with Site Plan Review requirements Features Highly inclusive eligibility Strong four-step design process Clear requirements for open space
Affordable Housing OSRD Permit Special Permit for Density Bonus Features Potential 50% increase in Base Yield Two additional market rate for every affordable unit
GREEN DESIGN OSRD New Definitions Glazing - the transparent part of a wall. Solar Reflectance Index (SRI) Purpose and Intent Healthy, energy efficient residential neighborhoods Compact, walkable, and economically viable Integrate attractive residential, commercial, open space, and environmentally-friendly amenities
GREEN DESIGN OSRD Allowable Uses Residential Retail, Service and Commercial - selling principally convenience goods; Repair and Service Businesses serving local needs. Site Yield Approved Yield Plan Non-residential space limited to 500 ft 2 residential per unit, but < 5,000 ft 2 Density bonus of 50%, provided design stds are followed.
GREEN DESIGN OSRD Residential Design Standards Natural landscape preserved; Open space designed as a visual amenity; Pedestrian access to proposed commercial development; Building orientation to maximize solar capture; Building roofs standards to allow for installation of solar power; Building glazing requirements for north- and southfacing walls; 10% on-site renewable energy requirements; Solar reflective limitations on paving and buildings;
Contact Us Rich Claytor, Principal Engineer Nate Kelly, Principal Planner rclaytor@horsleywitten.com nkelly@horsleywitten.com, Inc. Sandwich, MA 508-833-6600 Providence, RI 401-272-1717 www.horsleywitten.com