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Land Cover or Land Use?  Cover - what is physically on the ground - Forested - Wetlands Cover - what is physically on the ground - Forested - Wetlands Use - what is practiced, permitted or planned - Recreational

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For Example Suggested Language for Local Ordinances 1.  Consider it’s location within the watershed 2.  Minimize disturbance of natural grades and vegetation 3.  Protect natural wetlands and stream buffers.  4.  Maximize infiltration of stormwater 5.  Minimize impervious surfaces.  1.  Consider it’s location within the watershed 2.  Minimize disturbance of natural grades and vegetation 3.  Protect natural wetlands and stream buffers.  4.  Maximize infiltration of stormwater 5.  Minimize impervious surfaces.  The Town of _____ wishes to protect the health of its water resources, and seeks to reduce the impact of development on those resources.  In particular, the commission requires that all new or re-development projects : The Town of _____ wishes to protect the health of its water resources, and seeks to reduce the impact of development on those resources.  In particular, the commission requires that all new or re-development projects :

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Pavement = 24’ R.O.W. = 48’ SubbaseSubbase Shoulder/swale= 12’ Pavement Width can be much less than the right-of-way

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Right-of-Way Widths Paved right-of-ways contribute a significant amount to the imperviousness of a community.  Narrowing roadwaysNarrowing roadways Reducing sidewalk widths or restricting sidewalks to one side of the streetReducing sidewalk widths or restricting sidewalks to one side of the street Requiring ROWs be permeable (grass, dirt, permeable pavement)Requiring ROWs be permeable (grass, dirt, permeable pavement) Reducing the border width between the street and the sidewalkReducing the border width between the street and the sidewalk Installing utilities under street pavementsInstalling utilities under street pavements Placing sidewalks and utilities within easements outside of the ROWPlacing sidewalks and utilities within easements outside of the ROW Redesign the main components of the ROW by:

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Street Lengths and Widths Streets are the greatest source of impervious cover in most subdivisions.  Vary pavement width according to the proposed use LocalLocal 18 to 24 feet CollectorCollector 22 to 30 feet ArterialArterial 24 to 32 feet A hierarchy of road standards

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Parking Reducing the Effects of Imperviousness Require on-site treatment of stormwater using bio- retention medians or other filter typesRequire on-site treatment of stormwater using bio- retention medians or other filter types Require landscaping and buffersRequire landscaping and buffers Regulations should require no more parking than the amount actually needed for specific land uses and encourage pervious areas for the high- demand overload.  Reducing Imperviousness Allow smaller parking spaces for compact carsAllow smaller parking spaces for compact cars Encourage use of alternative pavement typesEncourage use of alternative pavement types Require use of non-black materials for pavementRequire use of non-black materials for pavement

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DrivewaysDriveways Problems … Can contribute 15% to the impervious surface areaCan contribute 15% to the impervious surface area Are hot spots for pollutant accumulationAre hot spots for pollutant accumulation Can be “heat islands”Can be “heat islands”

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Drainage Curb and gutter systems…do not treat stormwater and contribute to floodingCurb and gutter systems…do not treat stormwater and contribute to flooding Vegetated channels remove pollutants on-site and raise times of concentrationVegetated channels remove pollutants on-site and raise times of concentration Bio-retention areas can be used in parking lots to meet landscape requirementsBio-retention areas can be used in parking lots to meet landscape requirements Sand filters use layers of sand to filter pollutantsSand filters use layers of sand to filter pollutants Permeable pavers allow runoff to naturally filter into groundwaterPermeable pavers allow runoff to naturally filter into groundwater On-site drainage systems range from simple grassed swales to more complex bio-retention medians and sand filters…

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è è Want to save money.  è è Want to sell lots.  è è Want to know the rules. ( Clearly Written Regulations can do that) (Reducing impervious surfaces can do that) (Green areas can do that) What About The Developers? 

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In Conclusion….  n Nonpoint source pollution is the #1 water quality problem in the US n There are a variety of pollutants in runoff n Nonpoint source pollution does not pay attention to jurisdictional boundaries n As growth continues, water quality becomes increasingly important

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In Conclusion ….(continued) n Impervious surface coverage is a key indicator of water quality n Through comprehensive planning, innovative site design, and the implementation of BMPs, communities can protect water quality and still grow in a productive way