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<br /> Protecting i rias Areas
<br /> With Vegetated uff r
<br /> By Suzanne S. Rhees,AICP
<br /> Lakes, streams, rivers, and wetlands are not uniform in character;
<br /> they differ in function, water quality, and activities they support.
<br /> However,there is no question that all water • capture sediment and nutrients from adjacent programs that enable,but sometimes also con-
<br /> bodies can benefit from a border of natural lands; strict,local regulations.These state programs,
<br /> vegetation along their shorelines,known as a • capture and remove certain pollutants from including those of Maine,New Hampshire,
<br /> riparian or shoreland buffer.(The term"ripar- runoff,including phosphorus that is at- Washington,Minnesota,and Wisconsin,usual-
<br /> ian"is used here in its broader sense,for land tached to sediment or organic matter and ly set minimum standards,giving local authori-
<br /> abutting any watercourse orwaterbody.) nitrate; ties the ability to be more restrictive—although
<br /> Many states and local jurisdictions • improve stream or ditch bank stability; a few of them set maximum standards that
<br /> require or encourage such buffers along • provide an infiltration area for surface water limit local authority.
<br /> watercourses and waterbodies to improve runoff; Meanwhile,Georgia imposes buffer j
<br /> water quality and provide habitat.This article • provide habitat for pollinators and game requirements as erosion and sedimentation
<br /> explores a selection of state programs;model birds;and controls to protect water quality.Pennsylvania
<br /> codes,and local ordinances in an attempt to shade and cool the stream,protecting applies buffer requirements to a defined set
<br /> identify effective regulatory approaches to pro- against rapid fluctuation in temperature of streams determined to have the highest
<br /> tecting riparian areas with vegetated buffers. that can reduce fish spawning and survival. resource values.While not discussed here,
<br /> The following sections focus primarily on many coastal states require buffers or setbacks
<br /> the more comprehensive statewide programs These multiple benefits make riparian from tidal waters for flood and storm surge
<br /> and the local ordinances that fall within their buffers one of the most cost-effective and protection.In the majority of states,however,
<br /> purview,but also highlight a number of innova- broadly applicable strategies for water quality vegetated buffers are simply a recommended
<br /> tive ordinances that local governments have and habitat improvement.The buffer is essen- best management practice,one which local
<br /> adopted on their own. tially the first line of shoreline defense.While governments may choose to require.
<br /> these benefits will vary depending on topog-
<br /> BENEFITS AND LIMITATIONS raphy,soils,land-use practices,and activities BUFFERS AS PART OF A SHORELAND
<br /> OFVEGETATED BUFFERS occurring upstream of the buffer,in most situ- MANAGEMENT PROGRAM
<br /> A stream,lake,or wetland in a natural wooded ations,the widerthe buffer,the greater the Most state programs are implemented through
<br /> setting may be bordered by riparian forest or benefits.(See the March 2o16 issue of Zoning local zoning ordinances that must meet defined
<br /> steep,wooded bluffs or ravines.In a prairie Practice for a table showing a range of riparian standards and that require state approval,
<br /> setting,a natural buffer may consist of deep- buffer widths for a variety of functions.) although a few states,such as New Hampshire,
<br /> rooted tallgrass prairie plants,a broad expanse Buffers also have their limitations. manage shoreland activities through a central-
<br /> of wet meadows,or other wetland ecosystems. They are ineffective against tile drainage,in ized permit program.In addition to vegetated
<br /> As land is cleared for development or agricul- which subsurface flows are intercepted and buffer requirements,these ordinances typically
<br /> tural uses,streams erode downward,stream- discharged directly into streams and ditches. classify different types of water bodies;enu-
<br /> banks become less stable,runoff increases, Buffers that are too narrow or tack deep-rooted merate land-use districts and use restrictions;
<br /> and flooding becomes more severe.Water vegetation are less effective at capturing runoff establish setbacks,height limits,and bulk
<br /> quality is degraded by sediment and pollut- and pollutants,while intensive clearing of land restrictions for buildings;and include stan-
<br /> ants,such as phosphorus and nitrogen,and outside the buffer can also increase runoff dards for planned unit developments,resorts,
<br /> both aquatic and upland habitat suffer, beyond the buffer's handling capacity. and other specific water-related uses as well
<br /> Buffers in a variety of settings have been as for features of riparian properties,such as
<br /> extensively evaluated for their effectiveness in BUFFERS IN A STATE REGULATORY CONTEXT beaches,stairways,boat landings,and stream-
<br /> improving water quality in lakes,streams,and The place of riparian buffers within a regulatory bank reinforcement.
<br /> wetlands.Among other benefits,buffers can: system varies widely from one state to another. Other state requirements are applied
<br /> Some states,especially those with economies through mandatory erosion and sedimenta-
<br /> reduce flood risk by slowing peak flows and that depend on clean water for recreation and tion controls.The Georgia Erosion and Sedi-
<br /> infiltrating surface runoff; tourism,have created shoreland management mentation Control Act defines a 25-Foot buffer
<br /> ZONINGPRACTICE 9.16
<br /> AMERICAN PLANNING ASSOCIATION JP09e 2
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