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adjacent to creeks,streams,rivers,saltwater
<br /> marshes,and most takes and ponds,and a
<br /> 50-foot buffer on trout streams,within which
<br /> land disturbance and vegetation trimming are
<br /> restricted(although some activities are allowed
<br /> under a variance process administered by the .
<br /> state's Department of Natural Resources(§'12-
<br /> 7-6)).
<br /> THRESHOLDS FOR REQUIRING BUFFERS 3
<br /> At a minimum,most of the programs and
<br /> ordinances surveyed here apply to perennial _
<br /> streams,takes,and coastal shorelines.Some T
<br /> programs rely on delineations such as the
<br /> "blue lines"—the perennial streams on U.S.
<br /> Geological Survey maps—or on more detailed
<br /> soil survey maps.Other states and local gov-
<br /> ernments have surveyed and evaluated their
<br /> water resources in order to identify those in
<br /> need of protection.
<br /> Minnesota's shoreland management pro-
<br /> gram establishes different thresholds for in-
<br /> corporated and unincorporated areas.Outside CLASSIFICATION OF WATER BODIES Maine's shoreland program requires es-
<br /> municipal boundaries,shoreland includes all Some statewide regulations and local ordi- tablishment of districts or zones within shore-
<br /> water basins(i.e.,lakes and wetlands)25 acres nances group lakes,streams,and wetlands land areas based on the adjacent water body
<br /> or larger and streams with a drainage area of into classes based on their size,depth,hydro- and other resource characteristics.For exam-
<br /> at least two square mites.Within incorporated logic regimen,location in the landscape,and ple,Resource Protection Districts must include
<br /> areas,the same requirements apply to streams the land uses that surround them.For example, all riverine or tidal loo-year floodplains,lands
<br /> and water basins as small as 10 acres. Minnesota's statewide shoreland program clas- adjacent to high-quality freshwater wetlands,
<br /> In Maine,the shoreland zone applies to sifies three types of lakes,each with different salt marshes and salt meadows,and areas
<br /> lakes(known as great ponds),rivers that drain setback and tot size requirements: with two or more acres of steep slopes(over 20
<br /> at least 25 square mites,and all tidal waters percent).
<br /> and saltwater marshes. Natural Environment Lakes are generally Other land-use districts are defined
<br /> New Hampshire's Shoreland Water Quat- smaller,shallow lakes with a low level of based on their suitability for residential,rec-
<br /> ity Protection Act applies to all tidal waters,all development;many support waterfowl reationat,or commercial development or the
<br /> lakes and ponds larger than io acres,all fourth populations and may have some winter kill presence of intensive water-dependent uses,
<br /> order(medium)and higher streams and rivers, of fish.These are afforded the highest level such as working harbors.
<br /> and other designated rivers. of protection. Many local ordinances classify rivers and
<br /> In Pennsylvania,statewide standards Recreational Development Lakes are deeper streams based on size and significance,with 4
<br /> apply only to streams defined as"exceptional lakes with a moderate level of develop- the most protective standards for perennial r
<br /> value"and"high quality,"determined based ment,defined as between three and 25 streams,For example,Montgomery County,
<br /> on their water quality,biological communities, dwellings per mile of shoreline. Pennsylvania's model ordinance classifies and
<br /> or location on protected lands(§102.14).State • General Development Lakes are large,deep recommends different standards for perennial
<br /> regulations largely prohibit land disturbance lakes with more than 25 dwellings per mile streams(shown as solid lines on soil survey
<br /> within 150 feet of these streams for projects of shoreline;some are bordered by com- maps),intermittent streams,other streams
<br /> requiring a state permit and involving distur- mercial recreation and urban development. with drainage areas of less than 75 acres,and
<br /> bance of more than one acre.However,model wetlands and water bodies.
<br /> ordinances promoted by a number of conserva- Rivers and streams are classified into Although these classifications provide the
<br /> tion organizations and counties in the state six categories,including remote,agricultural, greatest protection for larger streams,research
<br /> call for application of buffers to all perennial forested,transitional,urban,and tributary indicates that smaller headwater streams in
<br /> streams as shown on soil survey maps. streams. the upper reaches of a watershed have the
<br /> Absent state-derived authority,several Each lake and river classification is as- greatest area of land-water interaction and are
<br /> city ordinances,including those of Boulder, signed different lot sizes,tot widths,structure often the most sensitive to sedimentation and
<br /> Colorado,and Salt Lake City,designate specific setbacks,and other dimensional standards. pollution.Where feasible,a narrower buffer
<br /> stream corridors and wetlands,often based on The less developed the setting,the higher the may provide some measure of protection for
<br /> detailed inventories and studies. level of protection. these streams.
<br /> i
<br /> ZONINGPRACTICE 9.16
<br /> AMERICAN PLANNING ASSOCIATION IP09e3
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