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MS4_Phase_II_Boundaries (FeatureServer)

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Service Description: This data layer represents MS4 Phase II permitted areas within EPA Region 3. Traditional permits are represented here; non-traditional permits are not.

Service ItemId: 965006181be54c75a8576b4b7897ccfb

Has Versioned Data: false

Max Record Count: 1000

Supported query Formats: JSON

Supports applyEdits with GlobalIds: False

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Description: Summary: This data layer represents MS4 Phase II permitted areas within Region 3. Traditional permits are represented here; non-traditional permits are not. These permitted areas were assigned based on U.S. Census 2000 and U.S. Census 2010 urbanized area coverage for PA, DE, VA, and WV*. Existing MS4 Phase II permitted areas were defined by the 2000 data and expanded MS4 Phase II permit coverage was depicted using the 2010 urbanized area data. (Note that only urbanized areas were utilized in this analysis. Clusters were not included.) Phase II permitted areas (traditional) in MD are represented by the entire municipal boundary rather than urbanized area within the municipal boundary, per the MD state regulations. Exceptions to this are found in Cecil and Washington counties, where these Phase II permits cover the entire county, excluding muncipal areas. *A single exception for WV exists. Berkeley County Phase II permit covers the entire county, excluding incorporated areas. Overview of the EPA MS4 Permit Ptrogram: Polluted stormwater runoff is commonly transported through Municipal Separate Storm Sewer Systems (MS4s), from which it is often discharged untreated into local waterbodies. To prevent harmful pollutants from being washed or dumped into an MS4, operators must obtain a NPDES permit and develop a stormwater management program. Phase I, issued in 1990, requires medium and large cities or certain counties with populations of 100,000 or more to obtain NPDES permit coverage for their stormwater discharges.There are approximately 750 Phase I MS4s. Phase II, issued in 1999, requires regulated small MS4s in urbanized areas, as well as small MS4s outside the urbanized areas that are designated by the permitting authority, to obtain NPDES permit coverage for their stormwater discharges. There are approximately 6,700 Phase II MS4s. Generally, Phase I MS4s are covered by individual permits and Phase II MS4s are covered by a general permit. Each regulated MS4 is required to develop and implement a stormwater management program (SWMP) to reduce the contamination of stormwater runoff and prohibit illicit discharges. WHAT IS AN MS4? An MS4 is a conveyance or system of conveyances that is: - Owned by a state, city, town, village, or other public entity that discharges to waters of the U.S.; - Designed or used to collect or convey stormwater (including storm drains, pipes, ditches, etc.); - Not a combined sewer; and - Not part of a Publicly Owned Treatment Works (sewage treatment plant). Description: MS4 Phase II permitted areas were derived for Region 3 by integrating data from multiple sources. This resulted in an areal data layer that represents the land area that is covered under an MS4 permit, Please note that this should be used as a reference only and should not be relied upon for precise calculations when it comes to permitted area, as combining data sources of different resolutions results in a loss of accuracy.These polygons represent urbanized area that are within the municipality boundaries and incorporated places of Region 3 states. U.S. Census 2000 data was utilized to represent areas within municipalities that should be encompassed in the existing Phase II permit for those municipalities. U.S. Census 2010 data was then utilized to represent expanded areas of Phase II coverage. Features representing MS4 coverage of government agency entitities, such as state Departments of Transportation and federal lands and sites are not currently represented here.Note that these methodolgies apply to the majority of the data but exclude Phase II permits in Maryland and also an exception in West Virginia (mentioned in the Summary above).Steps to deriving these data:1) Municipal boundaries for PA, DE, VA, and WV were integrated. Municipal boundaris for Maryland were embedded into the county boundaries for Maryland (due to MS4 permitting nuances followed by the state of Maryland). This resulted in an administrative layer representing administrative localities that have MS4 obligations to the federal governemt.2) U.S. Census 2000 urban area coverage was modified to represent only land area by removing areas of water, as determined by waterbody data (100K resolution). This resulting urbanized land area was clipped to the administrative layer created in step (1).3) The resulting polygon layer depicts urbanized land area (as of 2000) that is within municipal boundaries of Region 3.4) In progress: MS4 permit administration point data (aka the physial location of the permit, usually a city hall) are now being linked to the polygon area representing MS4 Phase II permitted areas based on spatial location and the permit holder.5) Steps 2 and 3 were repeated using U.S. Census 2010 urban area coverage and appended to the existing MS4 Phase II areas to show additional land area that will soon be (or is currently being) incorporated into existing permits.6) Exceptions:MD Phase II boundaries were not determined by urban area coverage, but rather defined by the municipality boundaries.For Cecil and Washington Counties in MD and Berkeley County in WV, the county boundary (minus muncipal boundaries within the county), was used to represent Phase II coverage for these particular permits.

Copyright Text: U.S. EPA Region 3

Spatial Reference: 4269 (4269)

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Units: esriDecimalDegrees

Child Resources:   Info

Supported Operations:   Query   ConvertFormat   Get Estimates