Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN><SPAN>This feature class contains WSDOT’s stormwater artificial discharge points. </SPAN></SPAN><SPAN><SPAN>An artificial discharge point is used to represent the estimated discharge point for systems ending in a polygon feature type (roadside slope polygon, dispersion area, infiltration pond, evaporation pond, etc.) where there is no discrete point of discharge.</SPAN></SPAN><SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></SPAN></P></DIV></DIV></DIV>
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN><SPAN>This feature class contains WSDOT’s stormwater artificial paths. An artificial path is </SPAN></SPAN><SPAN><SPAN>used to represent flow through a dispersion area, roadside slope polygon, or stormwater pond polygon when there is no other conveyance feature from the inlet to outlet structure. It is also used for areas where stormwater flow is briefly dispersed to sheet flow from the end of a conveyance and then concentrated again by another downstream conveyance prior to discharge. These paths are important for maintaining connectivity of the stormwater system GIS model. </SPAN></SPAN><SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></SPAN></P></DIV></DIV></DIV>
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>This feature class contains WSDOT’s stormwater cabinets.</SPAN></SPAN><SPAN><SPAN>A stormwater cabinet is an enclosure of various material types and dimensions that houses WSDOT stormwater monitoring equipment.</SPAN></SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></P></DIV></DIV></DIV>
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>This feature class contains WSDOT’s stormwater concrete barriers.</SPAN></SPAN><SPAN><SPAN>Stormwater concrete barriers are barriers or walls, such as single-slope or K-barriers, which concentrate and convey stormwater flows, even if they were not designed or installed with the primary intent of being a conveyance. This feature class only contains concrete barrier segments actively concentrating and conveying stormwater flows (i.e., a barrier located at the high side of a super-elevated roadway will not concentrate and convey stormwater flows and therefore will not be mapped).</SPAN></SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></P></DIV></DIV></DIV>
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>This feature class contains WSDOT’s stormwater curbs.</SPAN></SPAN><SPAN><SPAN>A curb is the raised edge or perimeter barrier of a roadway surface or impervious paved surface such as a parking lot, foot path, or bike path. This feature class contains only curb segments actively concentrating and conveying stormwater flows (i.e., a curb located at the high side of a super-elevated roadway will not convey stormwater flow and therefore will not be mapped).</SPAN></SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></P></DIV></DIV></DIV>
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN><SPAN>This feature class contains WSDOT’s stormwater debris racks. </SPAN></SPAN><SPAN><SPAN>A debris rack is a structural device such as grates or rods used to prevent debris from entering a drainage structure, and can include a barred culvert end if the bars are intended to keep debris from entering the pipe. Additional terms used to describe this type of structural device are</SPAN></SPAN><SPAN>“trash rack” or “bee hive”.The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></P></DIV></DIV></DIV>
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>This feature class contains WSDOT’s stormwater discharge points. A stormwater discharge point is the </SPAN></SPAN><SPAN><SPAN>point at which WSDOT loses, or obtains, jurisdictional responsibility of concentrated stormwater from a constructed stormwater conveyance feature. This includes locations where stormwater infiltrates into the ground at the end of a constructed stormwater conveyance, or enters surface waters of the state through a constructed stormwater conveyance. </SPAN></SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas. Additional data were collected during stormwater retrofit review and mapping in Total Maximum Daily Load areas that are outside of the permit area.</SPAN></P><P STYLE="margin:0 0 14 0;"><SPAN>This feature class has five subtypes: Incoming, Land Surface, Managed System, Subsurface, and Surface Water.</SPAN></P><P><SPAN /></P></DIV></DIV></DIV>
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN><SPAN>This feature class contains WSDOT’s stormwater dispersion areas. A dispersion area is a </SPAN></SPAN><SPAN><SPAN>natural or engineered feature where stormwater is spread over a wide area and is located so as not to allow flow to concentrate anywhere upstream of a drainage channel with erodible underlying granular soils. A dispersion area must meet the requirements of BMP FC.01.1 (natural dispersion) or FC.02.01 (engineered dispersion) from the </SPAN></SPAN><A href="http://www.wsdot.wa.gov/Publications/Manuals/M31-16.htm"><SPAN STYLE="font-style:italic;"><SPAN>Highway Runoff Manual</SPAN></SPAN></A><SPAN><SPAN>. It must also be included in an as-built plan sheet as an indication that it has been approved for use as a best management practice (BMP) for a particular location.</SPAN></SPAN><SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></SPAN></P></DIV></DIV></DIV>
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P STYLE="margin:0 0 14 0;"><SPAN><SPAN>This feature class contains WSDOT’s stormwater ditches.</SPAN></SPAN><SPAN><SPAN>A stormwater ditch is a long, narrow excavation dug in the earth for drainage, having a top width less than 10 feet at design flow. This can include various linear conveyances constructed of rock, gravel, earth, concrete, asphalt, or other material using forms, machinery, etc. It can also include a convergence in gradients of impervious surfaces (e.g., in a parking lot) designed to concentrate and convey stormwater.</SPAN></SPAN><SPAN /><SPAN /><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></P></DIV></DIV></DIV>
BackSlope
(
type: esriFieldTypeString, alias: BackSlope, length: 30
,
Coded Values:
[Vertical: Vertical]
,
[Steeper Than 2 to 1: Steeper Than 2 to 1]
,
[In Between 2 to 1 and 4 to 1: In Between 2 to 1 and 4 to 1]
, ...1 more...
)
ForeSlope
(
type: esriFieldTypeString, alias: ForeSlope, length: 30
,
Coded Values:
[Vertical: Vertical]
,
[Steeper Than 2 to 1: Steeper Than 2 to 1]
,
[In Between 2 to 1 and 4 to 1: In Between 2 to 1 and 4 to 1]
, ...1 more...
)
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN><SPAN>This feature class contains WSDOT’s stormwater drainage areas. A drainage area is the </SPAN></SPAN><SPAN><SPAN>land surface area contributing runoff to a specific point in the stormwater system. This is determined as the sum of the total land surface area upstream from the point being analyzed and does not include areas within the polygon that are known to be or seen to be noncontributing to surface runoff. A drainage area is determined from local topographic maps and designed perimeter-confining features (e.g., curbs, concrete barriers, roadway crown, and designed gradient inflection lines in paved surfaces). It may have several different parts, respective to the impervious cover, soil, and vegetative ground cover types within the polygon.</SPAN></SPAN><SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></SPAN></P></DIV></DIV></DIV>
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN><SPAN>This feature class contains WSDOT’s stormwater drainage inlets. A drainage inlet is a </SPAN></SPAN><SPAN><SPAN>chamber or well allowing for the entry of surface runoff to a closed stormwater conveyance system. Inlet type is chosen based upon its hydraulic and interception capacity as well as depth of flow, grade, super-elevation, and placement.</SPAN></SPAN><SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></SPAN></P><P><SPAN>This feature class has eight subtypes: Catch Basin, Concrete Inlet, Drop Inlet, Dry Well, Grate Inlet, Manhole, Other, amd Unknown.</SPAN></P></DIV></DIV></DIV>
DrainageInletType
(
type: esriFieldTypeString, alias: DrainageInletType, length: 50
,
Coded Values:
[Type 2 With Flow Restrictor: Type 2 With Flow Restrictor]
,
[Type 2 With Baffle Type Flow Restrictor: Type 2 With Baffle Type Flow Restrictor]
,
[Type 1: Type 1]
, ...3 more...
)
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN><SPAN>This feature class contains WSDOT’s stormwater energy dissipators. An energy dissipator is a </SPAN></SPAN><SPAN><SPAN>method to reduce the total energy of flowing water; a mechanism that reduces velocity prior to or at discharge from an outfall in order to prevent erosion (see </SPAN></SPAN><A href="http://www.wsdot.wa.gov/publications/manuals/fulltext/M23-03/Chapter3.pdf"><SPAN STYLE="font-style:italic;"><SPAN>Hydraulics Manual</SPAN></SPAN></A><SPAN><SPAN>, Section 3-4.7</SPAN></SPAN><SPAN STYLE="font-style:italic;"><SPAN>;</SPAN></SPAN><SPAN><SPAN>see also </SPAN></SPAN><A href="http://www.fhwa.dot.gov/engineering/hydraulics/pubs/06086/hec14.pdf"><SPAN STYLE="font-style:italic;"><SPAN>FHWA Hydraulic Engineering Circular No. 14</SPAN></SPAN></A><SPAN><SPAN>). The WSDOT Stormwater Features Inventory Database should not document energy dissipators unless they occur at or near the end of a stormwater system, immediately prior to discharge.</SPAN></SPAN><SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></SPAN></P></DIV></DIV></DIV>
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN><SPAN>This feature class contains WSDOT’s stormwater flow restrictors. A flow restrictor is a </SPAN></SPAN><SPAN><SPAN>device such as an orifice or weir that restricts the volume of stormwater flow through or at the outlet of a structure. It may be associated with a “control structure” as part of a “flow restrictor system” (see Standard Plans </SPAN></SPAN><A href="http://www.wsdot.wa.gov/publications/fulltext/Standards/english/PDF/b10.40-00_e.pdf"><SPAN><SPAN>B-10.40</SPAN></SPAN></A><SPAN><SPAN>, </SPAN></SPAN><A href="http://www.wsdot.wa.gov/publications/fulltext/Standards/english/PDF/b10.60-00_e.pdf"><SPAN><SPAN>B-10.60</SPAN></SPAN></A><SPAN><SPAN>).</SPAN></SPAN><SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></SPAN></P></DIV></DIV></DIV>
BackSlope
(
type: esriFieldTypeString, alias: BackSlope, length: 30
,
Coded Values:
[Vertical: Vertical]
,
[Steeper Than 2 to 1: Steeper Than 2 to 1]
,
[In Between 2 to 1 and 4 to 1: In Between 2 to 1 and 4 to 1]
, ...1 more...
)
ForeSlope
(
type: esriFieldTypeString, alias: ForeSlope, length: 30
,
Coded Values:
[Vertical: Vertical]
,
[Steeper Than 2 to 1: Steeper Than 2 to 1]
,
[In Between 2 to 1 and 4 to 1: In Between 2 to 1 and 4 to 1]
, ...1 more...
)
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN><SPAN>This feature class contains WSDOT’s stormwater monitoring sites.</SPAN></SPAN><SPAN><SPAN>A monitoring site is a polygon feature that indicates the location and general boundaries of a site that has been selected for monitoring and is defined by WSDOT Environmental Services Office’s stormwater monitoring group.</SPAN></SPAN><SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></SPAN></P></DIV></DIV></DIV>
Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN><SPAN>This feature class contains WSDOT’s stormwater pipe ends. </SPAN></SPAN><SPAN><SPAN>A pipe end is the end point of a pipe, which is a sub-linear enclosed conveyance designed and constructed to convey flow; it has a clear opening of less than 20 feet (see </SPAN></SPAN><A href="http://www.wsdot.wa.gov/publications/manuals/fulltext/M23-03/Chapter8.pdf"><SPAN STYLE="font-style:italic;"><SPAN>Hydraulics Manual</SPAN></SPAN><SPAN><SPAN>, Chapter 8</SPAN></SPAN></A><SPAN><SPAN>). </SPAN></SPAN><SPAN>The majority of the data collected so far are within the Phase I and Phase II 2009 NPDES Municipal Stormwater Permit Areas.</SPAN></P><P><SPAN>This feature class has six subtypes: Culvert Pipe, Drain Pipe, Sanitary Sewer Pipe, Storm Sewer Pipe, Underdrain Pipe, and Unknown.</SPAN></P></DIV></DIV></DIV>