DownloadA daily extract of the NPDES Structures dataset is available for download as a zipped file geodatabase.BackgroundAs a government agency that owns and maintains separate storm sewer systems, the Maryland State Highway Administration (SHA) is mandated to file a National Pollutant Discharge Elimination System (NPDES) permit with the Maryland Department of the Environment (MDE). The permit requires the inventory, inspection, and maintenance of SHA stormwater infrastructure. SHA is responsible for maintaining storm drain infrastructure on more than 5,000 miles of roadway statewide. SHA has developed a program consisting of SHA personnel, data managers, and subject matter experts to support the permit requirements and maintain these roadways. The tasks involved in the SHA NPDES data collection program are often completed by engineering consultants for SHA. The data are organized into a series of drainage systems with stormwater management facilities that are interconnected, allowing for flow-tracing function through distinct systems. A drainage system is defined as a series of storm drain structures or point features (i.e., manholes, inlets, endwalls) that connect hydraulically through conveyance features such as pipes and / or ditches. Closed and open storm drain structures are connected by pipe and ditch conveyance to create the drainage system. Stormwater management facilities (SWMF), also known as stormwater best management practices (BMP) are inventoried with the storm drain system. A system can include both open and closed storm drain features. StructuresPhysical stormwater structures to be identified and inventoried include headwalls, endwalls, cross culverts, pumping stations, stormwater risers and weirs, inlets, pipe connections, and manholes. Storm drain structures are represented as point features in the database. Several database features are included that are not existing physical structures, but are employed to facilitate connection of drainage systems in the database. For detailed descriptions of each feature, refer to the SHA Book of Standard for Highway & Incidental Structures, Category 3 “Drainage.” Storm drain structures within SHA ROW are inventoried. Information on private storm drain structures will need to be collected if a private system ties into SHA-owned storm drain features. The only structures that are not inventoried within SHA ROW are single residential driveway culvert end structures (See below for more details), bridge inlets, under drains, roof drainage, or other private tie-ins with the exception of the first or last structure from a private storm drain system and curb opening. If an under-drain pipe has an end structure (such as an endwall), then the structure is inventoried. Curb openings are only inventoried when affecting the drainage area for a BMP or major outfalls. If it is deemed necessary to include a curb cut in the database, the curb cut is captured as an inlet feature with comments identifying the feature as a curb opening. A curb opening is not a COG or COS inlet with an open back, but simply a cut in the curb where sheet flow is exiting impervious. The following are brief discussions of the structures in the data. See Chapter 2 of the Maryland SHA Stormwater NPDES Program SOP for more information, figures, and descriptions of each field. End / Head StructuresAn end / head structure is any structure at the upstream or downstream end of a culvert or pipe. These can include headwalls, endwalls, end sections, and projection pipes. Often the end / head structure is designated on the contract sheets and field verified. When contract plans are not available for a roadway, the SHA Book of Standard for Highway & Incidental Structures should be referenced if structure types are unfamiliar with field teams. Outfall areas are not to be inventoried, but will be analyzed during the inspection process. Headwalls (HW) are structures that are placed at the upstream end of pipes and culverts to provide a stable or hydraulically desirable entrance to the conveyance. Headwalls are usually concrete but can be constructed of wood or masonry, such as brick or concrete block. Wall structures on the upstream side of a culvert or pipe are inventoried as headwalls. Plan sheets may designate the upstream end of a pipe or culvert as an endwall, but these structures should be inventoried as headwalls. All wall-end structures at the upstream end of a pipe or culvert should be inventoried as headwalls. Endwalls (EW) are structures that are placed at the downstream end of pipes and culverts to provide a stable or hydraulically desirable exit to the conveyance. Endwalls are usually concrete, but can be constructed of wood or masonry such as brick or concrete block. All wall structures on the downstream side of a culvert or pipe are inventoried as endwalls. Plan sheets may designate the downstream end of pipe or culvert as a headwall, but these structures should be inventoried as endwalls. All wall-end structures at the downstream end of a pipe or culvert should be inventoried as endwalls. End Sections (ES) are structures that transition the ends of pipes into slopes and provide stability to the pipe entrances and outflows. End sections do not affect the hydraulic capacity or efficiency of the pipes. End sections can be constructed of concrete, metal, or plastic (HDPE). End sections can either be inventoried at the upstream or downstream end of a pipe. Projection Pipes (PP) are not physical structures but represent the upstream and downstream end of a pipe if an end structure on a pipe does not exist. Projection pipes are captured spatially as a feature and represent the ends of pipes. Inlet StructuresInlets are structures that collect storm drain runoff. Inlets convey the runoff to closed storm drain systems, open conveyance, or outfalls. There are many different types of inlet structures, and all are discussed in the SHA Standard Design Manual and should be reviewed prior to conducting an inventory. Spring heads are also inventoried as inlets. Inlets (IN) are hydraulic structure chambers below surface grade that collect storm drain runoff. An inlet either has a grate or open sides / curb to allow runoff to enter the storm drain system. Inlets are often constructed of concrete, masonry brick, or concrete block. Spring Heads (SH) are inventoried as inlets. Spring heads are inventoried only where they emerge and are connected to a storm drain system. Spring heads are inventoried because they provide evidence for the presence of ground water for dry weather flows during illicit discharge field screening operation. Spring heads may be identified from contract drawings or identified during the field inventory. Spring heads are mostly found in rural areas. Connection StructuresA connection structure is a storm drain structure that connects conveyance (pipes and ditches) within a system and is not an inlet, riser, weir, or pumping station. These can include manholes, ditch intersections, junction boxes, pipe connections, wye connections, capped inlets, pipe bends, and pipe directions. Because field crews are not required to open manhole lids and enter closed storm drain structures, no designation type is necessary for connection structures. All of the attribute data for these structures will be collected from contract drawings, including connection material and top of manhole elevations. The existence of connection structures should be field verified for spatial accuracy, even though the attributed data will be collected from contract drawings. For structures that are buried or paved over, a GPS point is to be recorded at the best estimated location in the field based on contract plan sheets. The verification of attribute table data for structures that cannot be verified in the field will be completed based on plan sheet information. This also holds true for structures that are buried or cannot be accessed; the attribute data should be obtained from plan sheets. Manholes (MH) are hydraulic structures that connect pipes through a system. They are used as access points to a system, to change direction or invert elevations for pipes, as a junction to change pipe size and / or material, and as a junction of multiple pipes to a single pipe. Manholes are frequently paved over or buried, but are still inventoried. Unless it is certain that the manhole does not exist, the manhole is inventoried. Manholes with lids that have designed holes to allow runoff to enter are inventoried as manholes and not inlets. Ditch Intersections (ID) are geographic representations of where ditches meet, begin, or end a system and are captured as point features. These features are used to define the extents of ditches. Junction Boxes (JB) are underground hydraulic structures that connect pipes through a system. They are used to change direction or invert elevations for pipes, to change pipe size and / or material, and to connect multiple pipes to a single pipe. Identifying junction boxes in the field is difficult because these structures are usually buried with no part of the structure exposed to the surface. Junction boxes are only inventoried from contract drawings and should never be assumed in the field, unless the field crew is certain the structure is a junction box. If the field crew suspects that pipes are merging together and no contract plans are available to confirm this, the connection should be inventoried as a pipe connection and not a junction box. Pipe Connections (PC) are locations throughout the conveyance of a system where two or more pipes connect. A pipe connection is also captured at the location where a closed storm drain pipe connects to a culvert or stream crossing. Wye Connections (YC) are hydraulic structures that join two pipes together within a system’s conveyance. Wye connections will be identified from contract drawings and should not be assumed in the field. Instead of assuming a wye

DownloadA daily extract of the NPDES Stormwater Management Facilities (SWMFAC) dataset is available for download as a zipped file geodatabase.BackgroundAs a government agency that owns and maintains separate storm sewer systems, the Maryland State Highway Administration (SHA) is mandated to file a National Pollutant Discharge Elimination System (NPDES) permit with the Maryland Department of the Environment (MDE). The permit requires the inventory, inspection, and maintenance of SHA stormwater infrastructure. SHA is responsible for maintaining storm drain infrastructure on more than 5,000 miles of roadway statewide. SHA has developed a program consisting of SHA personnel, data managers, and subject matter experts to support the permit requirements and maintain these roadways. The tasks involved in the SHA NPDES data collection program are often completed by engineering consultants for SHA.The data are organized into a series of drainage systems with stormwater management facilities that are interconnected, allowing for flow-tracing function through distinct systems. A drainage system is defined as a series of storm drain structures or point features (i.e., manholes, inlets, endwalls) that connect hydraulically through conveyance features such as pipes and / or ditches. Closed and open storm drain structures are connected by pipe and ditch conveyance to create the drainage system. Stormwater management facilities (SWMF), also known as stormwater best management practices (BMP) are inventoried with the storm drain system. A system can include both open and closed storm drain features.Stormwater Management FacilitiesStormwater Management Facilities (SWMFAC) are structural best management practices that temporarily store or treat stormwater runoff to reduce flooding, remove pollutants, and provide other amenities. Stormwater BMPs are impoundment areas that treat stormwater runoff to reduce flooding, remove pollutants, and provide other benefits such as wildlife attraction. Pollutant removal can be accomplished through retaining permanent pools of water, detaining water temporarily and then releasing it slowly, infiltrating runoff into the ground, filtering the water through a medium into the ground, or combining multiple treatments. Stormwater management facilities are represented as polygons in the database.If a stormwater BMP is receiving SHA runoff, the feature is inventoried, regardless of the owner. Attributes recorded for each stormwater BMP feature include type, location, status, and owner. Refer to the Maryland Stormwater Management Guidelines for State & Federal Projects - Volume I & II for stormwater BMP types and common features related to stormwater BMPs. Stormwater BMP design plan sheets will be supplied to the team and should be used as the source for the stormwater BMP inventory. Stormwater BMPs that are inventoried include, but are not limited to, ponds, wetlands, infiltration practices, filtration practices, and ESD BMPs. Stormwater BMPs are inventoried and recorded in the SWMFAC feature class. Due to the large number of different types, sizes, and shapes of these facilities, the SWMFAC table entries are not as standardized as the storm drain structure elements.SimplificationsThe simplification process flattens database tables that normalize attribute information, resulting in a dataset with all attributes but also many null fields when the attribute type is not relevant to the SWMFAC type. The simplified data are a snapshot in time of the production NPDES data, updated every night.PublishingThis service was last published by Elliott Plack on 9/6/2019 based on a materialized view created by John Shiu.

MDOT SHA Climate Change Vulnerability App is an ArcGIS Online (AGOL) web application which showcases geospatial data products related to climate change and the potential impacts to the State of Maryland's transportation infrastructure. The purpose of this application is to support MDOT SHA Senior Management, Leadership & Planning as they make efforts to avert and mitigate potential impacts of sea level rise that result from global climate change.The MDOT SHA CCVV App is a very robust application with an overwhelming amount of information available. The following resources should help users formulate a more focused approach to using the application based on their needs. The MDOT SHA CCVV Storymap provides a detailed walkthrough / tour of the CCVV app, and how users can take advantage of the various tools, data, and information available. Furthermore, there is also a MDOT SHA CCVV Instructional Video which provides users with additional guidance or reference when leveraging the app and its included functionality. MDOT SHA Climate Change Vulnerability App is owned & maintained by the MDOT SHA Office of Planning & Preliminary Engineering (OPPE) Innovative Planning & Performance Division (IPPD). For questions or more information please contact us @ IPPD@mdot.maryland.govData products showcased in this application are listed below and linked to each authoritative source: Nuisance Tidal Inundation / Flooding - Flood Depth Grids2020 Nuisance Tidal Inundation - Flood Depth Grid (Imagery Layer on ArcGIS Online for Maryland)2050 Nuisance Tidal Inundation - Flood Depth Grid (Imagery Layer on ArcGIS Online for Maryland)2100 Nuisance Tidal Inundation - Flood Depth Grid (Imagery Layer on ArcGIS Online for Maryland)For more information about the data, visit the Project Overview on the ESRGC website. Comprehensive Flood Modeling - MSL / MHHW Flood Depth GridsBased on the State of Maryland's latest available LiDAR data are Flood Depth Grids showing the projected impacts of Mean Sea Level (MSL) & Mean Higher High Water (MHHW) storm event scenarios for years 2015, 2050, & 2100. These flood depth grids include projected stillwater depth information (ft) for the following storm event scenarios: 0% Annual Chance Event (No.Storm Event)10% Annual Chance Event (10.Year Storm Event)4% Annual Chance Event (25.Year Storm Event)2% Annual Chance Event (50.Year Storm Event)1% Annual Chance Event (100.Year Storm Event)0.2% Annual Chance Event (500.Year Storm Event)For more information about the data, visit the Project Overview on the ESRGC website. Roadway Inundation (Flooded Roadways) Roadway Inundation / Flooded Roadways data consists of linear geometric features which represent the geographic extent of roadway segments projected to be impacted by Mean Sea Level (MSL) & Mean Higher High Water (MHHW) storm event scenarios for years 2015, 2050, & 2100. The following storm event scenarios are included: 0% Annual Chance Event (No.Storm Event)10% Annual Chance Event (10.Year Storm Event)4% Annual Chance Event (25.Year Storm Event)2% Annual Chance Event (50.Year Storm Event)1% Annual Chance Event (100.Year Storm Event)0.2% Annual Chance Event (500.Year Storm Event)For more information about the data, visit the Project Overview on the ESRGC website. Hurricane Florence ModelsHurricane Florence hit the State of North Carolina in September 2018 with devastating impacts. This event caused concern among coastal communities throughout the State of Maryland. The following data products have been developed to depict projected impacts to the State of Maryland from an event of similar magnitude. Roadway Inundation consists of linear geometric features which represent the geographic extent of roadway segments projected to be impacted by storm surge & flooding. Includes projected storm surge height / flood water depth information (ft).Inundated Parcels consists of polygon geometric features which represent the geographic boundary of property parcels that are projected to be impacted by an event of similar magnitude. Includes parcel ownership information and links to Maryland SDAT.Flood Depth Grid showing geographic areas throughout the State of Maryland that are projected to by impacted by storm surge from an event of similar magnitude. Includes projected storm surge height / flood water depth information (ft).For more information about the data, visit the Project Overview on the ESRGC website. Related DataA variety of other, climate change-related data products have been included for display in this application and can be found in this Related Data section. Data products showcased in this section are listed below, and linked to each authoritative source:MDOT SHA County Flood Statistics MapsAirportsAnnual Average Daily Traffic (AADT) LocationsBridge StructuresCHART Activity - State Emergencies (Action Events)CHART Activity - State Emergencies (Debris Events)CHART Activity - State Emergencies (Emergency Roadwork Events)CHART Activity - State Emergencies (High Water Events)Maryland Tide GaugesMaryland Stream GaugesMDOT SHA NPDES StructuresMilepoints (100th)Annual Average Daily Traffic (AADT) SegmentsMDOT SHA Emergency 667 EventsMDOT Roadway Lane Miles in FloodplainMDOT SHA NPDES ConveyanceFEMA Hurricane Evacuation RoutesMDOT SHA Maintained RoadsRoadway Access ControlRoadway Administrative ClassificationRoadway Federal Aid EligibilityRoadway Functional ClassificationRoadway Pavement ConditionAirport 4 Mile BufferCongressional DistrictsCounty BoundariesCritical AreasCritical Area TownsLegislative DistrictsMDOT SHA NPDES SWMFACMDOT SHA Parcel InventoryMaryland Property/Parcel BoundariesFEMA Effective FloodplainMDOT SHA District AreasMDOT SHA Maintenance Shop BoundariesMDOT SHA - Planning Level Right-of-Way (Tax Map Legacy)Metropolitan Planning Organizations (MPO) BoundariesMDOT SHA Right of WayMDOT SHA Context ZonesElevationSlopeTerrain (Hillshade)For more information, contact MDOT SHA OIT Enterprise Information Services:Email: GIS@mdot.maryland.gov