Stormwater Planning Data Inventory
Stormwater Planning Data Inventory
Local and regional analysis of flooding issues relies upon regularly-updated geospatial information about a variety of indicators – including land cover/use characteristics, topography, and soils. The Stormwater Planning Data Inventory, a list of useful datasets, is shown below. Some of these datasets are used in the Guide to Flood Susceptibility and Stormwater Planning. Each record includes the most recently available vintage and provides a link to download or request the data. For additional information on available datasets, contact Kate Evasic (kevasic@cmap.illinois.gov or 312-386-8782).
| Source | Data Download / Request | Vintage | Description |
|---|---|---|---|
| CMAP | ArcHydro modeling outputs | 2017 | Includes hydrologically-corrected DEM, flow direction, flow accumulation, drainage lines, catchments, and depressions. See data packages for additional information. |
|
CMAP |
Elevation differential between property and nearest Base Flood Elevation (BFE) |
2017 | Identifies properties within a 1,500-foot buffer whose mean parcel elevation is within six feet of the nearest BFE. |
| CMAP | Impervious cover summarized by watershed catchment | 2017 | Summarizes percent imperviousness from the 2011 National Land Cover Database by watershed catchments contained in the 2012 National Hydrography Dataset “Plus.” |
| CMAP | Land Use Inventory | 2013 | Comprehensive parcel-based Land Use Inventory, containing 59 different use classes for over 2.5 million parcels. |
| CMAP | 2017 | Urban and riverine flooding susceptibility indexes (FSI) to identify priority areas across the region for flooding mitigation activities. Raw FSI values available upon request. | |
| CMAP | Topographic Wetness Index (TWI) | 2017 | Identifies flat areas with high flow accumulation where water is likely to pond using flow accumulation, slope, and various other geometric functions. CMAP's TWI is a simplified version of an Illinois State Water Survey effort for a portion of the region. |
| Counties | Streams and waterbodies, Cook, DuPage, Kane, Kendall, Lake, McHenry, and Will | Various | Hydrographic lines and polygons created and/or hosted by County GIS departments. |
| Counties; Municipalities | Building footprints, Chicago, DuPage, Lake, Will | Various | Overhead extent of building footprint as extracted or digitized from aerial photos. Footprints are known to exist for those areas with download/request links. For other areas, contact counties or municipalites to determine availability. |
| EPA | National Hydrography Dataset "Plus" | 2012 | Hydrologic data framework which incorporates the National Hydrography Dataset, the National Elevation Dataset, and the National Watershed Boundary Dataset. Includes HUC12 boundaries. |
| FEMA | National Flood Hazard Layer (NFHL) | Various | Database that includes location/extent of FEMA 100 and 500 year floodplains, including Base Flood Elevation lines. |
| ISGS; Counties | Light Detection and Ranging (LiDAR) Digital Elevation Model (DEM) data | Various | High-resolution LiDAR-derived elevation grids. |
| MWRD | 100-year Inundation Maps | Various | Modeling results from MWRD detailed watershed plans that delineate areas where flooding is expected to occur during a 100-year rainfall event. |
| MWRD | Combined Sewer Area Boundary | Various | Regulatory limits of unseparated sewer system, which conveys both wastewater and stormwater in the same pipes. Contact munipalities for availability outside of MWRD's jurisdiction. |
| NOAA | NOAA Atlas 14 | 2013 | Precipitation frequency estimates for selected durations and frequencies with 90% confidence intervals and supplementary information on temporal distribution of heavy precipitation, analysis of seasonality and trends in annual maximum series data, etc. |
| USGS | Historic Topographic Maps | 1889-1949 | Historic maps, including the location of streams and water bodies, created via field surveys or aerophotogrammetry. |
| USGS | Age of First Development | 2012 | Summarizes USGS National Water-Quality Assessment (NAWQA) Wall-to-Wall Anthropogenic Land Use Trends (NWALT) 1974-2012 land cover datasets into six categories: Prior to 1974; 1975 to 1982; 1983 to 1992; 1993 to 2002; 2003 to 2012; and Undeveloped/post-2012. |
| USGS | National Land Cover Database | 2011 | Medium-resolution land cover grid, including percent imperviousness and percent tree canopy. |