LIS Dredged Material Disposal Sites is a polygon feature-based layer that depicts the official locations of the four active (currently used) sites for depositing sediments approved for open water disposal in Long Island Sound. It does not include historic or discontinued disposal sites. The layer was compiled initially between 1999 and 2001 and depicts current conditions. Compilation scale is unknown. Attribute information is comprised of codes to uniquely identify individual features (locations of dredge disposal sites), encode the features, and cartographically represent (symbolize) these features on a map. This layer is updated as needed. Disposal activities in Long Island Sound are regulated by the following Federal statutes: the Clean Water Acts of 1977, the Coastal Zone Management Act, the Endangered Species Act of 1973, the Marine Protection, Research, and Sanctuaries Act of 1972, the National Environmental Policy Act of 1969, the Fish and Wildlife Coordination Act of 1958, and the Rivers and Harbors Act of 1899. In addition to Federal oversight, both Connecticut and New York also regulate open water disposal in the waters of Long Island Sound. In Connecticut, authority stems from the state's Structures, Dredging and Fill statute, the Tidal Wetlands statute, and the Connecticut Coastal Management Act. In New York, disposal is regulated through the Use and Protection of Waters Regulation, the Tidal Wetlands Use Regulations, the Coastal Erosion Management Regulations, the State Environmental Quality Review Act, the State Historic Preservation Act, the Waterfront Revitalization and Coastal Resources Act, and the New York Coastal Management Program. The practice of open water disposal in Long Island Sound utilizes one of the following management strategies: 1. Unconfined Open Water Disposal: A process by which material deemed to be environmentally safe is deposited at a given site. 2. Confined Open Water Disposal: A process by which sediments not suitable for unconfined open water disposal are deposited and then covered or "capped" with environmentally safe material. A variation of this method occurs when previous sediment mounds are used to form a ring into which material not suitable for unconfined open water disposal can be placed and then capped accordingly. The datalayer was originally created from information provided by: (1) Carey, D., Valente R., Murray P., and Rhoads, D. 1998. State of Connecticut Dept. of Environmental Protection Office of Long Island Sound Programs Dredged Sediment Management Study: Long Island Sound Dredged Material Management Approach. SAIC Peport No. 442, Science Applications International Corporation. Appendix F.; and (2) Various US ACOE DAMOS Monitoring Cruise Reports, 1991-2000. Updates for the 2005 edition included information from The Final Rulemaking and Response to Comments Document for the Final Environmental Impact Statement (FEIS) for the Designation of Dredged Material Disposal Sites in Central and Western Long Island Sound, US Environmental Protection Agency, May 19, 2005.
As part of the overall management approach, the four sites have been extensively monitored by the US Army Corps of Engineer's (ACOE) Disposal Area MOnitoring System (DAMOS) since 1977. Each site is briefly summarized as follows: Western Long Island Sound Disposal Site: The Western Long Island Sound Disposal Site (WLIS) is located 4.63 km south of Long Neck Point, CT. Dredged material has been deposited annually at the 5.35 km2 site since 1982 and consists mainly of fine silts and clays. Sensitive local resources and public concern limit disposal to material with only low levels of contamination, therefore, only unconfined open water disposal is employed. WLIS has been extensively monitored by the DAMOS program since the mid 1980's. Feature data updated as of 2005. Central Long Island Sound Disposal Site: The Central Long Island Sound Disposal Site (CLIS) was designated in 1979 and incorporates a previous disposal area, the New Haven Disposal Site, that was in use since 1972. Currently, CLIS encompasses an area of 8.26 km2 and is located approximately 10.37 km south of South End Point in East Haven CT. Because of its centralized location in Long Island Sound CLIS has been one of the most historically active disposal sites in New England. Characterized by predominantly silty material, CLIS mainly uses a confined disposal strategy, and the site has been monitored by DAMOS since 1977. Feature data updated as of 2005. Cornfield Shoals Disposal Site: The Cornfield Shoals Disposal Site (CSDS) was designated for dredged material disposal in 1976 and is located 6.12 km southeast of Cornfield Point, Old Saybrook, CT. Because of strong tidal currents in the area material deposited at CSDS is usually dispersed following release, often being transported outside the boundaries of the 3.42 km2 site. Therefore material disposed at CSDS cannot be capped and must be shown to have no adverse impact to the environment. Average annual disposal volumes at CSDS are much less than the other sites, and are typically characterized by sandy sediments. Disposal is restricted from June 1 through September 30 to protect lobster fishing and oyster spawning during the summer. CSDS has been monitored by the DAMOS program since 1978. New London Disposal Site: The New London Disposal Site (NLDS) is located 5.38 km south of Eastern Point in Groton, CT. The 3.42 km2 site is the shallowest of the four sites, ranging in depth from 14 to 24 meters, and has two distinct management areas within its boundaries. One is the 300 meter wide submarine transit corridor to allow passage for submarines to the US Navy base in Groton, CT, and the other is the New York-Connecticut state boundary line (approximately 0.43 km2 of the south east corner of NLDS lies in New York state waters.) Similar to CLIS, confined disposal methods are suitable for NLDS. Because of lobster fishing and oyster spawning during the summer, disposal is restricted at CLIS from June 1 through September 30. NLDS has been actively monitored by DAMOS since 1977.
ground condition
Long Island Sound Dredged Material Disposal Sites Sites represented as polygon features
Internal feature number. (Source: ESRI)
Feature geometry. (Source: ESRI)
Name of disposal area. Decodes the AV_LEGEND attribute. (Source: State of Connecticut, Department of Environmental Protection)
| Value | Definition |
|---|---|
| Western Long Island Sound Disposal Site | Decodes WLIS from the AV_LEGEND attribute. |
| Cornfield Shoalds Disposal Site | Decodes CSDS from the AV_LEGEND attribute. |
| Central Long Island Sound Disposal Site | Decodes CLIS from the AV_LEGEND attribute |
| New London Disposal Site | Decodes NLIS from the AV_LEGEND attribute. |
Upper range of water depth at site, in meters. (Source: State of Connecticut, Department of Environmental Protection)
Direction and distance to site from shore location. (Source: State of Connecticut, Department of Environmental Protection)
X value (longitude) of center coordinate in decimal degrees, NAD 83. (Source: State of Connecticut, Department of Environmental Protection)
Y value (latitude) of center coordinate in decimal degrees, NAD 83. (Source: State of Connecticut, Department of Environmental Protection)
Approved disposal method(s) for the site. (Source: State of Connecticut, Department of Environmental Protection)
| Value | Definition |
|---|---|
| confined | Contaminated dredged material may be capped (covered) with cleaner material |
| unconfined | Dredged material may not be capped (covered) with cleaner material, i.e., highly contaminated material is not allowed |
| confined , unconfined | Both disposal methods are allowed |
Lower range of water depth at site, in meters. (Source: State of Connecticut, Department of Environmental Protection)
Text field provding dimensions of disposal site, in km. (Source: State of Connecticut, Department of Environmental Protection)
Calculated area of polygon feature in square kilometers. Note, AREA_SQKM values are not automatically updated after modifying feature geometry (shape). Values must be recalculated after features are edited, simplified, generalized, clipped, dissolved, etc. (Source: State of Connecticut, Department of Environmental Protection)
A text field for symbolizing different feature types on a map (Source: State of Connecticut, Department of Environmental Protection)
| Value | Definition |
|---|---|
| WLIS | Western Long Island Sound Disposal Site |
| CLIS | Central Long Island Sound Disposal Site |
| CSDS | Cornfield Shoals Disposal Site |
| NLDS | New London Disposal Site |
Calculated perimeter length of polygon feature in kilometers. Note, LENGTH_KM values are not automatically updated after modifying feature geometry (shape). Values must be recalculated after features are edited, simplified, generalized, clipped, dissolved, etc. (Source: Stae of Connecticut, Department of Environmetal Protection)
Includes the four current dredged material disposal sites as polygon features in Long Island Sound. Information encoded about these features includes numeric and textual identification codes, site name, water depth information, locational information such as x and y coordinates in decimal degrees and direction and distance to the site, disposal method, and dimensions of the disposal site. Use AV_LEGEND to uniquely identify features and to symbolize features on a map. Use AREA_NAME to label features on a map.
79 Elm Street
LIS Dredged Material Disposal Sites depicts the location of the four current dredged material disposal sites in Long Island Sound. Use this layer with other similar map data such as NOAA navigation charts, Long Island Sound Bathymetry and Long Island Sound Geology. If using this layer with the 1:20,000 or 1:80,000 scale NOAA charts, note that the boundaries of the polygons do not exactly match those of the disposal sites depicted on the charts. Because the compilation scale of Dredge Disposal Sites is unknown, the accuracy of displaying this data with scaled data cannot be determined.
This source is the original data source (maps, reports) for the dredge disposal sites in Long Island Sound. DAMOS is administered by the U.S. Army Corps of Engineers. It is a multi-disciplinary environmental monitoring program managed by the Marine Analysis Section of the Regulatory Division. It provided verification of attribute inforamtion from Source 2 - LIS Dredged Sediment Management Study
This data source refers to all features combined in one statewide layer. Only active dredge disposal sites are in this layer. Historic disposal sites are not represented.
This report provided the spatial coordinates and summary information for the open water disposal sites in LIS
This source updated the location of the Central and Western Long Island Sound disposal sites as a result of the Federal Environmental Impact Statement for the Designation of Dredged Material Disposal Sites.
Feature digitizing and attribution - Based on data provided to the State of Connecticut, Department of Environmental Protection by SAIC, Inc. and the U.S. Army Corps of Engineers, this layer was digitized by entering the latitude and longitude coordinates of the corners of each disposal site. Degree and decimal minute data provided in the sources was converted to Connecticut State Plane Coordinates, NAD 83 and these values were used to create the bounding coordinates of the disposal polygons. Additional attribute information was manually entered.
Feature Updates - Using information from Source 4 - EPA Final LIS Environmental Impact Statement Rulemaking Response, the coordinates for the Central and Western Disposal sites were adjusted to the updated values. Degree and decimal minute data provided in the report was converted to Connecticut State Plane Coordinates, NAD 83 and these values were used to modify the bounding coordinates of the disposal polygons.
All attributes have valid values. Values are within defined domains. The Area_Name attribute is the English language equivalent of (decodes) the AV_LEGEND attribute. Attribute values were manually entered and verified.
The horizontal positional accuracy of this data is unknown.
The completeness of the data reflects the feature content of Source 1 - the Disposal Area Monitoring System (DAMOS) Maps, Source 2 - LIS Dredged Sediment Management Study, and Source 4 - EPA Final LIS Environmental Impact Statement Rulemaking Response. The LIS Dredged Material Disposal Sites layer is complete in the sense that it accurately reflects the data existing at the time the layer was created and updated by the State of Connecticut, Department of Environmental Protection. This data is updated as needed.
Polygon features conform to the following topological rules. Polygons are single part. There are no duplicate polygons. Polygons do not self overlap. Polygons do not overlap other polygons. Tests of logical consistency are unknown.
None. No restrictions or legal prerequisites for using the data. Once acquired, any modification made to the data must be noted in the metadata. When printing this information on a map or using it in a software application, analysis, or report, please acknowledge the State of Connecticut, Department of Environmental Protection as the source for this information.
79 Elm Street
| Data format: | in format Shapefile, Feature Class (version ArcGIS) |
|---|---|
| Network links: | http://www.ct.gov/deep |
The data distributor does not provide custom GIS analysis or mapping services. Data is available in a standard format and may be converted to other formats, projections, coordinate systems, or selected for specific geographic regions by the party receiving the data.
79 Elm Street