This layer depicts wetlands and wet areas tracked by the Metropolitan Mosquito Control District (MMCD) as potentially holding water long enough to support mosquito larval development (5 days). It was developed by MMCD for internal use and is not intended to imply jurisdictional wetland boundaries. It generally includes swamps, marshes, roadside ditches, small shallow ponds and other water-holding features down to 0.01 acre in size. It may include vegetated lake margins but does not generally include large bodies of open water.
All features were manually digitized from orthorectified digital aerial photography (for example, statewide FSA), and most have been field checked for approximate location and size at least once in the last 5 years. The actual extent of water will vary seasonally and annually with rainfall. The extent of water shown in this dataset tends to reflect conditions at the time the aerial photos were taken but may be modified based on field experience. Many sites are field checked during the spring, summer and fall, especially those treated frequently (see http://www.mmcd.org web map for access to inspection and treatment data).
Each feature has been assigned a unique number used within MMCD.