Name: Drinking Water Supply Management Areas (DWSMA)
Display Field: dsw_name
Type: Feature Layer
Geometry Type: esriGeometryPolygon
Description: New generation of Drinking Water Supply Management Areas for surface water intakes. This is the endorsed surface and subsurface area surrounding a public water supply intake that contains the scientifically calculated surface water protection area and is managed by the entity identified in a surface water protection plan. The boundaries of a DWSMA-SW are delineated by watershed and DNR-delineated catchment boundaries.
Name: Minneapolis, St. Paul, and St. Cloud Priority A DWSMA
Display Field: dsw_name
Type: Feature Layer
Geometry Type: esriGeometryPolygon
Description: The inner emergency management area is defined as the area in which the public water supply utility would have little or no time to respond to a direct discharge of contamination, other than to close the intake. Communication between emergency responders and the water utility will be essential for effective response action in this area. This is the area where a spill is most problematic because it is likely that a public water supply system would not have time to fill their reservoirs or adjust treatment technologies to address the spill. This area is based on an 8 hour TOT upstream of the intake based on high flow conditions. Additionally, contaminant threats, subwatersheds and areas of concern are considered and reflected in the delineated boundary of the Priority A area. The purpose of this area is similar to the Inner Emergency Response Area delineated for the SWA, but uses a detailed TOT study as part of the delineation process for the big three.
Name: Minneapolis, St. Paul, and St. Cloud Priority B DWSMA
Display Field: dsw_name
Type: Feature Layer
Geometry Type: esriGeometryPolygon
Description: This area is designed to protect water users from chronic health effects related to low levels of chemical contamination or the periodic presence of contaminants at low levels in the source water. This area should protect users from contaminants such as pathogens that may be 1) usually found at treatable levels in the source water, but 2) occasionally present an acute health concern within the Priority B Designation. The eventual goal is that the supplier will work cooperatively with others to prepare and implement management strategies for inventoried potential sources of contamination in the Priority B Designation. The area is based on TOT and watershed areas that contribute point and nonpoint contaminants upstream from the intake. Similar criteria and rationale described for the SWA Outer Source Water Management Area were also used to delineate and establish boundaries for the Priority B area.
Description: Defined as “the area in which the public water supply utility would have little or no time to respond to a direct discharge of contamination, other than to close the intake.” The area closest to the intake was designed to help the public water supplier address contaminant releases which present an immediate (acute) health concern to water users. The geographic area is defined by the amount of notification time the PWS would need to close the surface intake and a "buffer time" to accommodate unanticipated delays in notification and shut down. Three different sets of criteria were developed and used to delineate an ERA for different types of surface water bodies including: 1) rivers and streams, 2) lakes, and 3) mine pits. Information about the intake, water supply system, water storage capacity, treatment methods was also considered.
Name: Historical Outer Source Water Management Areas
Display Field: swa_name
Type: Feature Layer
Geometry Type: esriGeometryPolygon
Description: Defined as “the area where the impacts to drinking water from point and nonpoint sources of contamination can be minimized by preventive management.” This area was delineated to protect water users from long-term (chronic) health effects related to low levels of chemical contamination or the periodic presence of contaminants at low levels in the surface water used by the PWS. Criteria considered in defining this area included:
o Delineation of the outer source water management area is based on time of travel to respond to a potential contaminant threat and should consider the following criteria:
o contaminants or potential contamination sources that the public water supplier feels present a risk to the water supply;
o existing water resource management/protection programs that have identified areas of concern within a watershed or types of potential contamination sources that are of concern for overall water quality;
o the general types of land uses and contaminant sources believed to exist within the watershed, including the existence of major transportation routes (e.g., highways, bridges and railways) and pipelines;
o minor watershed boundaries within the watershed; topography; man-made and natural drainage patterns; wetlands or other contaminant attenuation features; and hydrology, including lakes, dams, etc.; and
o physical and chemical attributes of the source water being used.