Connecticut Aquifer Protection Areas With Preliminary And Final Mapping

Connecticut's Aquifer Protection Areas Set contains polygon features delineating land contributing groundwater to public supply wells serving over 1000 people. The State of Connecticut Department of Energy and Environmental Protection (DEEP) approves and maintains the layer, which includes both Preliminary (Level B) and Final (Level A) mapping compiled from 1991 to the present. Data is compiled at a 1:24,000 scale and updated as final mapping becomes available.

Use Cases

• Analyze the spatial distribution of Preliminary versus Final Aquifer Protection Areas using the area type and status attributes.
• Assess regulatory coverage for public water supply wells by mapping polygon features representing protection zones.
• Model groundwater flow contributions to well fields using the detailed site-specific modeling underlying Final (Level A) mapping.
• Track the progression of wellhead protection efforts over time by comparing mapping compiled since 1991.

Strengths

• Polygon features are compiled at a standardized 1:24,000 scale.
• Data represents current conditions and is updated as final mapping becomes available.
• Temporal coverage spans from 1991 to the present, providing a longitudinal view.

Limitations

• The dataset contains both preliminary estimates and final modeled areas, introducing potential inconsistency in accuracy.
• Specific row counts and attribute details beyond area type and status codes are unknown.
• Coverage is limited to sand and gravel aquifers (stratified drift deposits) within Connecticut.

Provenance

Source

State of Connecticut Department of Energy and Environmental Protection (DEEP).

Collection Method

Areas were delineated by individual water utilities and submitted to DEEP for approval; final mapping is based on site-specific detailed groundwater flow modeling.

Time Range

1991 to present.

Freshness

Updated as final mapping becomes available; last platform update recorded as 2026-04-05.

Geography

State of Connecticut, USA.