The comprehensive graphics and descriptions of Dakota County’s soils, rocks, and surface and ground waters will help you better understand the relationships between the surface and underground features of the County’s landscapes.
- Data Base Map – locations of all features and data utilized in producing the atlas maps.
- Bedrock Geology Map – the first sedimentary rock formation encountered at the surface or beneath soil cover.
- Surficial Geology Map – if rock is not exposed at the surface, this map depicts the unconsolidated materials (soils) that are present, as well as their origins.
- Depth to Bedrock and Bedrock Topography Map – if all the unconsolidated materials (soils) were stripped away, this map would represent the bedrock surface, including buried bedrock valleys. Colors indicate the approximate thickness of the unconsolidated materials (soils) cover over the bedrock.
- Quaternary Geology Map – depth to the shallow ground water table and the approximate thickness of the first aquifer (water-bearing formation).
- Bedrock Hydrogeology Map – depth to the bedrock ground water table (unconfined) or potentiometric surface (confined) of the Prairie du Chien-Jordan aquifer, the primary drinking water supply for the County.
- Sensitivity of the Prairie du Chien-Jordan Aquifer to Pollution Map – colors indicate how easily the primary bedrock aquifer may be contaminated [cool (blue) to warm (red)].
- Geology and Well Construction Map – indicates which ground water aquifers are recommended as safe drinking water supplies and how wells should be constructed properly to safeguard both the water’s use and it’s source.
- Geologic Resources Map – depicts and describes the locations of economic resources of sands, gravels, and sedimentary rock formations.