Structure, outcrop, and subcrop of the bedrock aquifers along the western margin of the Denver Basin, Colorado

Bedrock aquifers underlie about 9,000 square miles in northeastern Colorado and are an important source of water for many urban areas, rural communities, farms, ranches, and industries. These aquifers outcrop and subcrop in a complex pattern along the western margin of the Denver Basin. In outcrop areas, the exposed bedrock aquifers are recharged by infiltration of precipitation. In subcrop areas where the bedrock aquifers directly underlie alluvial aquifers, either recharge or discharge may occur as the result of water movement between streams, alluvial aquifers, and the bedrock aquifers.