Wastewater Collections is the conveyance of wastewater from a business or residence to the wastewater treatment plant using underground pipes and lift stations. The CAWD collection system is comprised of approximately 81 miles of gravity sewers ranging in size from 6 inches to 27 inches in diameter, nearly 4 miles of force mains, 7 pump stations, and over 1,500 manholes.

The major trunk sewers include: (1) the Carmel Valley Interim Trunk Sewer, which serves Rancho Rio Vista, portions of Carmel Views, the Carmel Rancho Shopping Center, Hacienda Carmel, Del Mesa Carmel, Quail Meadows and outlying areas within Carmel Valley; (2) the Hatton Canyon Sewer, which joins the Carmel Valley Trunk sewer at the intersection of State Route 1, and Rio Road which serves the High Meadows, Carmel Knolls and portions of the Carmel Hills subdivisions; (3) trunk sewers which serve the city of Carmel and the Hatton Fields areas. The Carmel Meadows subdivision sewage is conveyed in a force main to the District treatment plant.

Pump stations are located at (1) the westerly boundary of Hacienda Carmel, (2) the westerly terminus of 8th Avenue (at Scenic Drive), (3) the intersection of Monte Verde Street and Sixteenth Avenue, (4) west side of Scenic Road approximately 200 feet north of Ocean View Avenue, (5) the end of Calle La Cruz (Carmel Meadows) (6) at the westerly boundary of the Carmel Meadows subdivision approximately 750 feet southwesterly of the Calle La Cruz pump station and (7) on the West side of Highlands Drive approximately 100 yards from Highway 1. All pump stations have been upgraded to allow remote monitoring and have capabilities for standby power and emergency bypass.

The District has an ongoing 5 year collection system capital improvement program and replaces or rehabilitates pipelines at the rate of 1,000 to 4,000 feet annually. Manholes are replaced as necessary.

The five person collection system maintenance crew cleans the entire system a minimum of once annually and performs routine repair work as necessary.