The City operates three water filtration plants to meet current and future demands of the metropolitan area’s 1.8 million consumers. Montebello Plants I and II are normally supplied by the Gunpowder Falls Reservoirs. Water from Loch Raven flows by gravity to the Montebello plants through a 12’ tunnel. The capacity of Plant I is 128 million gallons per day (MGD) while Plant II is rated at 112 MGD.

In times of drought, the Deer Creek Pumping Station supplements Loch Raven by pumping water from the Susquehanna 37 miles through a 9’ transmission main to Montebello. The third filtration plant, Ashburton, located on the west side of the City, is supplied by Liberty Reservoir through a 10’ wide tunnel 13 miles long. This plant can treat up to 165 MGD.

The City’s water supply system must not only meet everyday water demands but also the maximum projected needs of consumers. The combined safe treatment capacity of the three plants is over 400 MGD.

MONTEBELLO FILTRATION PLANT NO. 1 is located at 3900 Hillen Road, was placed in service in service in 1915 and can treat up to 128 million gallons per day of water from Loch Raven Reservoir or the Susquehanna River. The plant has two rapid mix chambers, four flocculators, four sedimentation basins, and 32 rapid sand filters. Treated water from the plant supplies the First Zone by gravity and other zones via pumping.

MONTEBELLO FILTRATION PLANT NO. 2 is located on the West Side of Hillen Road opposite of Plant No. 1. This facility began operation in 1928 and can treat up to 112 million gallons per day of water from either Loch Raven Reservoir or the Susquehanna River. Plant 2 has two rapid mix chambers, three flocculators, three sedimentation basins, and 28 rapid sand filters. This plant serves the First Zone by gravity and provides potable water to other zones using pumping stations.

ASHBURTON FILTRATION PLANT is located at 3001 Druid Park Drive. This plant was placed into service in 1956 and has a capacity of 165 MGD. The plant includes four flocculators, four sedimentation basins, and 20 rapid sand filters. Raw water supply for this plant is obtained from Liberty Reservoir. Drinking water flows by gravity from the Ashburton Plant to the Second Zone and is pumped to other zones in the Central System.