Records indicate that the first attempt to establish public water supply in Baltimore was made in 1787 when the Maryland Legislative Assembly authorized the Baltimore Insurance Company to supply the town with water. This effort, along with subsequent other early efforts failed, however.

After incorporation in 1797, the City began to erect and maintain pumps in designated public thoroughfares. In 1803, an ordinance was passed, appointing a commission to collect numerous springs that formed the source of Carroll Run and to convey this supply to the City using pipeline. This effort failed, however due to right-of-way disputes.

In the early 1800s, a stock company known as the Baltimore Water Company was formed, land and water privileges were acquired and a reservoir was constructed at the southeast corner of Calvert and Center Streets to receive water from the Jones Falls. Additional reservoirs were later constructed at higher elevations and a distribution system was constructed. Eventually, the Water Company was sold to the City in 1854 for $1,350,000.

The City government continued to evaluate additional sources of supply to meet the needs of the growing municipality. After much study and debate, improvements were made to the Jones Falls supply in 1862 including the construction of Lake Roland Dam and Reservoir, the Jones Falls conduit, Lake Hampden, and Mount Royal Reservoir at a cost of $2,400,000. Lake Chapman (site of Druid Lake) was complete in 1865 to provide additional supplies.

Druid Hill Reservoir was constructed in 1873 to provide high service water supplies. As demand increased, coupled with recurring droughts, the City sought additional water supplies. Construction of a permanent supply from the Gunpowder Falls was completed in 1881 at a cost of $4,500,000.

Completed works consisted of construction of a dam across Gunpowder Falls at Ravens Rock formation of Loch Raven Reservoir, construction of a tunnel connecting the reservoir with Lake Montebello, and construction of a conduit connecting Lake Montebello to Lake Clifton.

Due to public health concerns, chlorination of the water supply was instituted in 1910 followed by construction of a water filtration plant at the Montebello site. Montebello Filtration Plant 1, situated on the east side of Hillen Road, was placed into operation in 1915 after a two-year construction period.

Construction of Loch Raven Dam was also completed in 1915 with the spillway crest extended to its present elevation in 1923. Annexation of additional land by the City in 1918 spurred the construction of Montebello Plant 2, which was placed into operation in 1928. Other major construction projects occurring the first half of this century included construction of the Montebello-Druid Lake conduit and Prettyboy Dam (1933), construction of the Gunpowder-Montebello Tunnel in 1941, and construction of the Patapsco - Montebello Tunnel in 1950.

In order to continue to meet the growing water demands, the Ashburton Filtration Plant, located on Druid Park Drive near Druid Hill Park in Baltimore City and Liberty Dam and Reservoir were completed in June of 1956. Additional major projects completed in the last half of the 20th century include several upgrades to the Montebello plants and the construction of the Deer Creek Pumping Station in 1966. Construction of this pumping station allowed the City to withdrawal water from the Susquehanna River.

During the first decade of the 21st century the Ashburton Filtration Plant underwent a massive $65 million upgrade and Loch Raven Dam was reinforced and refurbished, having it’s thickness doubled and storm gates installed. Lake Montebello was cleared of years of built-up sedimentation and refurbished for our visitors and recreational enthusiasts. Work continues on required covering/post-treating at open finished-water reservoirs. (Lake Montebello rededication).