The first water system in Missoula started from humble, but effective beginnings. It began with a Native American named "One-Eyed Riley" and his friend hauling water out of Rattlesnake Creek in a donkey cart. In 1871, the first actual system was begun with log pipes and wooden mains. The Missoula Mercantile bought the plant and added an electric plant. The Rattlesnake Intake Dam was built in 1901 with a settling basin capacity of 3 million gallons, and in 1906 it became Missoula Light and Water.

Missoula Light and Water Company was then purchased by the Montana Power Company in 1930. The system included water, electrical, city-central heating and trolley car systems. Missoula’s water needs were met by the Rattlesnake Creek until 1935, when five wells were added to augment fall and summer demands. In fact, the watershed was used until 1983, when the system was shifted to take advantage of our mighty aquifer. The Rattlesnake creek, however, is still maintained as an emergency back-up water supply. It is also being studied for reintroduction as a potable water supply through treatment.

In 1979, Montana Power Company created a separate subsidiary for the water portion of its company called Mountain Water Company. Park Water Company purchased Mountain Water Company from Montana Power in 1979. Now a subsidiary of Park Water Company, Mountain Water is an investor-owned utility regulated by the Public Service Commission. Included in the purchase were the water rights to eight Rattlesnake Lakes, the Rattlesnake Creek and Intake Dam. It also included the water system of the small rural town of Superior, located in the mountains 60 miles west of Missoula. This system was has now been sold to the Town of Superior.

In recent years, Mountain Water Company acquired two water systems serving the South portion of Missoula – The Clark Fork Water Company and Linda Vista Water Company. During the fall of 2000, Mountain Water acquired the system at Fort Missoula, serving businesses such as the Forest Service, Historical Museum, Army Reserve, National Guard, and Bureau of Land Management. Using approximately 9000 feet of PVC pipe, the Fort Missoula system was tied into Mountain Water's system. Two pressure-reducing stations were installed to lower the pressure into the existing zone. In May of 2001, Mountain Water acquired a water system serving the North Reserve and lower Grant Greek areas; formerly known as the Missoula Water Works system. Our Missoula system now boasts 37 wells, 45 boosters, 24 storage facilities, and has a storage capacity of approximately 9,344,000 gallons.