Water System Model & Expansion

IMEG was contracted to develop a comprehensive hydraulic WaterCAD model for the onsite public water system serving 1500 inmates & 640 state correctional facility staff members at the Montana State Prison. The existing water system developed beginning in 1955 has three on-site public water supply wells.

The wells pump to three large storage tanks comprised of an 80,000-gallon buried concrete tank, a 190,000-gallon buried concrete tank, & a 282,100-gallon bolted steel tank. The distribution system is a pipe network with pipe diameters ranging from 1,100 feet of 3”, 8,500 feet of 4”, 13,700 feet of 6”, 15,000 feet of 8”, & 5,770 feet of 10” with pipes materials primarily comprised of PVC, galvanized steel, & asbestos pipe. There are 37 hydrants throughout the prison.

IMEG surveyed locations of water features including wells, water tanks, fire hydrants, valves & distributions mains, and installed temporary flow meters at all major building facilities & conducted flow & pressure tests at fire hydrant locations. A hydraulic model was developed for the entire system modeling peak flow demands & fire flow scenarios.

Based on findings, recommendations were made for capital im-provements, including main replacements, pump house upgrades, & development/implementation of Operation and Systems manuals.