Wastewater Collection Facilities

The existing wastewater collection systems for the Utility Solutions (US) service areas include infrastructure located in Elk Grove Subdivision, Northstar Subdivision, Galactic Park Subdivision, Rainbow Subdivision, Middle Creek Parklands Subdivision, Black Bull Subdivision, Gallatin Heights Subdivision and adjoining properties. All US gravity sewer infrastructure was installed between 2000 and 2008 and consists of modern materials including PVC sewer mains with four foot diameter manholes. To ensure proper construction of those improvements, the sewers were installed according to engineered plans and specifications and tested according to Montana Public Works Standard Specifications. The sewer mains were sized to handle flows from their respective subdivisions and adjoining properties. Any additional flows that may materialize for an existing main will come from future projects and will be subject to US and MDEQ review prior to approval.

Elk Grove gravity sewer mains drain into an existing lift station located at the edge of the wastewater facility property. The lift station consists of a buried concrete vault with at-grade self-priming centrifugal pumps. It was designed to handle the area associated with Elk Grove Subdivision and its neighbors. The lift station connects to a HDPE forcemain leading directly to the treatment plant. All other US gravity sewer mains drain to lift stations located at strategic points throughout the wastewater service area. Each lift station consists of buried concrete wet well and valve vault structures. The wet well contains rail mounted submersible pumps that can be removed without entry into the structure. The valve vaults house check valves, manual valves, and flow meters. Each lift station connects to HDPE or PVC forcemain piping that leads to the next upstream lift station and eventually empties to the treatment plant. The lift Station design capacities are shown in Table 1.

Table 1: Existing Lift Stations

C-1 LIFT STATION SECTION