The City of West Fargo had grown rapidly (75 percent in the past ten years), stretching the capacity of the existing sanitary sewer systems. As a result, the city experienced multiple sewer system malfunctions leading to increased maintenance and burden to city personnel. Frequent lift station equipment failures and force main ruptures on the old system in the north central part of the city increased maintenance costs and consumed resources beyond normal operating conditions. The city recognized the need for immediate sanitary sewer upgrades and acted upon it with a larger capacity, minimal maintenance, and a more energy efficient sanitary sewer system. With this underground work, deteriorating city streets were also able to be improved at a relatively low cost.
The city developed a concept to replace undersized and outdated collector pipes, force mains, and mechanical lift stations with a new gravity sanitary sewer system to accommodate the higher demands. With the new gravity system, the capacity, efficiency and reliability would be greatly increased while minimizing regular maintenance burdens and costs to the City.
The project consists of constructing deep collector gravity sewer, bringing raw sanitary water to a newer, existing 36-inch PVC deep mainline (installed in 2009). This mainline conveys flows to the city’s main regional lift station, Northside Regional Sanitary Lift Station, sized to discharge large volumes to the city lagoons. The replacement of the old and collapsing force main consisted of 8,000 feet of new 24-inch and 18-inch PVC piping acting as gravity collectors branching out from various points in the area. Regionally, the complexity of the force main system was simplified with the abandonment of four lift stations and over one mile of force main which increased the overall efficiency and reliability of the system in the area.
This project provided a much needed upgrade to an aging part of the city’s sewer system. The new system is more efficient and reliable with gravity collection and more accessible with less maintenance for the City of West Fargo. The improvements to the Center Street roadway also came at a necessary time to improve the street’s condition and safety in the area. The project was completed on time and was a success; the City’s infrastructures were improved, burdens on city staff were alleviated, and the client was thrilled and grateful with the overall end product.
Fully funded through a city revenue bond