Challenge:

The City of Elko New Market is one of the fastest growing cities in Minnesota. Rapid development in this Scott County community has extended demands on the City’s entire infrastructure. The existing sewer system carries wastewater from users located west of downtown through the downtown business district in County Road 2 to the treatment plant located east of downtown. The projected sewer flow from the growth planned for the land west of downtown would exceed the capacity of the existing downtown sewer infrastructure to carry that flow. Most sewer systems are constructed when the community streets, businesses and houses are built such that there are minimal impacts to businesses owners and homeowners. The replacement of the existing gravity sewer collection system using the open cut method in County Road 2, in this older established business district with utilities, roads, varying topography and other features would have a major negative impact on the businesses.

Solution:

Thatcher Engineering prepared a feasibility study that evaluated several viable alternatives. Thatcher and the City found that the most cost effective and least invasive solution is to construct a 4,200 foot long 14-inch diameter sewer force main with 2,300 feet constructed using the horizontal directional drilling (trenchless technology) method and 1,900 feet constructed using the open trench method. The City then retained Thatcher to prepare plans and specifications and provide construction contract administration and observation services. S.M. Hentges and Sons, Inc., a utility contractor, constructed the project.