Horizontal Collector Well #2

Horizontal Collector Well #2

Location: Olathe, Kan.

Client: City of Olathe

Completion Date: September 2002

In response to declining yields in its 40-year-old well field, and based on the success of its first collector well, the city of Olathe, Kan., completed a second horizontal collector well to replace 10 old wells and maintain capacity for its system.

Burns & McDonnell conducted a hydrogeologic investigation along the Kansas River using one of the city's existing wells, and located a site suitable for the second horizontal collector well. Due to the large quantity of water required for this project and the degrading water levels in the Kansas River valley aquifer, a horizontal collector well was more cost-effective than replacing the old vertical wells in a well field.

A site was identified, and a 7-MGD horizontal collector well was constructed. Burns & McDonnell and Collector Wells International provided design-build services for the complete well installation. The horizontal collector well has a 16-foot inside diameter caisson that extends approximately 65 feet below the ground surface. Four horizontal lateral well screens extend an average of 200 feet from the caisson and under the Kansas River.

The well was completed with a pump station that includes three-multistage vertical turbine water pumps with enclosed line shafts and above surface discharge. Two 300 hp pumps have variable speed drives, and the third 500 hp pump has a constant speed drive. The pump station is complete with 100 percent power backup system provided by an engine generator.