Plateau Creek Pipeline Replacement

GEI was retained by the Ute Water Conservancy District to coordinate the integrated permitting and planning for the replacement of the 14.5mile-long Plateau Creek Pipeline and provided geotechnical investigation, final design and construction engineering services for the project. Plateau Creek Pipeline is the lifeline for over 60,000 rural and urban customers of the Ute Water Conservancy District (Ute Water) in Mesa County, Colorado.

The 30-year-old pipeline was inadequate to deliver peak water demands and was severely deteriorated due to corrosive soils which were unreliable in some areas due to landslides and creek erosion.

GEI’s decision support process involved working closely with Ute Water, several federal permitting agencies, and other consultants to develop a coarse screening of alternatives that was consistent with requirements of the Clean Water Act and the National Environmental Policy Act.

GEI then led the preparation of a third-party EIS that was approved by the Bureau of Land Management as a requirement for a BLM project right-of-way. Some of the key issues addressed in the EIS included impacts to four endangered fish in the Upper Colorado River, wetlands impacts, transportation impacts, and water quality issues.

GEI’s work during the design phase of the project included extensive geologic hazard and geotechnical evaluations along the pipeline route and the design of two 10-foot-diameter rock tunnels for portions of the pipeline.

GEI drilled over 130 borings, including some requiring helicopter access, that were over 700 feet deep. Key geotechnical issues addressed during the design include landslides, abandoned coal mine subsidence, collapsible soils, debris fans, highly corrosive soils, and high groundwater.

GEI provided resident construction engineering services for all geotechnical and tunnel construction aspects of the project. This work included tunnel mapping, assessment of temporary and permanent support for tunnels and portals, coordination of disputes, Review Board Meetings, and management support of construction engineering activities.

GEI performed field inspection of cut and cover portion of the pipeline, including welding, backfill, structural concrete and steel, cathodic protection, and general civil inspections.