The Pleasant Valley Pipeline raw water intake carries Poudre River water to treatment plants to provide a secondary water supply for the City of Fort Collins and three area water districts. Ayres has completed multiple projects to improve the quality of the water entering the plants.
Sediment, leaves, pine needles, and pine cones clogged the flow control valves at the treatment plants, requiring costly manual cleaning many times a day. The City retained Ayres to design a technical solution that would eliminate the need for manual cleaning. Our team considered and rejected many options before recommending a traveling screen system commonly used in screening wastewater. Part of the continuously rotating screen catches debris while the other section is being cleaned by a high-pressure spray bar. The system clears up to 60 million gallons per day with a custom screen with a 1mm aperture to minimize the passage of pine needles and sediment.
Ayres also designed a Pleasant Valley Pipeline Forebay Sedimentation Pond to provide better quality raw water through the pipeline during turbid runoff so that the City can use as much Poudre River water as is available under its water rights.
The City’s water supply watershed experienced a massive forest fire during the summer of 2012, carrying the potential to generate highly turbid runoff impacting the City’s water supply. This project added a sediment forebay to the Pleasant Valley Pipeline diversion from the Pleasant Valley canal and included review and permitting through the State Engineer’s Office for Dam Safety.
Work on the sediment forebay included civil/site design, structural design, geotechnical investigation and design, hydraulic and sediment analysis, project coordination, and design documentation.