WSP Water Solutions

Water Supply, Dams, Reuse and Storage 

Puerto Rico East Central Water Supply – Valenciano Dam Puerto Rico Aqueduct and Sewer Authority (PRASA) | Juncos, Puerto Rico ■ Large, high-hazard roller compacted concrete (RCC) gravity dam design ■ Seismic structural analysis and design ■ Comprehensive water system integration This project aims to address the need for a reliable drinking water supply in the east-central Puerto Rico with the Valenciano Dam, a proposed dam that spans the Río Valenciano. The dam will form the new Valenciano Reservoir to significantly increase water storage, providing resiliency against droughts. The 125-foot-tall, 1,1000-foot-long structure features a gated spillway and an innovative sediment sluice tower to provide sustainable reservoir sedimentation operations. Our team performed design investigations, including sedimentation modeling, computational fluid dynamics hydraulic modeling, hydraulic physical modeling, seismicity analysis, seismic stability modeling and an extensive RCC testing program. Other design features for the dam include the downstream energy dissipator, river transitions, a river bypass/low level outlet structure, multi-level raw water intake tower, operations and control building, gate operations supervisory control and data acquisition system, and an access bridge across the crest of the dam.

Russell Creek Reservoir – Etowah Dam

Niskey Lake Dam Rehabilitation

Etowah Water & Sewer Authority (EWSA) | Dawson County, Georgia

Ruby Collins Construction | Atlanta, Georgia

■ Strategic water supply upgrades ■ New earthen fill pumped storage reservoir ■ Environmental impact statement

■ Design and permitting services ■ Design-Build dam rehabilitation ■ Increased dam resilience

Northern Georgia’s rapid population and infrastructure growth created an urgent need for improved water supply sustainability. However, environmental protections for endangered species in the Etowah River limited new construction in the area. To address this challenge, WSP developed a new offline pumped storage water supply reservoir, the Russell Creek Reservoir. WSP designed a 110-foot-tall earthen dam, creating a 1.4-billion-gallon reservoir to secure long-term water supply. The system included a river pump station, 3-mile raw water pipeline and upgraded treatment plant, delivering up to 17.3 million gallons per day. This reservoir is designed to draw flows from the Etowah River during times of excess flow, with water returned to the river during low flow and drought conditions. These operations will provide long-term sustainability to the drinking water supply yield and adequate environmental flow conditions for protection of the Etowah Darter and Amber Darter endangered species.

WSP was the lead designer for the design-build rehabilitation of the Niskey Lake Dam, a 35-foot-high earthen embankment dam originally constructed in 1929. The team provide full design and permitting services for upgrades to the dam embankment and spillway. The dam was reclassified as a High Hazard Structure by the Georgia Department of Natural Resources Safe Dams Program, triggering the need for significant upgrades to meet modern safety and regulatory standards. The rehabilitation design included a 66-foot-wide concrete overtopping spillway constructed through six large culverts, allowing a residential street to safely pass over the dam crest. This design not only enhanced spillway capacity, but also improves community access and resilience. WSP coordinated permitting requirements with the Georgia Safe Dams Program, Georgia Environmental Protection Division and the US Army Corps of Engineers. The project addressed critical safety concerns while preserving the dam’s functionality and integrating it into the surrounding neighborhood.

Page 13