To increase drinking water system capacity and improve service reliability to customers in its Ellwood City service area, Pennsylvania American Water (PAW) made its largest infrastructure investment ever in northwestern Pennsylvania.
The recently completed, $50-million Ellwood Water Treatment Plant in Lawrence County replaces a 100-year-old structure. Whereas, the previous plant’s capacity was 5 mgd, the new plant features an 8-mgd raw water pump station (RWPS), expandable to 16 mgd, based on a 140-ft deep, caisson-type construction using deep-set vertical turbine pumps in a dry well on the west bank of the Beaver River.
Dual and single 24-in. raw water intake mains extend from the raw water pump station caisson to diversion chambers located on the north bank of the Connoquenessing and the west bank of the Beaver River, respectively. Two sets of dual, 24-in. raw water intake mains extend from the diversion chambers to the intake screen configurations.
Tunnels, bores and directional drilling included two 75-in. diameter microtunnels for the raw water, finished water and utilities accessing the new intakes, 60-in. micro-tunnel, a 30-in. horizontal directional drill and two 36-in. pipe bores. Tunneling and bore pipe construction crossing included four utility crossings of CSX and Norfolk Southern railroad tracks. An air burst intake screen system and sodium permanganate chemical system are housed in the RWPS and distributed to the intake locations through the 60- and 75-in. tunnels along with the 24-in. raw and finished water mains.
With expanded access and ample room to grow, the new Ellwood WTP enables Pennsylvania American Water to provide homes and businesses throughout the region with a reliable source of drinking water now and for decades to come.
Project Owner: Pennsylvania American Water Co.
Engineer: Gannett Fleming, Buchart Horn
Contractor: Reynolds Construction, Bradshaw Construction Corp.
Value of Trenchless Project (US$): $50 million