DELCORA – Utility Water Design, PA

Utility Water Design

Weston designed a new utility water system to replace the aging system at Delaware County Regional Water Authority (DELCORA)’s Western Regional Treatment Plant providing flexibility, redundancy, and greater operational flexibility.

DELCORA was experiencing several pipe failures in the utility water system that had caused outages at their sludge incineration process. Acting on the critical need of this system to maintain operations and the age of the piping to continue supplying utility water to the plant systems, DELCORA tasked Weston to evaluate and design upgrades to the system, so that it is more reliable and allows for operational flexibility.

Weston evaluated the existing system and determined the best solution: a looped piping system incorporating isolation valves at each building, point of use, and strategic locations in the piping network. The pipe arrangement also incorporated crossover tie-ins for isolation of each segment of the system without disruption of utility water to any of the users.

The treatment plant was constructed in the 1970s, and the facility had numerous underground obstacles. Weston performed a pipe route evaluation to determine the most economical arrangement while avoiding underground conflicts. We conducted an extensive geophysical survey and created test holes and drawing reviews to determine the extent of the underground obstructions.

Weston also performed a geotechnical evaluation of the subsurface soils and established design parameters, installation procedures, and performance specifications for the foundation and cradling structure to support the proposed utility water piping and associated infrastructure. The pipe foundation structure comprised a pile cap pipe supported by deep foundation system that minimized disturbance to neighboring soils and structures. Helical piles were selected as the most cost-effective foundation technology, saving our client project dollars. The helical piles were not only less expensive than other acceptable pile systems, the production rate during installation was faster, resulting in cost savings to DELCORA.

The design sequence of construction was prepared to both eliminate utility water shutdowns to critical systems and minimize shutdowns to non-critical systems. This was achieved by installing pipe tie-ins during normal shutdown periods, constructing critical segments of the pipe system to make appropriate tie-ins, and wet tap at certain locations.

Weston has supported DELCORA during the construction phase and provided oversight during the helical pile installation, the project will reach completion in the coming months.