Service Area

The Brush Creek Wastewater Treatment Plant (WWTP) is a secondary treatment facility using primary clarification, fine bubble aeration, final clarification, and chlorine disinfection to treat the incoming wastewater flows.

The WWTP was designed for an average daily flow of 4.4 mgd and a peak flow of 15 mgd.  It currently operates at an average daily flow of approximately 4.04 mgd.

The treated effluent is discharged into Brush Creek through Outfall 001 which is near a portion of Brush Creek which is currently affected by acid mine drainage.  Brush Creek is a tributary of Turtle Creek, which eventually enters the Monongahela River.

The service area for the Western Westmoreland Municipal Authority (WWMA) includes the boroughs of Irwin, Manor, and North Irwin and portions of the townships of North Huntingdon, Penn, and Hempfield that are tributary to the WWMA interceptor sewers and waste water treatment plant (WWTP).  The Ardara/Cavettsville area is tributary to the Allegheny County Sanitary Authority (ALCOSAN) system.

The total service area encompasses approximately 12,500 acres in the western portion of Westmoreland County, Pennsylvania.  Considerable amounts of residential, commercial, and light industrial development, coupled with ever increasing residential development and large tracts of undeveloped land, are found throughout the service area.  Most of the new development within the service area has been in North Huntingdon and Penn Townships, with minor growth within a small area in Hempfield Township and along the Route 30 corridor in Irwin Borough.  The boroughs of Irwin, Manor, and North Irwin are older communities with little build-out potential.

The table below summarizes the number of equivalent dwelling units (EDUs) within each of the member municipalities from 2012 through 2022.  This table also shows the WWTP design populations and the EDUs for each of the municipalities.


Plant Design Population

Plant Design EDUs Total EDUs-2012 Total EDUs-2013 Total EDUs-2014 Total EDUs-2015 Total EDUs-2016 Total EDUs-2017 Total EDUs-2018 Total EDUs-2019 Total EDUs-2020 Total EDUs-2021 Total EDUs-2022
Hempfield 700 200 347 335 343 356 346 355 338 339 331 337 335
Irwin 5,000 2,700 2,595 2,580 2,519 2,545 2,577 2,481 2,495 2,461 2,441 2,457 2,470
Manor 2,500  714 1,289 1,300 1,326 1,337 1,347 1,369 1,369 1,412 1,417 1,406 1,413
North   Huntingdon-Brush Creek  20,000  5,714  6,394 6,321 6,261 6,360 6,481 6,440 6,437 6,383 6,275 6,249 6,386
North   Huntingdon-Ardara System  NA  NA  283 285 281 279 282 281 282 292 0 0 0
North Irwin  1,300  371 397 397 397 397 398 398 398 397 397 398 398
Penn  9,300  2,657 4,712 4,793 4,911 4,934 4,895 5,039 5,271 5,092 5,247 5,337 5,669
Total 38,800 12,356 16,017 16,011 16,038 16,208 16,326 16,363 16,590 16,376 16,108 16,184 16,671
Trafford Borough Contract Customers NA NA NA NA 48 48 48 48 48 48 0 0 0

All member municipalities own and maintain their respective collector sewers and pump stations. 

Cavettsville/Ardara System

The Cavettsville/Ardara System is a small portion of the WWMA’s sewer system that conveys wastewater to the ALCOSAN sewage treatment system from a portion of North Huntingdon Township and Penn Township.  This service area currently serves approximately 282 equivalent dwelling units located solely in North Huntingdon Township.  The Cavettsville/Ardara System also includes the Ardara Pump Station, which serves the Village of Ardara, a small residential community located along Route 993 in North Huntingdon Township.  WWMA services the community of Ardara, a small residential area of North Huntingdon Township.  The Ardara Pump Station, force main, and interceptors are owned, operated, and maintained by WWMA.  Collector sewers servicing the Ardara and Cavettsville areas are owned and maintained by the North Huntingdon Township Municipal Authority.  Due to increased costs related to ALCOSAN’s Consent Decree with the U.S. Environmental Protection Agency, the PA Department of Environmental Protection (PaDEP), and the Allegheny County Health Department; and WWMA’s Consent Order and Agreement with the PaDEP, a separate rate schedule for the Cavettsville/Ardara System was established on October 30, 2007 (refer to Resolution No. 2007-05). The Cavittsville-Ardara System was sold to the North Huntingdon Township Municipal Authority (NHTMA) on November 9, 2020. The Cavittsville-Ardara and Trafford Borough EDUs were transferred to NHTMA, at that time.