Link to Home Page “All the water that will ever be is, right now.”
- National Geographic, October 1993

Home Page    

Watershed Profile

What is a Watershed?

A Watershed is an area of land in which all water sources flow into a common body of water. Small watersheds are part of larger watersheds, which in turn are part of even larger watersheds. [Source – Washington County Conservation District (PAWCCD)]

Thus, the Chartiers Creek Watershed in Washington County, Pennsylvania is part of a larger network of watersheds flowing all the way to the Gulf of Mexico!

To understand our watershed’s importance, though, we need to start at the beginning, at the source . . .

Watershed Geography

Chartiers Creek is a water source located in Southwestern Pennsylvania (USA). The Creek flows north from its headwaters in Washington County into Allegheny County, where it meets the Ohio River in Pittsburgh’s West End, three miles west of Downtown Pittsburgh. [Source -- "Ecology of Chartiers Creek Stream", Washington & Jefferson College Biology Department. Archived from the original on 2011-07-28.]

Chartiers Watershed - Tributaries

Map 1 – Chartiers Creek and its
tributaries form the watershed.

Source: US EPA Chartiers Creek Report

  Chartiers Watershed - Tributaries

Map 2 – Chartiers Creek Watershed, as situated
in Southwestern Pennsylvania.

Source: US EPA Chartiers Creek Report

Chartiers Creek Watershed is part of the Ohio River Watershed, which is part of the Mississippi River Watershed, which flows into the Gulf of Mexico. What happens in one stream in our watershed affects water quality on a much larger scale. [Source – PAWCCD website]

Chartiers Watershed - Tributaries

Map 3 – Ohio River Watershed,
showing course of Ohio River.

Source: US EPA. Chartiers Creek Report

  Chartiers Watershed - Tributaries

Map 4 – Mississippi River Watershed,
flowing into Gulf of Mexico.

Source: National Park Service, Mississippi

Within Washington County, the
Chartiers Creek Watershed is one
of fifteen main watersheds. Some
of these watersheds share territory
with neighboring Pennsylvania
counties or with West Virginia.

Watershed boundaries are formed
by the area’s topography, so
watersheds are usually divided
from one another by hills and
ridges. [Source – PAWCCD

  Chartiers Watershed - Tributaries

Map 5 – Washington County Watersheds

Source: Website of Washington County Watershed Alliance

Chartiers Creek Watershed consists of two sections:
  • Lower Section – Located mainly in heavily developed Allegheny County, with a small southern segment that is situated in Washington County (see map 6).

  • Upper Section – This section, located completely within central / north central Washington County, covers approximately 137 square miles, or 87,680 acres. Within this area, Chartiers Creek meanders 38.5 miles from its headwaters to the confluence with Little Chartiers Creek. Chartiers Creek and its tributaries comprise a total of 282 stream miles, flowing through a scenic area dominated by farms and forest. Washington City and Canonsburg are the main municipalities.

    Our watershed association (ChCWA) is concerned with all of the Chartiers Creek Watershed area located within Washington County, which includes the Upper Section, plus the small southern segment of the Lower Section.

Chartiers Watershed - Tributaries

Map 6 – Chartiers Creek Watershed,
showing Upper and Lower sections.

Source: Chartiers Greenway

  Chartiers Watershed - Tributaries

Map 7 – Profile of Chartiers Creek Watershed,
highlighting the Washington County Upper Section

Source: The development of this map was funded
by the League of Women Voters’ Citizen Education
Fund,under a grant from the Pennsylvania
Department of Environmental Protection.