ALCOSAN makes mapping related to the regional sewer systems and our region’s waterways available to the public. Each map below is updated quarterly. 

Collection System Map
(Updated 10/01/2024)

Identifies each location and related feature of ALCOSAN's sanitary and combined sewer outfalls, area sewersheds, and continuous flowing waterways within each sewershed.

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Sensitive Areas
(Updated 10/01/2024)

Identifies locations designated as sensitive areas.

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Sanitary Sewer & Combined Sewer Outfalls (Updated 10/01/2024)

Identifies sanitary sewer and combined sewer outfalls in ALCOSAN's system and outfalls in the regional collection system as reported by customer municipalities. (Updated on a quarterly basis as data becomes available.)

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Water Recreation Areas
(Updated 10/01/2024)

Identifies major water recreation areas in Allegheny County provided by the Pennsylvania Fish & Boat Commission.

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Impaired Waterways 

Identify continuous flowing streams and rivers listed as impaired by the Pennsylvania Department of Environmental Protection pursuant to Section 303 of the Clean Water Act:

Fish Consumption Designated Waterways
(Updated 10/01/2024)
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Aquatic Life Designated Waterways
(Updated 10/01/2024)
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Recreational Designated Waterways
(Updated 10/01/2024)
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Potable Water Supply Designated Waterways
(Updated 10/01/2024)
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GROW Cycles 1-8 Archive

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