Water Resources Engineering (WRE) connects engineering hydrology and hydraulics with global, economic, environmental, and societal issues. Our student Nick Shrimpton makes this connection here…

The news article titled “Aging Sewers Impacting Urban Watersheds” was reported by World Water Magazine on March 12, 2013. The article describes the deterioration of Pittsburgh’s sewage infrastructure and how raw sewage is leaking into the surrounding Nine Mile Run watershed as a result.  This issue falls in both the hydrology and hydraulic domain of water resource engineering because it deals with the diminishing water quality in local streams and rivers as a result to crumbling waste management systems. It is estimated that approximately 12% of Pittsburgh’s total sewage leaks into the watershed, causing about 10-20 tons of nitrogen to be discharged annually.  The article reports that this sewage is depleting the oxygen levels in the Monongahela River and its tributaries. After critical analysis of this article, I believe that its local focus fails to provide the harmful effects this issue may have on a national level.  The article also strictly focuses on the recognition of the problem instead of proposing any ideas toward a solution.

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Figure 1 – Raw sewage discharge into a dried water channel in Pittsburgh

Water Resource Engineering includes the interconnectivity of the management of hydrology and hydraulic systems to optimize the use of water supplies.  The issue discussed in this article fits to a broader spatial and economical context. The harmful effects of sewage discharge into a watershed are commonly known amongst Americans. However, recognition of the environmental implications from this problem on a national level requires further analysis.  The Monongahela River flows into the Ohio River to the Mississippi River, which is eventually discharged into the Gulf of Mexico.  While Pittsburgh’s leaking sewers are not completely at fault, they certainly contribute to the hypoxic zone at the estuary in Louisiana. Economically, the complete repair of the sewer systems in the city is unfeasible.  Replacement of inadequate wastewater systems would be an estimated $3.6 billion cost to the city, raising the annual sewage bill about $600 per household according to the proposed “Alcosan Plan” (2012). The leaking sewage problem in Pittsburgh is one in which both the environmental and socio-economical impacts must be carefully considered and weighed out before a remediation plan is put into effect.

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Figure 2 – Hypoxic Zone in the Gulf of Mexico around Mississippi estuary

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