The day-to-day operation of MSD’s wastewater infrastructure is much like a manufacturing process, consisting of inputs, finished products, and by-products. In our sewage treatment system, the primary inputs include wastewater, energy, and chemicals. From these “raw materials,” we generate one finished “product”: treated water in compliance with water quality regulations. Our wastewater treatment processes also generate a variety of by-products, including sludge, air emissions, GHG emissions, odors, solid wastes, and recyclable wastes.
Our environmental footprint consists of the materials and energy we consume, the wastes and emissions we produce, and the quality of the treated water we produce. Any improvements we can make in treatment processes, efficiency, conservation, and waste and emissions reductions will, therefore, reduce our environmental footprint. However, our number one contribution to our region’s environmental health is returning clean water to local waterways.
In addition, meeting the requirements of the federal Consent Decree to reduce overflows from entering streams, creeks, and rivers is a critical component of improving our region’s water quality as well as public health. Performance indicators related to the Consent Decree are published separately, at www.msdgc.org and www.projectgroundwork.org.
In this section, we present a variety of sustainability indicators relating to our operational and environmental performance. They have been selected to represent products, inputs, and by-products, as shown to the right.
Continuous Process Improvement Teams
MSD’s Continuous Process Improvement teams were formed several years ago in the wastewater treatment division. These teams look at influent screening, liquid stream, and solid stream processes optimize resources and reduce wastes. Improvements are measured using defined indicators, some of which apply to material and energy use:
- Electrical usage for aeration
- Electrical usage for secondary by-pass
- Electrical usage for blowers
- Natural gas usage for incineration
- Hypochlorite usage
- Polymer usage
Effective measuring and management of these areas allow MSD to streamline treatment processes and reduce operational costs.