Flow augmentation for dissolved oxygen improvement in Chicago waterways

Alp, Emre
Even though treatment plant (water reclamation plant [WRP]) effluent concentrations meet the applicable standards and most reaches of the Chicago Waterway System (CWS) meet applicable water quality standards, dissolved oxygen (DO) standards are not met in the CWS during some periods. DO deficiencies particularly result in reaches subject to periods of limited flow, such as the upper North Shore Channel (NSC). Thus, an Use Attainability Analysis was initiated to evaluate what water-quality standards can be achieved in the CWS. Flow augmentation practices evaluated for the upper NSC included: i) a portion of the North Side WRP (NSWRP) effluent was transferred to the upstream end of the NSC, ii) the flow was transferred to and divided between two discharge points—one at the upstream end of the NSC and the other at 2.80 km upstream from the NSWRP. It was found that shifting the entire NSWRP effluent flow to the upstream end of the NSC could not achieve 100 percent compliance with a 4 mg/L DO criterion along the upper NSC. Another augmentation alternative was to add oxygen to the NSWRP effluent in the force main, and this transfer of oxygenated effluent was found to effectively improve DO in the upper NSC.
Citation Formats
E. Alp, C. MELCHING, and R. LANYON, “Flow augmentation for dissolved oxygen improvement in Chicago waterways,” 2009, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/37912.