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Cornell Lake Source Cooling

Cornell University's Lake Source Cooling (LSC) facility draws water from Cayuga Lake and uses it to cool campus buildings before discharging back into the Lake. Although the system operates as a "closed loop" system (i.e. no water or contaminants are added to the water), the discharge from the cooling facility does contains phosphorus that was in the water when withdrawn from the Lake. The NYSDEC has issued a State Pollutant Discharge Elimination System (SPDES) permit to regulate the levels of phosphorus and other substances in the facility discharge. Specifically the permit includes interim limits for phosphorus, pending the results of the related Cayuga Lake water quality study.

Increasing concentrations of phosphorus and chlorophyll throughout the Lake have led to a decline in water quality in Cayuga Lake over the past decade. Phosphorus has been linked to increases in algae and reductions in dissolved oxygen necessary for the support of fish. The extent to which the LSC facility contributes to the decline in Cayuga Lake's water quality - relative to area wastewater discharges, agricultural runoff, stormwater contribution and other sources - is currently unknown. But under the terms of the final permit, Cornell University will fund a $2.1 million study and develop a water quality model to characterize and quantify sources and impacts of the phosphorus. The effort will support DEC's development of a Total Maximum Daily Load (TMDL) plan, which will provide a road map for phosphorus reductions in the Lake. The permit also includes requirements for other studies and reports aimed at the protection and improvement of water quality in the Lake. As these products are submitted, they will be included in the outline below.

Date Deliverables and Other Items (with Links)
March 2013 Initial SPDES Permit for Cornell University Lake Source Cooling (LSC) Facility (PDF, 736 KB) See also Modified Permit (Mar 2016)
March 2013 NYSDEC Response to Public Comment on Cornell LSC Facility SPDES Permit (PDF, 251 KB)
March 2013 Cayuga Lake Modeling Project Quality Assurance Project Plan (QAPP) for Phase 1: Monitoring and Modeling Support for a Phosphorus/Eutrophication Model for Cayuga Lake (PDF, 2.2 MB)
Jan 2013 Workplan - Lake Source Cooling Outfall Redesign (PDF, 954 KB)
Jan 2013 Cornell University Chilled Water Best Management Practices Program (PDF, 354 KB)
Jan 2013 Cornell University LSC Proposed Workplan for an Entrainment Characterization Study (PDF, 332 KB)
Dec 2014 Status Report 1: Outfall Redesign Study (PDF, 1.75 MB)
Dec 2014 Phase 1: Monitoring and Modeling Support of Phosphorus/Eutrophication Model for Cayuga Lake - Executive Summary (PDF, 332 KB); the Full Report is available on the Cornell University/Cayuga Lake Modeling Project Website
Jan 2015 Cornell University Chilled Water Best Management Practices Program - 2014 Annual Report (PDF, 785 KB)
Jan 2015 Cayuga Lake Modeling Project Quality Assurance Project Plan (QAPP) for Phase 2: Monitoring and Modeling Support for a Phosphorus/Eutrophication Model for Cayuga Lake (PDF, 1.2 MB)
April 2015 Cornell University LSC Entrainment Characterization Study (see Oct 2015 Final Biomonitoring Status Report below)
Aug 2015 Status Report 2: Outfall Redesign Study (PDF, 816 KB)
Oct 2015 Cornell University LSC Final Biomonitoring (Entrainment Characterization Study) Status Report (PDF, 1.2 MB)
Jan 2016 Cornell University Chilled Water Best Management Practices Program - 2015 Annual Report (PDF, 343 KB)
March 2016 MODIFIED Final SPDES Permit for Cornell University Lake Source Cooling (SC) Facility (PDF, 457 KB)
April 2016 Status Report 3: Outfall Redesign Study (PDF, 2.65 MB)
Oct 2016 Cornell Lake Source Cooling Facility Outfall Redesign Study Final Report (PDF, 2.6 MB) and Appendix A (PDF, 4.8 MB) See also NYSDEC Comments on the Final Report (Feb 2017)
Dec 2016 Phase 2 Final Report: A Phosphorus/Eutrophication Water Quality Model for Cayuga Lake, NY (PDF, 5.1 MB)
Jan 2017 Cornell University Chilled Water Best Management Practices Program - 2016 Annual Report (PDF, 340 KB)
Feb 2017 NYSDEC Comments on the Cornell Lake Source Cooling Outfall Redesign Final Report (PDF, 84KB)

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