Case Study: Water and Wastewater Utilities Planning for Climate Change CAPITAL REGION WATER HARRISBURG, PENNSYLVANIA Background Capital Region Water (CRW) provides drinking water services to over 60,000 and wastewater services to over 130,000 residents and businesses in the city of Harrisburg, Pennsylvania and its neighboring communities. CRW's primary drinking water source is the DeHart Reservoir, a 6 billion gallon reservoir located 25 miles north of Harrisburg which is fed by Clarks Creek. The Susquehanna River is a secondary water source for CRW that can be used when additional water supply is needed. CRW's water treatment plant, the Dr. Robert E. Young Water Services Center, is rated up to 20 million gallons per day (MGD) but usually experiences a demand of 8 MGD. CRW also operates the wastewater and stormwater system comprised of both separate sanitary and storm sewer facilities and a combined sewer system, which includes several pump stations and treats nearly 20 MGD of wastewater from Harrisburg and other neighboring municipalities at their advanced wastewater treatment facility (AWTF). Climate Threats Flooding from intense precipitation and rising river levels is of concern to CRW. The city of Harrisburg was previously affected by severe storm events, including Hurricane Agnes in 1972, Tropical Storm Lee in 2011 and river flooding from snowmeltthat has compounded with increased spring precipitation. During Hurricane Agnes, nearby river levels reached 36 feet, causing significant inundation at the AWTF. During Tropical Storm Lee, water rose onto the AWTF property, flooding some of its access roads. The AWTF, wastewater pumping stations, DeHart Reservoir dam and raw water intake, as well as an alternate raw water intake facility on the Susquehanna River are at risk from damage due to flooding. Conversely, CRW also considered the threat of low water levels under a potential drought scenario. CRW is concerned that such extreme events would become more frequent under a changing climate. Planning Process To better understand the vulnerability of their drinking water and wastewater infrastructure and operations, CRW assessed potential climate change impacts using the U.S. Environmental Protection Agency's (EPA) Climate Resilience Evaluation and Awareness Tool (CREAT). The CREAT assessment brought together individuals from EPA and various departments within CRW to think critically about potential climate impacts, prioritize assets and consider possible adaptation options. Adaptation Measures CRW considered the potential consequences of extreme flooding and drought events on their drinking water and wastewater utility infrastructure and operations. To assess each of these potential threats, CRW considered how potential adaptive measures would help lower consequences. See the table below for potential adaptive measures that were considered. Harrisburg, Pennsylvania Case Study — Page 1 SEPA ------- Case Study: Water and Wastewater Utilities Planning for Climate Change TYPE POTENTIAL ADAPTIVE MEASURES Wastewater Pumping Stations AWTF DeHart Reservoir Back-up power for critical assets to prevent service loss during extreme events Flood risk management plan to mitigate risks to the treatment facility, pumping stations and collection system Elevate electrical components and controls to mitigate flood risk Replace pumps with those with submersible motors to prevent flooding damage Backflow prevention Infiltration reduction during severe rain events Separate combined sewer system to reduce sewer overflows Green infrastructure at CRW facilities for demonstration and public outreach and throughout the community and public spaces Increase wastewater treatment capacity to mitigate flooding risks Combined sewer overflow strategies to mitigate risks posed by severe rain events and flooding Infiltration reduction during severe rain events Improve drought contingency plan to address impacts from water quality changes or dropping water levels in reservoirs Leakage reduction Demand management Reduced conservation release through regulatory flexibility Contact Information For more information regarding CRW's climate adaptation planning, contact Tanya Dierolf at Tanva.Dierolf@capitalreqionwater.com. Harrisburg, Pennsylvania Case Study — Page 2 &EPA Office of Water (4608T) EPA 800-Q-15-010 December 2015 ------- |