Baltimore's Department of Public Works is moving to supplement the city's water supply by drawing from the Susquehanna River after Loch Raven Reservoir — one of the primary sources serving the Baltimore metro area — fell to levels that triggered the region's backup sourcing protocol, according to a report this week from WBAL-TV.
DPW officials appeared on WBAL-TV's 11 TV Hill segment to explain the transition, confirming that the reservoir's lower-than-normal levels are the direct driver of the decision. The Susquehanna River has served as an emergency and supplemental source for the region before, but activating the arrangement reflects the cumulative impact of below-average precipitation across the watershed heading into fall 2026. Officials did not characterize the situation as a crisis, framing it instead as the planned contingency system working as designed.
Loch Raven is one of three reservoirs — alongside Prettyboy and Liberty — that supply the Baltimore region through the Back River and Montebello water treatment plants. The system collectively serves roughly 1.8 million people across Baltimore City and Baltimore County. DPW has not announced any mandatory conservation orders or service interruptions as of the time of the WBAL-TV segment.
What most general coverage of reservoir drawdown stories skips is the treatment and conveyance lag built into switching source water. The Susquehanna carries a meaningfully different turbidity and mineral profile than the stored reservoir water Baltimore residents normally receive — particularly after any upstream rainfall events that stir sediment. Water treatment plants must recalibrate coagulation and flocculation chemistry when source characteristics shift, which introduces a short window where finished water quality metrics can fluctuate before operators dial in the new inputs. That process is routine and well-understood by utility engineers, but it is part of why utilities have minimum storage thresholds at which they trigger the switch rather than waiting until reserves are nearly exhausted. Stored reservoir water acts as a buffer — both hydrologically and chemically — and running it low compresses the margin operators have to manage that transition cleanly. For households that store water at home, one of the underappreciated reasons water storage makes sense is precisely this treatment-chemistry transition period, not only outright supply failure.
