The city of Baltimore and the Susquehanna River Basin Commission have settled their decade-long dispute over the city’s use of the river’s water. The settlement allows the city to withdraw up to 250 million gallons of water per day from the river, but that allotment would decline to 64 million gallons daily during times of severe drought.

The agreement requires the city to meet certain water conservation requirements, establish drought period restrictions and participate in the development of a management plan for the reservoir behind the Conowingo Dam from which it draws water.

Also, the city acknowledged that the SRBC has jurisdiction over the use of the river, and will withdraw its legal challenge to that authority.

The dispute has been going on for nearly a decade, but had come to a head in recent years as the SRBC, concerned about increased demands for water from the Susquehanna — the largest source of fresh water to the Chesapeake — has become more active in regulating water use, and especially the transfer of its water to users outside the basin.

“It has always been the commission’s position that the Susquehanna River can be a reliable source of water for the city,” said Paul Swartz, SRBC executive director. “But, like all other out-of-basin diversions and large withdrawals, the city had to meet its regulatory obligations so we can protect the basin’s water resources for all users and the environment.”

At its August meeting, the four SRBC commissioners — representing the states of Maryland, Pennsylvania, New York and the federal government — gave unanimous support for the agreement. City officials also indicated their support at the meeting.

Since the 1960s, the city has withdrawn water from the reservoir, known as the Conowingo Pool, intermittently during droughts when the its reservoirs were stressed. The most recent withdrawal occurred in 1999. But the city maintained it had rights which preceded the 1970 establishment of the SRBC to withdraw up to 250 million gallons a day from the reservoir. It never withdrew anywhere near that much, but the SRBC became increasingly concerned about signs that the city might increase its use, especially when it made an agreement to sell 30 million gallons a day to Harford County.

In 1998, the commission took action to block withdrawals without its approval. The city took the commission to court, but a federal judge ruled in favor of SRBC last year. The city appealed the case, but under the new agreement, will drop that appeal.

“This agreement is a plus for both sides,” Swartz said. “It lays to rest, once and for all, the jurisdictional issue and gives the city long-term certainty regarding the availability of water from the Susquehanna River.”

While the Susquehanna is the largest river on the East Coast, there is often barely enough water to go around during low-flows periods in the late summer. The situation is worsened during protracted droughts.

™he Pennsylvania Department of Environmental Protection recently issued a drought watch in much of the river basin because of low rainfall this summer.

Low flows affect the utilities, boaters and others who use the Conowingo Pool, which straddles the Pennsylvania-Maryland border behind the Conowingo Dam, and can result in saltwater seeping into the drinking water supplies at Havre de Grace at the mouth of the river. In addition, low flows threaten the Bay and its resources. Less fresh water flowing down the river means that saltwater stretches farther north, threatening salt-intolerant species of important underwater grass beds in the upper Bay. Low flows in late summer could affect the survival of migratory fish, such as shad, which move downstream at that time. Waterfowl, oysters and other species may be affected as well.

SRBC officials have long said they are responsible for not only ensuring that there is enough water for all users during droughts, but for the Bay as well.

The water supply issue is not isolated to the Susquehanna. Concern has grown in recent years throughout the Bay watershed that growing demand for water could affect habitat and water quality in many rivers, including the Bay itself. The Chesapeake 2000 Agreement acknowledged that concern, calling for the Bay states to “take actions that protect freshwater flow regimes for riverine and estuarine habitats.”