Next week, turning on the faucet, shower or dishwasher could begin to have new implications for the Connecticut homes and businesses with public water supplies and the private and municipal companies that provide it.

On Tuesday, the General Assembly's Regulation Review Committee is scheduled to vote on final approval of the first comprehensive state regulations to govern how much water suppliers must release into rivers and streams from their reservoirs. It will apply to owners of dams that impound public drinking water supplies, but not to hydroelectric dams. These are already regulated for flow levels by federal and state licenses.

Perhaps most important, the regulations establish minimum base flows that no river is permitted to fall below, and set up a system of variable releases throughout the year designed to mimic the natural seasonal highs and lows, said Betsey Wingfield, bureau chief of DEEP's Bureau of Water Protection and Land Reuse. This is considered better for river habitats than setting a single minimum flow, because it means riverbanks would be watered at critical times of year for important plant and animal species, and enough water would be in streams to form pools when aquatic creatures are laying eggs and hatching.

"It's not just about fish. It's about the wetlands and natural flood systems," said Mark P. Smith, deputy director of The Nature Conservancy's Freshwater Program, who has worked with Connecticut and other New England States on streamflow issues. "Varying flows and water levels are really what drives nature. It's what nature has evolved around. When you take those away through dams, it's a cascading effect. These regulations are about striking a balance - how much can we mimic the natural cycles and still meet our own needs?"

The Regulation Review Committee has rejected two earlier versions of the streamflow rules, and a third earlier version was withdrawn by the state Department of Energy and Environmental Protection before it came to a committee vote.

The streamflow regulations are a recognition that water quality and the health of rivers and surrounding habitat depend on enough water flowing at the right times of year. Key quality measures such as dissolved oxygen and temperature, which can make the difference between a habitat that can support aquatic animals and one that can't, are very sensitive to the water quantity. And states, as the stewards of their waters made responsible for maintaining and working to improve water quality under the federal Clean Water Act, are looking to flow issues as a means of meeting that responsibility.

"States are allowed to protect their waters, and have the authority to regulate flows," said Robert Abele, instream flow coordinator for the New England regional office of the Environmental Protection Agency. "All the New England states are in one way or another looking at regulating streamflows."

Tuesday's will be the committee's second vote on the regulations - the first vote in 2010 rejected an earlier version of the regulations with broader requirements that would have applied to more water users. The regulations were crafted to implement a measure approved by the state legislature and signed into law by former Gov. M. Jodi Rell in 2005.

"We've signed off on them," said Elizabeth Gara, executive director of the Connecticut Water Works Association, which represents private and municipal water companies. "It took a long time to achieve the balance the legislature sought in the 2005 law, but the negotiations we've had were helpful in addressing our major concerns."

The lead agency in writing the regulations, the DEEP, has been at it for six years, holding public hearings, meeting with water company and environmental groups to reach compromises that balance human water needs with those of rivers and stream ecosystems, said Wingfield.

"This is very, very important," said Karl Wagener, executive director of the Connecticut Council on Environmental Quality, a state agency charged with identifying statewide environmental problems that has supported adoption of the regulations. "You probably don't notice it much during years of good rainfall, but there are streams in the state that get to the point where most of the flows in them are from discharges of treated wastewater. If this were allowed to continue, we'd see it (unnaturally low flows) more and more."

Among other changes from the 2010 version, the proposed regulations no longer apply to groundwater withdrawals - a particularly difficult sticking point for municipal and private water companies that rely on wells - and exempt small reservoirs and water withdrawals for agriculture. Golf courses that water their greens from nearby streams are also exempt, provided they follow efficiency and conservation practices for water use, landscaping and other areas.

"We compromised on many points," said Margaret Miner, executive director of the Rivers Alliance of Connecticut and one of environmental group representatives who participated in the regulation negotiations. "But the public will notice a difference once these are in place. Streams won't be just bone dry in the summer, and the water will be colder, and moving better. There will be more fish, and people will be able to canoe more times of the year. We're trying to establish healthy river habitats with these flows."

The latest version gives water companies 10 years to make the infrastructure improvements to dams and spillways that will be needed to make the required releases, with provisions for extending the deadline if needed. Additionally, it makes allowances for water companies to withdraw enough to continue meeting "safe yield" amounts during droughts by releasing less water downstream than would otherwise be considered environmentally healthy.

A water company at risk of falling below the "safe yield," which is 15 percent above its highest expected demand, could be granted permission to release less water than required, provided it demonstrated it had conservation measures in place and had a long-range plan for developing new water sources, Wingfield said.

Water companies also won what they consider a critical guarantee in the proposed regulations that rivers and streams that supply their reservoirs would not be put into either of the two most restrictive classifications. There are four classifications all rivers and streams in the state would fall under, each with different flow release requirements.

"There are a lot of exemptions built into the regulations," said Lynn Werner, who participated in the regulation negotiations in her role as executive director of the Housatonic Valley Association, which represents a 2,000-square-mile watershed in northwestern Connecticut, Massachusetts and New York state. "They are a flexible response to the needs of water utilities and to the biological needs of streams. This doesn't mean there will be natural flows in streams at the expense of drinking water. But this does put the environment on the table with other uses of water, and acknowledges that healthy rivers have value to society."

Gara, of the waterworks association, said 60 reservoirs in the state will be subject to the new water release rules. About 80 others are exempt because of their small size, and another 42 are inactive.

"There will be costs associated with modifying the dams to make these releases," she said. "There will be rate increases associated with this."

Bruce Silverstone, vice president of corporate communications for Aquarion Water Co., which serves customers in Mystic, Stonington and many other communities throughout the state, called the proposed regulations "a reasonable midpoint."

Most significantly for local Aquarion customers, Silverstone said the regulations will mean that the Mystic reservoir system will be required to release more water into Copps Brook than it currently does. That, in turn, could mean rate increases to cover the costs of infrastructure improvements.

"There will in fact be reductions in our water supply," he said. "We've already begin a search for additional supply. But we have 10 years, so we have plenty of time to do this."

Groton Utilities, which provides water to about 40,000 customers from its reservoir system, has for the past two years been operating as though the streamflow regulations were already in place. Rick Stevens, general manager of the water and wastewater division, said that over the past two years, the utility has been carefully managing the timing and amount of releases into Great Brook and testing the water quality to ensure it can maintain a healthy aquatic habitat. The program was done in cooperation with DEEP, as a condition of a permit the utility was recently granted.

The Groton project serves as an example of how a water company can successfully manage its flows under the new regulations, said Rob Hust, assistant director of planning and standards at DEEP's Bureau of Water Protection and Land Reuse. The regulations are written so that flow requirements will be developed for the unique conditions of each river or stream, he noted.

"What we learned is that by managing water in a holistic manner the way Groton has, there are ways of meeting supply needs and protecting stream flow and environmental resources," Hust said in an email.

Until the 2005 law, the state regulated water releases for only two categories of rivers and streams. Since 1979, owners of dams on the 5 percent of rivers and streams stocked with fish had to release sufficient water downstream of their reservoirs to ensure that trout and other species popular with anglers could survive and spawn. Then in 1982, the Water Diversion Act was adopted, but it set minimum flows for only the 16 percent of new water diverters and dam owners that obtained the newly required permits after the law was enacted.

Existing users, including the state's largest water companies, were exempted under a grandfather clause, and required only to register with the state. That meant water companies could legally withhold so much water that a stream below a reservoir could be left to run dry.

That did, in fact, happen at least twice in the recent past, on the Shepaug River in the state's northwest corner, and on the Fenton River near the University of Connecticut's main campus. Both cases are often cited as important catalysts in bringing the issue of adequate water flows and the lack of controls to the state's attention.

"We have seen rivers go completely dry here in Connecticut," said Dixie Goodwin of Ledyard, president of the Thames Valley Chapter of Trout Unlimited, one of several fishing groups that support adoption of the streamflow regulations. "What we're asking is that enough water be left in rivers and streams so that wildlife can survive. That hasn't happened. There are a lot of compromises in the regulations. We really hope they haven't compromised too much."

In a 2010 DEEP report, about two dozen streams or segments of rivers are listed with "impaired" water quality due to low flows from excessive withdrawals. But the list is not comprehensive, according to Hust at DEEP, and by some estimates, there are as many as 60 rivers and streams with harmfully low flows. The report is submitted annually to the federal EPA as part of the state's Clean Water Act responsibilities.

One weakness of the proposed regulations, according to environmental advocates, is the groundwater exemption, because groundwater wells are often hydrologically connected to a river's base flow. Excessive pumping of groundwater wells by UConn was, in fact, the reason the Fenton River ran dry in 2005, resulting in a major fishkill.

Since then, UConn has lowered its demand on the Fenton by drawing more of its water from the larger Willimantic River watershed, and implemented water conservation and system upgrades. It repaired leaks, stopped reservoir spillage, improved equipment, installed water-saving showers and faucets in dormitories and curtailed water use when drought conditions threatened, said Rich Miller, UConn's director of environmental policy.

"We reduced our consumption by 100,000 gallons a day, mostly from the supply side," he said. "Before 2005, we were not routinely repairing leaks or replacing pipes, and we had a 70- to 100-year-old system. Now we do regular inspections."

To Meg Reich, vice president of the Willimantic River Alliance, the Fenton River story provides an important example to the rest of the state. The problems aren't with supply, she said, so much as with waste, poor management and lack of conservation.

"The reality now is that UConn has been operating successfully now for six years. It's been a shining example, after this environmental disaster," she said.

Her message to water companies: "Just do it. Notify customers they need to conserve water, and live with it and see how it works. They may need to create more storage capacity. But the bottom line is that it's worked well here, and this is a proven example."

Anthony Irving, chairman of the Eightmile River Wild & Scenic Coordinating Committee, is among those who lament that groundwater withdrawals were written out of the regulations, and remain unregulated. The Eightmile River his group works to protect, in Salem, Lyme and East Haddam, is not under threat from future surface withdrawals for public water supply, he said. But he can foresee a public wellfield being dug that could overtax the Eightmile's base flow.

"That could be an issue for us down the road," he said. To those who say groundwater regulation can wait for a future revision, he answers: "This was the time to do it. It wasn't for another day."

j.benson@theday.com

Proposed streamflow regulations

• Apply to all state's rivers and streams.

• Apply to all dams that impound or divert rivers or streams.

• Each river or stream would be designated as Class I, II, III or IV.

• Class I is the most restrictive; natural free flowing conditions would be maintained.

• Class II are "minimally impacted." Dam owners on these waterways would be required to release 75 percent or more of the stream's natural flow, with variations according to season.

• Class III streams are "moderately altered." Releases would vary throughout the year to mimic natural cycles. U.S. Geological Survey data from free-flowing streams in the state would be used to extrapolate flow requirements for each Class III stream; watershed size would also be factored in.

• Class IV streams are considered "substantially altered," with water release requirements tailored to meet human needs first. After those are met, the goal is to achieve "the best streamflow that can be achieved," with releases following the variable levels similar to Class III as much as possible.

• Stream classifications for each waterway would be proposed by DEEP, a map pubished and a public notice issued. After a 90-day public comment period, DEEP, in consultation with the departments of Public Health, Economic and Community Development and Agriculture, and the Office of Policy and Management, would consider the comments and decide on classifications.

• Water companies would have 10 years to make improvements to dams and other equipment to meet the new flow requirements.

• Special provisions for droughts allowing for reduced water releases are included.

Source: Connecticut Department of Energy and Environmental Protection