Connecticut, it might seem, has plenty of water.

But its more than 6,000 miles of rivers and streams, along with the groundwater supplies, lakes and ponds that make up the state's abundant freshwater resources aren't being managed and protected the way they should be - or at least that's the premise behind proposed new regulations.

Called stream flow regulations, they were written by the state Department of Environmental Protection in consultation with scientists, fisheries experts and representatives of environmental groups, farmers and private and municipal water companies to comply with a new state law.

That law grew out of a 2002 state Supreme Court case involving water rights in the western part of the state, said Betsy Wingfield, chief of the DEP's water protection and land reuse bureau.

"Our current regulations have no basis in science for what is healthy for streams," she said.

The new regulations, if adopted, would for the first time establish comprehensive standards for how much water can be taken from and emptied into water sources tapped for drinking and businesses, Wingfield said, using a four-tier classification system of each source's ecological condition and human use.

Dams, municipal and private water company supplies would be affected. Previously, the state's rivers and streams were only regulated for fish-stocking purposes, she added.

The overall purpose of the regulations, Wingfield said, is to strike a balance between the needs of humans and those of wildlife, so that streams, rivers, lakes and ponds maintain water levels that can support healthy ecosystems, while people can still have adequate water supplies.

The regulations, she said, would encourage more regional, cooperative approaches to meeting water needs, and would be phased in over several years.

Mark P. Smith, director of the Nature Conservancy's freshwater program for the eastern United States, was among those on the advisory panel that developed the regulations.

The new regulations, he said, reflect "a very thoughtful understanding of water systems and trying to apply that in a way that's workable."

"All rivers will benefit," he said. "This provides a framework for where (water companies) can look for water, and which ones need more protection."

"Water is not only key to the environment but also to the economy," he added, and the new rules establish the mechanism for sustainable water use for both.

But others are concerned the regulations as written go too far, and are pushing for changes before they're adopted.

"We understand the need for extending flow regulations to all rivers and streams," said Elizabeth Gara, executive director of the Connecticut Water Works Association, which represents most of the state's municipal and private water companies. "But it's something the state needs to be careful about."

She, too, is looking for rules that strike a balance, but believes that in their present form, the balance is tipped too heavily toward ecosystem protection at the expense of human needs. Restrictions on water withdrawals that would be imposed by the regulations, she said, would impact economic development, quality of life and public health and safety.

"They would leave us without adequate safe yield to meet the needs of our customers," she said, "and force infrastructure upgrades that will cost ratepayers millions. We may have to change pipes and intake valves and develop some new sources of supplies" to keep existing sources at minimum levels.

Among local officials opposed to the current version of the regulations is Barry Weiner, chairman of the New London Water and Water Pollution Control Authority. The New London water system, which supplies customers in New London, Waterford and parts of Montville, taps Lake Konomoc in Waterford for its main source, in addition to several smaller lakes and ponds.

"We would potentially have to stop taking water from certain supplies and do downstream releases," Weiner said. "This could be a serious obstacle for municipal water systems and ultimately it will fall on ratepayers."