"That should be plenty, given that the total U.S. needs only about 400 billion gallons a day, but the water supply is not uniform around the nation," he noted. "The East is water-rich; the West is water-scarce."

Since 1990, recycled water use increased by 36 percent and is still rising, plus conservation, increased efficiency and productivity, and new technology have helped partially offset the increasing demand for water.

But water needs are expected to increase, especially in areas with the least capacity to handle more, he said.

"As we enter the 21st century, we have tremendous competition between different water users for the same water," Pawlow said.

Because of this, he added, conflicts and disputes over water are cropping up nationwide — even in the traditionally water-rich East.

"Fights about water are in great part about economic development and sustainability," he said.

Pawlow called for more research to find new technology and approaches for water supply and use. And, he said, better planning is needed to assure water quality and supply for the future.

The agriculture and horticulture sectors, he said, likely will be faced with helping maintain water quality by controlling or reducing nutrients in the environment and controlling runoff water from irrigation. He added that increased enforcement or "activism" is expected regarding water and there may be discussion on "federalizing all waters/wet areas in the nation and regulating land use there."

Because of these pending issues, Pawlow said, a federal-state-local partnership might help people work together to find solutions while balancing the country’s "competing economic, population, environmental and other needs for water."