Deep budget cuts in both Maryland and Virginia could cripple a vaunted effort to clean up the Chesapeake Bay and further hamper the region's campaign to reduce pollution, preserve land and conserve natural resources, officials said yesterday.

Even at current rates of spending, the two states and Pennsylvania will come up $13 billion short of funds they will need by 2010 to meet the cleanup commitments they made two years ago, according to an analysis by the Chesapeake Bay Commission that is expected to be released today.

And Maryland Gov. Parris N. Glendening's latest attempt to advance that effort -- an executive order issued yesterday that requires as much as $1 billion in improvements to sewage treatment plants -- could have little effect without the money to pay for it.

Critics dismissed the new order as an unfunded mandate and a parting shot at Gov.-elect Robert L. Ehrlich Jr. (R), who said during the campaign that sewage plant upgrades would be a top environmental priority.

"After seven years and 10 months in office, he's decided to drop an executive order with a price tag of well more than $1 billion and stick it to the counties," Ehrlich spokesman Paul E. Schurick said of Glendening (D). "It's a political setup. This guy has elevated it to an art form."

Of all the steps the states can take to advance the bay cleanup effort, scientists say that improving sewage treatment plants is one of the most effective. Such efforts, along with requiring farmers to calibrate the amount of fertilizer they apply to fields, could reduce the nitrogen and phosphorous that flow into the bay.

By homing in on sewage plants with new operating restrictions -- without providing money to help install better technology -- Glendening is setting up the effort for failure, or worse, according to one official involved with the cleanup who spoke on the condition of anonymity.

"If you make these announcements . . . and you don't put any money behind it and there's no requirement that the local governments raise money to do it, you lull the public into thinking something is being done," said the official, who noted that Glendening's order is nonbinding and can be reversed by Ehrlich.

Gov. Mark R. Warner (D) has ordered a 15 percent reduction in the budget of Virginia's Natural Resources Department this fiscal year, and more cuts are expected. Glendening has not announced any specific cuts, instead leaving Ehrlich and the legislature to address most of a $600 million deficit in the current year's budget and a nearly $1.2 billion projected shortfall in the following year's.

Even if the states could maintain current levels of funding, they are unlikely to meet their commitment to clean up the bay by 2010, according to a report from the commission.

Already last in the nation in terms of per capita spending on the environment, Virginia has spent the least on the bay cleanup effort so far, according to the commission's analysis, even though it has the largest share of the bay watershed in its boundaries.

And Virginia, whose governor this month became the new chairman of the commission, faces the biggest funding gap in the years ahead. If the state continues current spending patterns, it will commit about $600,000 on bay improvement efforts from 2003 to 2010. But the real cost of reducing pollution from sewage treatment plants, urban runoff and airborne emissions in the state will approach $5.7 billion, according to the commission analysis.

Maryland is expected to funnel about $3.4 billion in federal, state, local and private funds to bay improvement programs between now and 2010, but it still faces a $3.1 billion shortfall, the commission study shows.

"Understanding the price tag should not diminish our drive or our expectations," said Russ Fairchild, a Pennsylvania lawmaker and chairman of the executive council of the bay program. "To accomplish our goals, it is imperative that everyone understands the economic requirements and that we develop strategies to fulfill the commitments needed to restore the bay."

Virginia Natural Resources Secretary W. Tayloe Murphy Jr. said the states' financial difficulties will require them to set priorities for steps to reduce pollution and conserve land.

"It's much easier to prevent degradation than to clean it up," Murphy said.

That is why the states should act now to impose restrictions on sewage treatment plants, which provide a sure fix to the pollution problem, Glendening said.

"This executive order will jump-start Maryland's efforts as we continue to set the pace for the restoration of the Chesapeake Bay," he said at a Kent Island sewage treatment plant.

About 280 treatment plants in the bay watershed do not even attempt to remove nitrogen from their waste streams, even though the pollutant is overwhelmingly responsible for the bay's degradation. Until Maryland's announcement yesterday, none of the jurisdictions required the plants to do so.

Gov. Parris N. Glendening, right, greets charter boat captain Robert Newberry after a news briefing in Stevensville, Md., to urge sewage plant upgrades.