Caught in a federal-state funding standoff that one Delaware official said could put lives at risk, widely used public tide and weather monitors at more than 10 Delaware River and Bay sites face shutdown by September.

The National Oceanic and Atmospheric Administration posted the shutdown notice with little fanfare for its local Physical Oceanographic Real-Time System (PORTS) sites. Few outside of river and bay maritime interests were aware of the threat on Thursday.

The data, available to the public around the clock, has become an essential tool for commercial shipping, boaters and fishing interests, researchers. The information also has become important more recently to coastal communities and residents increasingly threatened by severe storms and flooding, and the threat of much worse under most scenarios for global warming and climate change.

“I know that ship captains depend on this data as well as residents,” said Gerald J. Kauffman, Water Resources Agency director at the University of Delaware. “We’ve heard from school districts that watch these sites and re-route school buses because of high tides.

“Anybody who uses this information values it. It can mean lives. I’m against shutting it down,” he said.

Pennsylvania had been paying maintenance costs, but cut its funding by 50 percent in 2011 and ended the allocation entirely in 2012. NOAA manages the sites, but doesn’t cover that spending.

NOAA officials, who fall under the Department of Commerce, say the agency will try to operate the rest of the network until Sept. 1 while a search for maintenance money continues. They say, however, breakdowns will not be repaired during that time, and a full shutdown and removal of the monitors will follow.

“The New York/New Jersey PORTS will likely be in the same situation as of the end of March,” said Keeley Belva, spokeswoman for NOAA’s National Ocean Service. “The Port Authority of New York/New Jersey is actively pursuing funding to avoid a shutdown.

“The NOAA partner of a small PORTS in New Haven, Conn., is also actively pursuing funding to avoid a shutdown,” she added.

Belva said the Delaware system halted temporarily in 2004 after the Maritime Exchange for the Delaware River and Bay stopped paying for the upkeep. It resumed in 2005 when Pennsylvania picked up the cost through the Philadelphia Regional Port Authority.

Collin P. O’Mara, secretary of the Delaware Department of Natural Resources and Environmental Control, said he had learned of the funding and network problems only Thursday, and planned to look into the issue quickly. He said that he was unaware of the Pennsylvania port agency’s decision to stop financing the program.

“The network does provide critical data for the region,” O’Mara said.

NOAA oversees similar networks at 20 other port complexes nationwide, with some, including the ports of New York and New Jersey, under a similar short-term threat. One operation in Gulfport, Miss., shut down last year.

The Delaware Bay operation, with 14 installations, stretches from the just south of Trenton, N.J., to the mouth of the bay at Lewes and Cape May. N.J.

Although some sites have a wider array of capabilities, most at least monitor changing water, wind and temperature levels. Some also provide other data like currents and barometric pressure.

Maintenance nationwide costs about $5 million, but has been made the responsibility of states or other local sponsors. Delaware’s share was estimated at $300,000 yearly and the Chesapeake Bay system around Baltimore costs about $500,000, officials said.

During Superstorm Sandy, Kelvin Ramsey with the Delaware Geological Survey was stationed at the Delaware Emergency Management Agency. His key tool in monitoring the storm: the network of tide gauges along the Delaware estuary.

“That was one of my primary resources,” Ramsey said, adding that he was unaware they might be terminated.

Because the water-level readings are updated every six minutes, it gives scientists like Ramsey a good indication of how a storm is progressing.

Coastal residents like Jim Bailey, at Broadkill Beach, complained recently about the lack of available data on tides and anything that could be used to monitor changes in sea-level rise. He urged state officials to come up with a better monitoring system.

As it now stands, there are the tide gauges and the Delaware Department of Transportation has a new mobile phone app that can access traffic cameras. During the most recent northeast storm, state officials moved mobile cameras to Prime Hook and Broadkill Beach roads.

Prime Hook resident Richard Allan used the mobile app to monitor road conditions long after the storm had passed but flood conditions in his area continued.

One station, the Brandywine Shoal Lighthouse site, already has gone offline after being damaged by Superstorm Sandy’s waves in late October. Federal officials have said that repairs will await a decision on local funding.

Only the Lewes, Cape May and Atlantic City, N.J., sites would continue under a separate federal program, along with a Reedy Point station at the mouth of the Chesapeake & Delaware Canal.

Dennis Rochford, president of the Maritime Exchange, said he and Lucy Ambrosino, outreach manager for the Port of New York/New Jersey, are encouraging all regions of the country with PORTS sites to seek full federal maintenance funding.

A draft letter provided to other port directors called the federal government’s failure to provide full upkeep “astonishing,” and described the stations as the “single most important components of our regional maritime infrastructure.”

“Pennsylvania was paying for the maintenance of the system, which benefits basically all three states, the entire Delaware [River] from Trenton to the sea,” Rochford said. “This is a significant, significant issue on the Delaware River with respect to navigation, and the dollar amount does not seem to be all that significant.”

Delaware City relies heavily on the system when storms threaten. Partial evacuations have been ordered twice in recent years, City Manager Richard Cathcart said, and the PORTS readings helped to determine timing and preparations.

“That’s bad news for us,” Cathcart said. “We rely on them.”