On one side of 31st Street in Ocean City, just where the road comes to a deadend at the edge of the Atlantic Ocean, there are 18 $80,000 town houses, and in the summertime, no beach.

Across the way is the eight-story Sea Gate condominium complex, an 83-unit project built by three prominent Ocean City developers. Spread out in front of it during the summer months is a beautiful sandy beach.

As far as the town house owners are concerned, that beach belongs to them. And they want it back.

The battle of the beach started three years ago, when a 200-foot wooden jetty was built, sticking out into the ocean between the old townhouses and the new condominiums.

The idea of the jetty - a thin wooden, structure that stretches out into the ocean perpendicular to the beach - was to distribute the beach sand between the twon houses, which had plenty, and the condominiums, which had none.

The practical effect, however, was somewhat different. Instead of creathing beaches in front of bothe developments, the jetty has simply moved the town house beach south, in front of the condominiums, leaving only dangerous water and marshes behind.

The town house owners left behind in the marshes - a group that includes prominent lawyers, a former Prince George's judge and a CIA official, - have very simple feelings about the situation.

"They moved our beach in front of the high rise and we want it back," said William McLaughlin, a town house owner. "If we have to sue the mayor to get it back, we will."

The town house owners are angry at Ocean City Mayor Harry W. Kelley because, they contend, he asked the state to build the jetty to redistribute the beach. "He said if the thing didn't work he would take it down," said Frank Aluisi, a former Prince George's County commissioner who owns one of the townhouses and is also serving as the attorney for the town house owners.

"But we've met with him and he says the mayor should do it. We've just been put on a yo-yo."

Basically, Aluisi says, it's a matter of what nature wants.

"The fact is that we had a beach three years ago and they built a jetty and now we don't have one," Aluisi said. "I don't think it was the intention of nature to have a beach on one side and no beach on the other."

Not surprisingly, the condominiums' developers, Charles Disharron, James English, and Richard Layfield, are perfectly content with the situation the way it is.

"The sad thing is that those people can really raise a lot of hell," Disharoon said yesterday. "I don't think the jetty should come down and the mayor agreed with me earlier this summer that that wasn't the answer.But these people can apply a lot of pressure."

Disharoon said that the jetty was built by the state's Department of Natural Resources at the request of Kelley, who had been approached by the developers about a lack of beach in front of their property.

According to Leonard Larese-Casanova, director of the shore erosion control program of the state Department of Natural Resources, the project was funded by the state. But the funds, he said, came from an allocation marked for Ocean City, which is usually used for projects that the city requests.

The petty, which rises as high as 14 feet above the beach and 2 feet above the water at low tide, was lowered by 2 feet a year ago in an attempt to solve the problem, Casanova said.

But the attempt didn't work. Now, Casanova said the Natural Resources Department must wait for a request from Kelley for the Ocean City Council before funds are used to tear the jetty down.