Harry A. Shorter Jr. is carrying on a family tradition his grandfather began in 1920 when he opened Shorter's Place, a restaurant on the Patuxent River in Charles County. There is a major difference, however, in how he's doing it.

William T. ("Capt. Tobe") Shorter caught most of the oysters he served near his restaurant in the Patuxent. His grandson buys oysters from others who have had to go elsewhere for them.

"This used to be one of the major oyster-producing areas in the state of Maryland," Harry Shorter Jr. said the other day. "Years ago, when I was a youngster, the whole damn village depended on it, at least 90 per cent of them anyway. Oysters would always sedimentation down in the river, they get far here. But with pollution and just don't grow like they used to."

Oysters thrive in salty tidewater, and, increasingly, watermen and naturalists say, the river at Benedict has become more fresh and less salty.

It's not the natural fresh water from upriver pushing the tidewater towards the Bay. It's the fresh water discharges from the 54 sewage treatment plants that are located along the 110-mile river that serves not only as a scenic buffer but as a waste disposal drain for the expanding suburbs of Washington and Baltimore.

The scientists speak in their own terminal jargon of "BODs," point and non-point sources and other phrases and words that leave most citizens bored or confused.

But what it all means simply is that as development swallows up more land with more people and congestion, the river dies.

A thick federally-mandated plan that is supposed to keep that from happening is nearing completion amidst charges that it, in effect, both seals the doom of the river and makes possible more development to despoil the land.

It's called the Patuxent River Basin Water Quality Management Plan. It was supposed to be finished in July, 1975, and then, after an extension, last July. Now in its fourth revision, it is under final review before being sent to the federal office in Philadelphia that must approve it.

With federal approval, the Patuxent River sewage treatment agencies will be able to get federal money to plan and build expansions of old plants or new ones to handle the increased waste produced by the growing population upon which the plan is premised.

When that occurs within 25 years, according to the plan, the percentage of fresh water in the river will increase from 46 today to 76 in the year 2000.

"Such increasing quantities of (fresh water) effluent, accompanied by proportionate increases in polluted storm water run-off from the developments generating the effluent," C. Bernard Fowler, president of the Calvert County commissioners, wrote the state last month "will surely destroy the Patuxent River - In general, the plan treats the river as a waste water disposal system . . ."

The pollution of the Potomac River is an accepted fact of life in the Washington area. Among many who live on or near the Patuxent, pollution of that river is an emotional issue that still stirs outrage.

Janice M. Clarke, Patuxent River basin plan manager for the Maryland Water Resources Administration, says it is not her agency's right to use the plan to block expansion of sewage treatment plants. That could be accomplished by refusing to grant discharge permits to agencies to build or expand treatment plants.

"I think we have to realize it's the countries who really determine what growth will be, through zoning and county water and sewer plans," Clarke said. "Our job is simply to make no (sewage treatment) facility a limiting factor," to that growth. "It's not the state's position (it should) control growth."

Last month, Clarke sat through an evening of outspoken opposition to the state's plan It was the required public hearing on the latest revision, held in Upper Marlboro, and her view of her agency's role was not supported by those present.

"Why are we sitting here recommending plant expansion to further pollute the river?" Dent Downing, of Nottingham, wanted to know. "If seems like we always increase the sewage capacity first and then worry about what's happening to the river. It might strike fear into the developers and some of their political friends, but we really should consider a moratorium on development. The first question is always how much sewage capacity will we need by 2000."

Thomes V. Clagett, who lives in Upper Marlboro but owns property on the river, put it more graphically: "Last spring, I put eel pots in the river. When I pulled them out, they looked like they came from a septic tank. You can't bring the fish home because they're full of worms."

"We have to make a living out there," said Bill Hall of the Calvert County Watermen's Association. "Half the stuff you pull out is dead . . . from pollution . . . We're not in favor of adding anything to the river . . . We're not just a bunch of dummies sitting with out heads in the sand anymore. We're out to get anybody who pollutes the river . . . If we have to go to the limits of the law, we'll do that too."

John D. Lehan, a Calvert County waterman, noted the impact of chemical pollution on "the tiniest creature on the river. We're all related to that creature. When we destroy him, we destroy part of ourselves . . . Over my dead body is that Patuxent River going to be degraded," Lehan said. "I been prowling that river for a mighty long time. If you see some fool on the ice during the winter, that's I. I'll do it until I'm 90."

Clarke, the state's Patuxent planner, says it's "furstration over changing plans" that sparks the bitterness. "We're still going to have problems whatever we do. But it's a matter of better alternatives."

The first plan called for a new regional treatment plants instead of more smaller ones. That alternative was scuttled by opposition from Howard County, especially, which plans to expand its plant at Savage, Md. One revision put off all removal of nitrogen pollution - the stuff that eats up the river's oxygen and makes algae grow and other plants and animals die. The latest version, after a complex computer analysis, concluded that phosphorous - not nitrogen - should be kept out of the river.

As required by federal law, a citizens advisory committee on the Patuxent plan was established. It has rarely met and the interest and participation of its members has dropped off. "It's in name only," said Merilyn Reeves, its chairperson from Laurel.

"Years ago," Mrs. Reeves said, "we thought this plan would pull it all together." But state planners working on the Patuxent have come and gone (Clarke has been assigned to the river for only two months) and "if you ask citizens who really don't understant all these complications to remain on a committee for a long period of time, they can't."

Of the panel members, Bill Johnston, a patent lawyer who commutes between Washington and Calvert County, has remained most active, he has mastered the complexities and language of water pollution, prepared technical critiques of the plan and suggested legal action to block it.

The state officials promise to review the criticisms of JOhnston and others, and there may be further revisions or simply more justifications, for the plan as it is. "In the past, we haven't had any plan," said Clarke. "Anything we do at this points is going to be a improvements.

Try telling that to Adolph Welch. He's the only fulltime waterman left in Benedict, and he does most of his oystering in Chesapeake Bay, where salt water remains supreme.

Some weeks ago, for the first time in several years, state health officials opened up the oyster beds across the river in Calvert County. But the river is still closed to oystering here at Benedict and further upriver on the Prince George's County side. Too poluted, officials say.

"It's been rough for me to make it," said the 48-year-old Welch. "I've had to go out on the Bay, every day. It's an awful run . . . This (pollution) stuff had all come on all of a sudden, captain . . . For a long time, we didn't know a damn thing about it".