March 28, 1982

THE Connecticut River appears to be the dividing line for outbreaks of gypsy moth caterpillars this year. According to state entomologists, residents east of the river can expect the worst, while those who live west of the river and got the brunt of last year's defoliation will see less of it. These predictions are based on ongoing counts of the buff-colored egg masses that were laid by female moths last August. The eggs can be found on tree trunks, fence posts, stone walls, garbage cans and house shingles. Professional entomologists are still out in forests and woodlands completing egg counts. Dr. John F. Anderson, the State Entomologist and the head of the Department of Entomology at the Connecticut Agricultural Experiment Station in New Haven, said they had found a lot of egg masses east of the Connecticut River.

AFEW years ago, when most families were spending 25 percent of t heir incomes on their homes, they had the other 75 percent to c ushion unexpected house expenses. If real estate taxes went up, theyb ought fewer clothes; if utilities went up, they cut theater-going a nd restaurants. Now, when it costs so much more to buy and run a house, most families are spending 30 to 35 percent of their incomes on their homes, some are spending well over 40 percent, and the cushion is much thinner. When such families are hit by unexpected housing costs, they have to cut spending on necessities, not just frills or luxuries, and the adjustments can be painful.

ALBANY THE Suffolk County law requiring a 5-cent deposit on all beverage containers is scheduled to take effect on Thursday, amid a cloud of confusion and uncertainty that has prolonged, if not intensified, the already fierce debate surrounding it. The state is considering action that would gut a major portion of the deposit law, beverage industry officials are seeking a court injunction to block the carrying out of the law and the Legislature is considering various antilitter proposals, including one that would nullify the Suffolk law. The industry asserts that the law is ''vague'' and that the packaging of alcohol beverages is pre-empted from local control by the State Alcohol Beverage Control Act. A hearing on the case has been scheduled for tomorrow in State Supreme Court in Riverhead. Industry officials have asked that enactment of the law be delayed pending the outcome of that hearing.

THE ripple effect from last week's dumping of sludge spoil in Long Island Sound within two miles of Lloyd Neck has spilled over into the Island's political arena. Despite efforts by the Republican Representatives from the North Shore to stop the Army Corps of Engineers from permitting the dumping, Democratic officials in the Town of Huntington and in Suffolk County asserted that the delegation did not try hard enough. ''It's very clear to me that they did not do a thing,'' said Robert J. Mrazek, Democrat of Centerport, who is the minority leader of the Suffolk County Legislature and a potential candidate for a House race on the North Shore. Although the Congressmen sent letters to the White House and to Interior Secretary James G. Watt protesting the Army engineers' action, Mr. Mrazek said that ''sending a letter does not make up for the hard work needed to stop this thing cold.''

DUTCH SHEA, JR. By John Gregory Dunne. 352 pp. New York: The Linden Press/Simon & Shuster. $15.95. JOHN GREGORY DUNNE, reporter, essayist, novelist, scriptwriter, wry observer of California mores, is best known for two of his five earlier books. ''Vegas'' (1974) is a partially fictive memoir of a dark night of the soul spent in appropriate surroundings. ''True Confessions'' (1977) is a grand novel (as one of Mr. Dunne's professional Irishmen might say) and a grand movie, the script for which was written by Mr. Dunne and his wife, Joan Didion. If you liked these earlier books, you will like ''Dutch Shea, Jr.'' For one thing, the heroes of all three books are ''people without illusions'' -except for the illusion that they are without them.