Post cards from the Ohio River Valley. Once the route west for American pioneers, this is now a quiet, homey region

On a hazy summer afternoon the Ohio River seems to flow as slowly as time itself through the little towns along the water's edge. It was during the late 18th and early 19th centuries that these towns were established, after the Northwest Territories were opened up for settlement. The Ohio was a main route out to the Plains states, and the valley's glory days came when steamboats plied the river, carrying settlers westward.

More or less westward, that is. It is in the nature of rivers to bend and twist and change their minds about just which way to flow. And it is in the nature of railroads to go exactly where the railroad builders want them to go.

In a short time, the straighter, faster, more reliable railroads took the place of the steamboats, and the river towns were left without much of an economic raison d'^etre. And yet the region has a certain fascination for a visitor inured to interchangeable shopping malls and fast-food strips, and the same identical white-on-green offramp signs from one coast to another.

This is porch-swing country. This is the kind of place where the filling stations sell mostly regional brands of gas. The towns here usually are too small to attract national franchisers, so this is the home of little diners instead. And of lots of auto parts dealers -- people here fix 'em up instead of buying new ones -- and of ``nite crawlers for sale.''

More appetizingly, perhaps, it's also the home of soft ice-cream shops -- squat white buildings where the clerk talks to you through a little window that opens sideways.

A visitor can feel like a time traveler back on Main Street of Hometown, USA. Still, the people who live here have to make a living. And it's not been easy.

Close to the river, the land is too hilly to be good for more than subsistence farming. Some people joke that what keeps this part of Ohio going is the state highway department: ``There's highways there, and somebody's gotta keep 'em maintained,'' as one Ohio expert puts it.

Time was when the little town of Moscow and its environs pinned their hopes on the Zimmer Nuclear Power Plant, whose cooling tower looms over the village. But last summer, when the plant was 97 percent finished, the three utilities that own it announced it would never operate as a nuclear plant, as a result of cost problems and licensing difficulties.

There are plans to convert the Zimmer plant to coal -- which will mean lots of construction jobs when the project heats back up again. But that won't be until early 1987, even if discussions on how the utilities will recover their costs from the nuclear project go smoothly.

The story over in Pike County is of the boom that got away. Pike County is where the US Department of Energy sank $2.6 billion into a gas centrifuge enrichment plant (GCEP) and then changed its mind about the project. The GCEP would have been a energy-efficient means of preparing uranium for nuclear reactors; it was under construction adjacent to an existing gas diffusion plant, which for 30 years has been a major employer in Pike County. But on June 5, the Department of Energy announced its intention t o ``terminate'' the project and to pursue an even more energy-efficient enrichment process involving lasers.

Further upland, in more prosperous farm country, runs the Appalachian Highway, built to spur economic development in the region.

Over toward Batavia, the blue-and-white logo of an enormous Ford transmission plant, looming over the highway like a mirage, is evidence of success. The plant hasn't provided as much employment as originally planned, however, and many of the jobs were not new ones, but jobs moved from other Ford operations closer to Cincinnati.

A happier tale is to be told over in Portsmouth, however. This town, once a regional center for steel, shoes, transportation, and other industries, has lost much of that base, and the town has a high unemployment rate.

But one local entrepreneur has built up a new industry: waterbed manufacturing. A local furniture store dealer noticed that waterbeds were popular with his customers and wondered whether they couldn't be made locally instead of being shipped in from California.

``We opened our factory in November 1981 and shipped our first product in January of 1982,'' says Edward Levi, president of JWL Inc. ``Now we ship from Holton, Maine, to Florida.'' Employment at JWL has gone from 13 people at the beginning to more than 100 today, and Mr. Levi expects it to reach 150 by the first of the year, after a plant expansion. He's had help from a low-interest loan from state development officials, and backing from local banks as well.

``The future of Ohio is in small industry -- diversified industry -- so we don't have all the peaks and valleys we've had before,'' Mr. Levi says. ``It's also important to have local people investing in putting people to work.''

Those expectations seem as modest and sensible as the little towns themselves that dot this valley.