The illustration from Kenneth Grahame's 1907 classic, "Wind in the Willows" has been reprinted countless times -- Rat and Mole on an idyll along the riverbank in an old wooden rowboat:

"Believe me my young friend," murmurs Rattie, "there is nothing -- absolutely nothing -- half so much worth doing as simply messing about in boats."

Now fast forward to 1994, a time when "messing about in boats" is a more pleasurable escape than ever from an increasingly crowded, hectic life on the land.

But Rat has to shout to be heard now, because he and Mole are making at 30 knots, fur plastered back by the rush of wind across their sleek, Fiberglas cruiser.

Like as not they are packing the latest in boron-graphite composite fishing rods, global positioning satellite navigation devices, and fish locaters that can count the scales on a rockfish at the bottom of the bay's ship channel.

And our modern Rat and Mole, being environmentally savvy vermin, know that messing about is getting more complicated these days, as we realize all the ways even good clean fun can have its downside:

* Maryland and Virginia are struggling to stop the discharge of sewage from recreational boats that inhabit the summertime bay in concentrations approaching the population of small cities.

* Dredging and bulkheading to meet the demand for more marina space is a concern. So is the potential for runoff of toxic paints and chemicals from boat work and cleaning.

* Thousands of tons of aging Fiberglas hulls are not currently recyclable -- and there is little market for the earliest generations of them from the 1960s and 1970s.

* Fast boats and modern electronics have made even casual fishermen far more capable of putting too much pressure on nearly all varieties of sport fish.

* The EPA is proposing to ban lead in fishing sinkers, which have been implicated in poisoning swans and loons that swallow them.

* Concern is growing about all the monofilament fishing line and other plastic that is thrown overboard, snagging wildlife and blocking the digestive tracts of fish and turtles.

But the aspect of modern messing about in boats that is under the most scrutiny -- with sure implications for some 120,000 Marylanders who own them -- is the outboard motor.

Rat and Mole in our Chesapeake scenario are running twin 235 horsepower models, with enough speed in reserve to make a race of it with some slower airplanes.

Like almost all outboards, theirs are two-stroke, or two-cycle engines, which develop incredible power from relatively little weight, compared with the four-stroke engines in cars.

Since childhood, I have been among the outboard motor's devotees, owning engines from two to 200 horses.

Even in our car culture, with highways to anywhere, there is nothing so liberating as heading out into the quickening dawn in a boat, your wake essaying the first passage of the day on the gleaming, limitless bay.

In one halcyon three-year period I traveled close to 20,000 miles on the bay in outboards, and the experience never dulled.

So like most boaters, I have been dismayed to hear from the EPA that the average two stroke, running for about 20 miles, produces as much pollution as a car driven 800 miles.

The same two stroke that saves crucial weight over automotive technology, also exhausts far larger quantities of unburned fuel, according to Ken Zerafa, an EPA expert on outboard emissions.

Another way to think of it is this: For every gallon of oil you mix with your outboard's gasoline, about a quart is pushed out of the exhaust, just as if you were dumping it into the bay.

By Oct. 1, the EPA, which says it has had excellent cooperation from the marine industry, will propose regulations to reduce polluting hydrocarbons 70 percent to 80 percent from outboards in the next decade or so.

"It will basically mean retooling the entire outboard industry," Zerafa says.

Industry technical experts like Don Schultz of Mercury Marine in Oshkosk, Wis., say that his company and others are even now coming to market with new models of four-stroke outboards.

These will be vastly quieter, smoke-free engines -- also somewhat more expensive, heavier and containing more moving parts than the old two-strokes.

Honda, a relatively small seller of outboards in America, already sells a line of four strokes, from two to 45 horsepower.

Larger outboards -- 100 horsepower and up -- will likely have to stay with two-stroke technology because of weight considerations. Computer chips, direct fuel injection and other technologies will make them environmentally more benign.

Fuel efficiency should increase, though pushing a boat through water is doomed to be more consumptive of gas than cars -- 5 or 6 miles per gallon down to around one mile per gallon is the current range for outboard driven boats.

Meanwhile, what can the average boater do to minimize his outboard's impact?

I asked John Page Williams of the Chesapeake Bay Foundation. He is by nature and profession an environmentalist, author of "Exploring the Chesapeake in Small Boats," and owner of a 17-foot boat with a 90 horsepower outboard.

He swears by the biodegradable engine oil he has been using for more than a year -- available through most major outboard dealers, though you may have to ask for it. It is nearly three times as expensive as regular oil, Williams says; but for the 100 hours he runs a year, which is twice what the average outboard owner runs, his added cost is a mere $60.

Perhaps the biggest change available to the many outboarders who trailer their boats is to use the bay region's abundance of launching ramps wisely, to cut running time.

"Your tow vehicle is far less polluting then your outboard," Williams says. "By all means use your boat and have fun, but by taking advantage of ramps you can spend more time fishing and save on fuel."

Also, anything a boater can do to save fuel, from choosing the correct propeller to keeping the engine tuned, will cut pollution. Biodegradable boat cleansers are also available now.

Admittedly, no one boater can make a big difference. Even outboards as a class are small polluters compared with cars, sewage plants and agriculture.

But taking personal responsibility for minimizing your environmental impact in any area has a way of spreading to other areas of one's life. And as population and leisure time grow, and existing laws wring the remaining easy pollution from cars and factories, "secondary" sources like outboards grow in importance.

Boaters who want to mess about with less mess can also write the Chesapeake Bay Foundation in Annapolis for its guide: "Your Boat and the Bay."

Jobs and environment

An important point was omitted from last week's column, which took to task gubernatorial candidates who raise the specter of jobs vs. environmental protection.

Anyone who thinks such an either-or position is inevitable ought to look at Maryland Republican Congressman Wayne Gilchrest.

He has an exemplary environmental rating from conservation groups -- 95 percent in 1993; and in the latest ratings available, he got a solid 83 percent rating from national business organizations.