As if the gas shortage weren't enough, an attempt is on to make life even more difficult for the motorist by placing trees, benches, garden plots and other obstacles across streets in residential areas.

Those behind the move say they aim to make life more pleasant for children, pedestrians, and people whho just dislike heavy traffic roaring past their windows.

The idea comes for Holland. Six years ago, the citizens of Delft were the first to step up what they called a "woonerf," which translates roughly as "everybody's backyard." Now there are about 250 all over the country, which is about a third the size of Ohio.

In the wonerf the pedestrian is king. The "streetscape" invites strolling adults and children playing in bunches. To liven it up, the town installs fancy paying, bicycle racks, plants in tubs and in the ground.

Cars are not barred, but they become second-class citizens. Sidewalk may be eliminated to emphasize that people are free to walk anywhere. Drivers must keep to 20 miles an hours and watch out for speed bumps, chains, sharp bends, patches of cobblestones and concrete barriers. Parking is allowed only in clearly defined areas, and through traffic is banned.

The Council for International Urban Liaison in Washington says the plan has spread to Britain, Belgium, West Germany and the Scandinavian countries and is ripe for introduction to the United States. Its communications director, an ex-diplomat names George G. Wynne, says:

"If we can have pedestrian zones in business areas, we certainly ought to be able to calm down the traffic in places where people live".

He quotes Dutch city authorities as calculating that a "woonerf" costs only about 50 percemt more than just resurfacing a street, which has to be done from time to time anyway. It also raised property values, not to mention tax assessments, and the claim is made that it has stopped the rot in some poorer areas that were getting close to being slums.

Wynne takes pride in his organization's record of getting U.S. cities to adopt ideas from other countries. The June issue of his publication "Urban Innovation Aboard" lists some recent ones:

Two U.S. cities -- Albany, N.Y., and Akron, Ohio -- have ordered a Swiss compound called "Verglimit" that it mixed with paving material to raise its temperature in the winter and keep ice from forming on bridges and overpasses.

Cities in California and Montana as well as the District of Columbia are experimenting with a Japanese system for making traffic lights audible to help the blind cross streets safety. A firm in California is now making a device that plays a birdcall when the green light comes on which automatically grows louder as the traffic grows heavier.

About 50 swimming pools with hydraulically-controlled floors, poineered in West Germany, are now being built or already in use in the United States and Canada. The bottom can be raise or lowered at the touch of a button, so that the pool can be used at some hours by children or the handicapped, and at others by experienced. swimmers and divers.

Some ideas from outside do less well A system of ticket-books for motorists, designed to replace the parking meter, orginated in Tel Aviv and has made progress in places as far apart as Amsterdam and Sydney. But so far it has found no takers in the United States.

And Wynne has written a saga he calls "The Return of Birdsill Holly," about an Amerian inventor of that name who originated a system for heating a whole set of buildings from a single source nearly 100 years ago. CAPTION: Picture, Moderate-income neighborhood in Delft, Holland, before and after building of the "woonerf," which means "everybody's backyard." AP