The sewer lines finally are in and new roads have been built on top of them. And sometime in mid-May, the 1799 town of Haymarket will enter the 20th century.

Sewers will mean an end to decades of polluted wells, outhouses and unworkable septic tanks for the small town of 288 residents.

But many fear sewers will turn the rural northwestern corner of Prince William County, and this former hay market, into just another Washington suburb. Sewers and the recently opened I-66 exit, on the town line, invite development.

For more than 20 years, Virginia health officials have been declaring Haymarket's water supply system a health hazard. Town officials tried to get sewers in the 1960s but were blocked in court by residents who feared sewers would bring development, Mayor Muriel Gilbertson said.

Gilbertson, 77, a driving force behind the sewers, was elected to the Town Council in 1976 as a write-in candidate.

With the help of county, state and federal funds, she and the council have gotten sewers and new roads at a cost to the town of a little more than $36,000. The about 90 buildings in Haymarket will be charged $6 a foot to tie into the line, as well as an annual sewer charge.

"We will probably have some small, wild celebration" when the sewer is officially opened next month, Gilbertson said.

Then residents, who must pay annual sewer charges whether they connect to the new sewer, can begin to look forward to clearer, cleaner well water because most septic tanks and many pit outhouses--which leach into the wells--will be closed. Residents will no longer have to buy water or carry it in buckets and jugs from the few town wells that have not been polluted.

But now that the sewers are in, I-66 has arrived and developers already are knocking at the door, said Gilbertson, the town has still another controversial task ahead: to establish a zoning plan.

It's been on the council agenda several times and put off until summer because a number of residents don't like zoning, fearing that it-- like sewers--may bring development and urban complications to this still peaceful rural town.