After a summerlong reprieve from the traffic snarls, torn up streets and endless detours that marked last winter in downtown Tisbury, construction resumes this month on the town's $10 million wastewater project.

"The worst of it is over," said town administrator Dennis Luttrell this week. "A lot of the work will be done off the roads, and we don't expect to be working into the winter."

Although a schedule has not been set for the fall, project manager Joe Federico, of BETA Engineering, said sewer construction may begin as early as next week. And what's on tap over the next few months will be less intrusive than what the town saw earlier this year.

The main sewer lines are in along Main street, Lagoon Pond Road and other side streets - which means no more tearing into the pavement downtown.

The lateral pipes that branch off the main line have also been installed as far as the individual property lines. That leaves connections to be made linking the lateral pipes to homes and businesses.

On Main street the lateral pipes stop directly beneath the sidewalks, so making the connection means ripping up some concrete and brick. The individual property owners must hire their own private contractors to do the work, which will lead to spotty disruptions over the coming months.

The wastewater system works through a combination of gravity feed pipes and grinder pumps. The pipes along Spring and Center streets, for example, run naturally toward the central collection site, located near the police station and public rest rooms. Properties below the central site, such as those on Lagoon Pond and Beach roads, get grinder pumps that will mulch and push waste up toward the central site. Between 80 and 90 pumps will be installed this fall.

The central collection site, also on the project schedule this fall, has two elements: what Mr. Luttrell called "the deep well," for waste collection, and a larger pump station. The station will give waste the big push toward the treatment plant, located up State Road behind the landfill.

The station will be housed in a wood frame building. Mr. Luttrell said the town has learned a lesson from Oak Bluffs - "no little green boxes all over the place" - and is doing its best to hide the visual impact of the system.

There's a small connection to be made between Beach and Lagoon Pond Roads and several manholes still need to be installed, including one at Five Corners.

Construction of the treatment facility has continued throughout the summer, and it may be ready for testing as early as January.

The wastewater system, designed to handle about 104,000 gallons per day, is slated for 113 users. Selectman Tom Pachico, who is also the town's board of health agent, indicated at the Tuesday selectmen's meeting that the estimated flow rates for the individual properties were slightly off the mark.

Mr. Pachico explained yesterday that some properties were lumped together for a combined flow rate - such as a business with an apartment above - when they should have been calculated separately.

"The total package will still fall within the maximum capacity," he said. "On paper, we may wind up needing as much as 90,000, although when the system turns on it will probably be even less - more like 60,000 or 70,000."

The project is ahead of schedule and under budget, although a $68,000 change order approved by the selectmen Tuesday brings the town closer to the budgeted $8 million construction costs - that's for both the treatment plant and the sewer lines. With other capital costs, the project will come in at around $10 million.

The town is financing part of the project with a $6 million loan from the state revolving loan fund, which will be repaid with no interest over the next 20 years. The town also received a $1.3 million federal grant from the U.S. Department of Agriculture.

After the grant, Tisbury taxpayers are picking up half the remaining project cost; the property owners who are tied into the system will cover the other half through service betterments.

In the next few weeks selectmen will schedule a workshop with system users to discuss options for the betterment process - which seeks an equitable way of paying back the cost of the project. For example, betterments can be set at a flat rate per user, or at a cost proportionate to a property's square footage.

Anticipating the workshop, selectman Tristan Israel declared: "We'll all get educated, and then freak out."