Utilities

For years, the Hultman Aqueduct was the only supply route bringing water from the Quabbin Reservoir to Boston. Construction of a second pipeline was thwarted by World War II delays and funding problems. By the 1980s, with the Hultman in need of repair, the Massachusetts Water Resources Authority (MWRA) rekindled the idea of a second water supply route: a 17.6-mile tunnel, bored between 200 to 400 feet below ground, not only would safeguard Boston's water supply, but tunnel construction would have little impact on the heavily populated MetroWest region. Working with Sverdrup (during design) and Stone & Webster (during construction), Nitsch Engineering performed a myriad of land surveying and civil engineering tasks for this multi-million dollar project.

• Our residential and industrial subdivision plans and cost estimates determined the future build-out of the properties taken by eminent domain for shaft sites.
• We performed a topographic and location survey at each of the shaft sites and community connections, and property line surveys of 400 parcels. Nitsch Engineering prepared 50 topographic and 86 taking plans for the project.
• Nitsch Engineering verified the tunnel's ongoing alignment during construction and monitored the Fayville Dam for deformation during construction of one of the shafts. Nitsch Engineering set a first-order control network using the Global Positioning System with traversing and leveling observations, to which all verification surveys were connected. We carried out shaft transfers using high-precision optical methods, and surveyed tunnel cross-sections using a reflectorless electronic total station. Nitsch Engineering maintained accuracy well within the contract limits and the hole-throughs were within tolerance.

Despite unforeseen conditions of tunnel excavation, Nitsch Engineering's surveys were completed on time and within the final established budget.

In 1999, the Boston Water and Sewer Commission (BWSC) began its $86-million sewer separation project aimed at lowering sewage treatment costs and reducing pollution levels in Boston Harbor and Dorchester Bay. "Soup-to-nuts" engineering — from preliminary analysis to construction administration — will be required to design separate pipes to handle sanitary sewage and stormwater. The project area is largely residential, with scattered commercial districts; approximately 234 roadways will be affected, and sewer separation will occur along major transportation routes, such as Dorchester Avenue and Neponset Avenue. Nitsch Engineering's role was to inspect residential and commercial buildings, and perform flow and dye tests to determine which buildings' roof drainage discharged to the ground surface, into the ground, or directly into the City's drainage system. We also performed land surveying to locate more than 900 BWSC manholes, catch basins, curb cuts, and other visible utilities within nearly 14 miles of roadways. Nitsch Engineering tied the locations to the North American Datum of 1983 and the Boston City Base vertical datum using the Global Positioning System, and used differential leveling from the National Geodetic Survey's first-order level line located along Gallivan Boulevard. All survey services were performed on time and within budget.