Boston-based Nitsch Engineering, an engineering and land surveying firm, is providing surveying and civil engineering services associated with the renovation of the Chelsea Street movable bridge, spanning the Chelsea River between East Boston and Chelsea.

The project involves replacing the existing 140-foot Straus-Heel Trunnion bascule span with a 380-foot vertical lift span. The new higher clearance was deemed necessary by the U.S. Coast Guard to improve navigation on this critical channel.

Nitsch previously provided civil engineering services related to the roadway reconstruction of Chelsea Street, including plans, roadway profiles, utility relocations, drainage modifications, traffic controls and property easements. Nitsch also performed a detailed topographic survey of the Chelsea Street Bridge, including the approaches from East Boston and Chelsea, and determined the existing right-of-way and U.S. Pier & Bulkhead line, according to a statement.

The construction is being funded through the Massachusetts Recovery Plan, which integrates state resources with federal funding from the American Recovery and Reinvestment Act. Construction began in March 2009, and is anticipated complete in 2012.