State Street businesses will have to wait longer than expected for their local bridge to reopen and for traffic to return to normal.

The State Street Bridge, which has been closed for construction since 2009, is scheduled to reopen next year. Construction has been plagued with obstacles, extending for four years past the original 2011 reopening date and affecting both local businesses and residents.

“We are doing our best,” said Vladislav Kaminsky, supervising engineer for the Connecticut Department of Transportation. “Our main priority is to give the road back to the residents.”

The bridge will open in April 2015, although construction is not anticipated to be finished until August of that year. The engineers do not foresee any more complications since they have completed the underground portion of the bridge, said Joe Moslehi, chief structural engineer in the city of New Haven Engineering Department.

Plans for reconstruction of the bridge began in 2009, when a DoT inspection report indicated that the bridge, originally built in 1920, was not safe or wide enough to support the amount of traffic it now sees. The City of New Haven is overseeing the design of the bridge, while DoT is managing construction.

The first of many delays arose shortly after construction began. The drilling was determined to be too close to a 42-inch, cast iron water main that served a large portion of the city.

“When you’re dealing with real things, like people’s water, you can’t take risks,” said Larry Smith, assistant city engineer.

Over the next five years, the engineers encountered numerous additional problems with utilities and potential environmental hazards.

So far, the problems that have hindered the construction have been a financial burden as well. The original cost estimate for construction of the bridge by the DoT was $5 million, but the number has quickly grown to over $25 million. The city’s design costs are currently estimated to be just under $600,000.

“This is one of those jobs in which we have just been completely unsuccessful until this point,” Kaminsky said.

State Street, which was often used by commuters traveling between Hamden and New Haven, now sees far less traffic, said Jessica Holmes, alder for Ward 9, which includes the State Street Bridge. Signs warning drivers about the closed bridge direct traffic to detour routes.

But, the complicated detours often discourage drivers, who are only willing to take the potentially dangerous detours in daylight, said Fred Walker, co-owner of Chestnut Fine Foods, a specialty food shop located on State Street near the construction site. The detours also redirect traffic to streets that are used to getting less traffic, like Nash Street and Mechanic Street, Holmes said.

“The kind of community that we’re trying to build in New Haven is a fluid, pedestrian- and bike-friendly one,” Holmes said. “This blockage makes getting around much harder.”

The neighboring commercial area has felt the effects of the construction. The dead end formed by the closed bridge repels customers, who are unsure how to turn around, Walker said. His store has survived largely due to its catering and delivery business, but walk-in business has decreased by 20 to 30 percent due to customers taking the detour before reaching his store, which is located one block away.

Business owners have been frustrated by the series of delays. A meeting was held last November for local business owners and city and state officials to discuss the current status of the bridge. The city has attempted to address business owners’ complaints of an increase in crime by installing more lights by the construction site, Moslehi said.

In response to the announcement of the April 2015 reopening, Holmes expressed “cautious optimism.”

Some business owners, including John Ortiz, president of Agency One Group Inc, want to discourage further delays. Ortiz suggested imposing a fine for each day past April 2015 that the bridge is not reopened.

Other business owners said they are simply looking forward to the reopening. Walker hopes to plan a big street festival to celebrate. A festival could draw customers back to the stores near the bridge, but won’t compensate for the loss of revenue over the past six years, he said.

“I’ve been told so many different dates,” Walker said. “I’m not going to believe anything until I see it.”

The State Street Bridge is 88 feet long and crosses Mill River.