Inspectors need to quickly assess the nearly 3,000 dams in Massachusetts, and the state must be prepared to spend tens of millions of dollars on improvements, a legislative report released Tuesday says.

The report by the Senate Post Audit and Oversight Committee found emergency plans are lacking for the vast majority of "high hazard" dams — dams that could cause significant property damage or deaths if they fail.

"Given the potential impact on communities, dam safety and maintenance should be a top priority for the state," the report said.

The findings mirror the results of an investigation last year by The Associated Press, which examined dams throughout southern New England. The AP review of documents in Rhode Island, Massachusetts and Connecticut, as well as interviews with state officials and dam owners, showed many dams are not inspected as often as they should be, and some go years without recommended repairs.

The Senate report was released as flood waters from five days of heavy rain taxed several Massachusetts dams. In Methuen, hundreds of residents downstream of the Spicket River Dam left their homes fearing it would give way.

The report found the structural condition of nearly half of the dams in Massachusetts has yet to be assessed.

It recommended inspecting all high and significant-hazard dams; increasing fines from $500 per day up to $25,000 per violation of state dam safety regulations at high or significant-hazard dams; and hiring more dam safety inspectors. It also calls for increased spending, including $10.3 million for improvements to state-owned dams and the creation of a fund to provide low-interest loans to repair or remove dams.

The report also faulted Gov. Mitt Romney for including only about half of the $1 million requested by the state Office of Dam Safety in his proposed budget for the new fiscal year.

The investigation into the state's dams was launched after floodwaters last October pummeled the 173-year-old Whittenton Pond Dam in Taunton, threatening the downtown area and closing businesses, highways and schools. Workers ultimately replaced the structure by pouring tons of boulders and rocks at the foot of the dam.

In response, Romney ordered an emergency inspection of 186 of the state's most critical dams. That review discovered eight in need of immediate attention.