CONCORD— The State of New Hampshire will compensate towns along the Merrimack River for payments owed by the state of Massachusetts, under a bill approved by Senate and House lawmakers on Thursday.

The Senate members of a conference committee largely agreed to changes made to Senate Bill 326 in the House. Under the bill, the state would pay the communities the money they have not received in the current budget year, around $496,000. The money would be allocated in the next budget year.

Lawmakers had discontinued the practice of paying the towns this year.

The chief sponsor of the bill, Sen. Andy Sanborn, R-Henniker, said that the state has an obligation to cover the tax assessments for land given up by 14 towns that belong to the Merrimack River Valley Flood Control Compact and the four towns in the Connecticut River compact.

“There’s no question to me that this is money the state owes these towns,” he said. “These communities have no authority to press action against Massachusetts; only New Hampshire can do that.”

Officials with the Attorney General’s Office and Department of Revenue Administration say they are actively pursuing these claims against Massachusetts. The officials have  estimated that Massachusetts owes more than $4 million in payments over several years.

Under the 1957 Merrimack River agreement, Massachusetts was supposed to pay 70 percent of the lost tax value of the land given up by the New Hampshire communities to control flooding downstream. In recent years, Massachusetts has stopped paying, or only partly paid, the amount owed to New Hampshire. Bay State officials say they’re working with New Hampshire officials to resolve the disputed payments.