LOWELL — Construction is humming along on an apartment building for college students, with one portion of the building reaching five stories.

The Edge Merrimack River project first had to make a concession to the city before work began: it agreed that it would not sell the site to a nonprofit entity, such as UMass Lowell.

The project was approved by the Planning Board last June, but it still needed the city to agree to lease parking garage spaces for residents.

So in November, the developer, Vision Properties, agreed that if the property were to be sold to a nonprofit entity, that entity would have to pay property taxes as Vision or practically any other private owner would for a period of 10 years.

City Manager Kevin Murphy first pushed for such an agreement before the Planning Board approved the project, but the board backed off when representatives for the project said such a stipulation could make it difficult to win financing for construction.

The agreement, which has not been previously reported, was obtained at the request of The Sun. The city also agreed to help Vision obtain market-rate housing incentives or a tax break, which Murphy said would be “minimal” in size.

The city administration wanted the stipulation following the purchase last summer of the Perkins Park residential mill development by UMass Lowell. The property, which was assessed at $19 million, last paid the city $321,000 in property taxes.

UMass Lowell paid $61.5 million for the site, and agreed to pay property taxes on the site for this year after city leaders objected to the property being taken off the tax rolls.

Edge Merrimack River, with apartments for more than 400 college students across from Lowell High School, is slated to open by this fall.

Bill Martin, a Lowell attorney for the project, declined to comment.

A study conducted for the developers said the project will pay $3 million more in property taxes than when the site was the vacant former bank headquarters of Lowell Five.

Another recently approved housing development, with 240 units in a $40 million building, already agreed to such a stipulation.

That development, on Wellman Street between Chelmsford Street and the Lowell Connector, agreed that if it were to sell to a nonprofit, the nonprofit would have to make payments in lieu of property taxes.

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