ALBUQUERQUE — New Mexico’s reservoirs are shrinking because of a persistent drought, and officials with the State Parks Division said Thursday they are being forced to close boat ramps throughout the state as a result.

Officials said water levels at many state park lakes are extremely low and the ramp closures are in place to address public safety concerns and to prevent property damage during the launching and loading of boats.

Storrie Lake State Park near Las Vegas, N.M., closed its boat ramp to all motorized vessels effective immediately Thursday. Other boat-ramp closures are in effect at Clayton, Conchas, Heron and Santa Rosa lakes.

One ramp at Elephant Butte Lake, the state’s largest reservoir, is closed. The North Ramp at El Vado also is off limits.

Park officials said visitors still will be allowed to hand launch paddle craft or small vessels from the shorelines.

The latest drought map shows much of the southwestern U.S. is mired in drought. In New Mexico, more than 52 percent of the state is dealing with exceptional drought, which is the worst category. A year ago, that percentage was zero.

While there have been more dry years than wet ones over the past two decades, parts of New Mexico missed out on last summer’s monsoon. Winter did not result in much snowpack, and the rain this spring has been far from enough to put a meaningful dent in the deficit.

Climate experts say most of the rain that has fallen in recent weeks has been soaked up by the dry soil, meaning there is less storm runoff that makes its way to the state’s streams and rivers and ultimately the reservoirs.