The Manasquan Reservoir has reached historic low levels due to the ongoing drought in New Jersey.

The reservoir in Howell, which can supply as much as 30 million gallons of water per day to the water utilities serving Monmouth County, held 2.3 billion gallons of water on Monday and was about 49.35% full — according to Marc Brooks, the executive director of the New Jersey Water Supply Authority.

“That’s an all-time low since the early 1990s, when it was only that low because it was the first time it was filled,” Brooks said in an email.

The reservoir, built in 1990, has a capacity of approximately 4.67 billion gallons.

The reservoir is part of a network that provides drinking water to more than 1.2 million people in Central New Jersey.

It is now at an altitude of about 30 meters above sea level, which is 11.73 meters below high seas, Brooks said. By mid-October the reservoir was at 58% capacity.

According to the U.S. Drought Monitor, Monmouth County, like most of the state, is experiencing a severe drought. Some southern provinces are facing even more severe ‘extreme drought conditions’.

There has been only one day of light rain in New Jersey since late September. Some relief is expected Wednesday evening, with forecasters expecting 1/2 to 1 inch of rain in central New Jersey and 1 to 1.25 inches in northern counties.

The state Department of Environmental Protection issued a drought warning in New Jersey last week, amid an unprecedented wave of dry weather that has led to shrinking water supplies and a wave of wildfires.

New Jersey American Water has issued a mandatory conservation notice for all customers in the state. The company urged customers to limit all non-essential water use, including outdoor watering until spring and conserve water indoors as much as possible.

“We are committed to responsible water management and are prepared to support the action by Governor Murphy and the NJ DEP to place New Jersey on drought alert status,” said Mark McDonough, president of New Jersey American Water. “Our customers can rest assured that we are closely monitoring water conditions and are prepared to take additional actions to support statewide water conservation efforts. However, it is crucial that everyone works together now and saves water.”