Several Maryland counties lifted voluntary water restrictions after the region saw record rainfall in May, according to the Department of Public Works (DPW). 

Residents in Baltimore, Harford, Howard and Carroll counties were under a water restriction since early May due to historically low levels at Liberty Reservoir, a primary source of drinking water. 

Record rainfall in Maryland 

In early May, DPW Director Khalil Zaied said levels at Liberty Reservoir were at 4.5 feet, which was three feet lower than a comfortable level of 7.5 feet. 

"The main reason is the dry weather in the spring and the beginning of summer," Zaied said. "So we're really at a 20-year low in terms of rain coming in."

DPW said water levels at the Liberty, Loch Raven and Prettyboy reservoirs reached near-normal levels after the record amount of rainfall in May. 

Some operational changes at the Montebello and Ashburton Water Filtration Plants also helped by increasing reliance on the Loch Raven Reservoir, DPW said. 

Despite the improved water levels, DPW still urged residents to use water responsibly to protect the region's long-term supply and reduce water bills. 

Improvement to Maryland drought conditions

The record rainfall also aided in improving Maryland's ongoing drought. 

Experts say it takes a while for a drought to develop, and it takes even longer for it to improve. 

Evan Carrozza, with Baltimore County's Department of Environmental Protection and Sustainability, said we get the least amount of groundwater recharge during the summer. 

"That's because you lost a lot of evaporation, you have storm water runoff, and then you have vegetative uptake," Carrozza said. "So, plants and trees are taking a lot of that precipitation. You don't get as much recharge in the summer months." 

At the end of June, drought conditions improved significantly. Parts of central Maryland are still seeing moderate drought to abnormally dry conditions, according to the state's Department of the Environment (MDE). 

As of June 26, about 32% of the state is experiencing drought conditions, compared to about 71% on May 29, data from the U.S. Drought Monitor shows.