As the dry weather continues in Maryland, hydrologists are beginning to worry about falling water tables. The U.S. Geological Survey's monitoring wells in Baltimore and Frederick counties have been falling since mid-February - a period when they should be continuing their winter recharge.

Once things green up, plants and trees will be taking up much of whatever precipitation we receive, diverting it from reaching the streams and groundwater on which well water depends.

"This is of concern," the USGS said yesterday. "If dry conditions persist in the region into the summer, some shallow domestic wells may be unable to supply sufficient water to meet demands."

Those of us on public water systems have less to worry about, for now. Baltimore's reservoirs remain in good shape for this time of year, public works officials have said. And municipal systems that rely on well water generally tap into deeper aquifers that are less vulnerable to year-to-year weather events. (Although those aquifers, too, have been falling for years due simply to rising demand and recharge cycles measured in decades or centuries.)

In the map above, the dark brown color shows where 7-day average streamflow is running at 5 percent or less of historical averages for this time of year.

For the moment, at least, the forecast looks rainier than it did yesterday. There's a little on tap for tonight, and as much as a half-inch due tomorrow. But we remain almost 10 inches in arrears for the first three months of the year.