Drinking water delivered by the Humboldt Bay Municipal Water District (HBMWD) is drawn from wells located in the Mad River northeast of Arcata, California. These wells, called Ranney Wells, draw water from the sands and gravel of the aquifer under the riverbed at depths of 60 to 90 feet. The gravel and sands through which the water is drawn provides a natural filtration process which yields source water for HBMWD's regional drinking water system that is of very high quality.