* Public Health Departments conduct water sampling for bacterial and viral contaminants
* Water districts control service to residential, commercial, industrial and institutional water consumers
===Flood and contamination control===
Water can become a natural disaster in the form of coastal or inland manifestions. These include tsunami, hurricane,cyclone, rogue wave and storm surge or floods originating from terrestrial water - bursting dams, rivers overflowing their banks. Planning and prevention of floods is a part of water resource policy which is separated from ordinary water resource management designed to allocate supply and provide for sanitation.
One jurisdiction's projects may cause problems in other jurisdictions, causing untold grief to all concerned. For instance, Monterey County California controls a body of water which acts as a reservoir for San Luis Obispo County. Who pays for measures to restrict growth of Quaaga Mussels? The down stream jurisdiction will face expensive damage to their piping systems if things get out of control, but boaters in the upstream jurisdiction will infect the lake if they are not subject to education and enforcement programs, which cost money. Similar examples abount.
== Subject matter jurisdiction: water quality issues ==