Frequently Asked Major Water User Questions

Water Resources Center fact sheet
Missouri Geological Survey Director: Joe Gillman

What is a Major Water User?
Any surface or groundwater user with a water source and the equipment necessary to withdraw or divert 100,000 gallons or more per day (70 gallons per minute) from any stream, river, lake, well, spring or other water source is considered a major water user in Missouri. Additionally, any combination of withdraws (wells, surface water pumps or diversions) that withdraw or divert 100,000 gallons or more per day (70 gallons per minute) also qualifies as a Major Water User. See RSMo 256.400

Are there any fees associated with registering as a Major Water User or reporting annual water use?
No fees are assessed to register as a Major Water User or to report annual water use.

How often is Major Water User registration required?
Registration is required by law for all major water users. Registration is one time to get a Major Water User identification number. Once you are registered as a Major Water User you can add, delete or transfer water withdrawal points.

When is the annual reporting due each year?
Annual reporting should be completed by March 31 for the previous calendar year.

Example: Water used between Jan. 1 and Dec. 31, 2012 can be reported between Jan. 1 and March 31, 2013.
noneNote: To provide water use information for previous years, contact the Water Resources Center at 573-368-2175 or 417-891-4392.

What will happen if I do not submit my water use data?
While there are no penalties for not reporting water use data, failure to report may result in referral to the Missouri Attorney General.

Why does the state collect this data?
Water use data is vital for ensuring water use needs are met. In order to determine whether existing water resources will be adequate to meet water use demands of Missouri citizens, we must know how much water is being withdrawn annually.

Do other states have similar requirements for water use registration?
Yes, most states have either a water use registration such as Missouri, or they have water rights/water allocations program.

How do I register as a Major Water User and report water use?
You can register online or download and print forms at If you would like assistance or have questions, call 573-368-2175 or 417-891-4392.

Printed registration and reporting forms can be mailed (or faxed to 573-368-2193) to:

Missouri Water Resources Center
PO Box 250
Rolla, MO 65402-0250

What is my Major Water User identification number?
This 8-digit identification number is unique to each Major Water User. One or many surface/groundwater withdrawal points will be associated with this number.

Who reports water use if a water source is used by someone other than the owner?
It is always the water user who is responsible for reporting water use. The water user may or may not be the property owner.

How much surface water or groundwater can I take from a water withdrawal point?
There are no state laws, regulations or policies that specify how much water may be used. Missouri is a riparian water law state, which means, all landowners touching or lying above water sources have a right to a reasonable use of those water resources. Recent case law has established the reasonable use criteria that the State Supreme Court has been following. Reasonable use requires that other users and landowners not be overly adversely impacted.