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DNRC Headquarters
1539 Eleventh Ave. Helena, MT 59601
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Proposing to Build a New Dam


Step 1  Initial Planning


Make Sure Your Water Right is in Order

A water right is required to legally store water.  For more information please refer to:

Feasibility Analysis of Proposed Dam and Dam Site

DNRC recommends potential dam owners hire an engineer to conduct a feasibility analysis. This evaluation should include:

  • An assessment of soils in the reservoir pool area (can they hold water?)
  • Verify the source of water can sustain a reservoir.
  • Evaluation of the environmental and wildlife impacts if your dam will be located on a live stream. There are many factors to consider.
  • General configuration of the proposed dam (height, length, spillways, stored capacity, outlet configuration etc.)

  Step 2  Apply for a downstream Hazard Classification ($125 fee)

To build a new dam with an impoundment capacity of 50 acre feet or more, you must apply to the DNRC Dam Safety Program for a hazard classification.

More information on Downstream Hazard Classification

Dams classified as high hazard, and containing over 50 acre foot of water, are required to obtain additional permits from the DNRC Dam Safety Program.

Step 3  If your dam is classified as “high hazard”, you must obtain a Construction Permit (no fee).

DNRC has adopted a new process based on a national model to make the construction permitting process more efficient and less prone to late stage design changes. The process requires early involvement of the Dam Safety Program in reviewing construction designs.  For more information please refer to the Dam Construction Design Review Process.

A Construction Permit is the final stage in the Design Review Process and must be accompanied by construction plans and specifications and an engineering design report.


Step 4  Obtain other applicable permits 

 The dam owner is responsible for obtaining other applicable permits.  Other required permits depend on many factors including the type of dam owner (private, state, federal or local government), the owner of land under the dam (if different) and if the work is located on-stream or off-stream.  DNRC publishes an excellent reference Stream Permitting Guide that describes permits commonly needed to work on or near a body of water and who to contact for more information.

Step 5  Prior to storing water in your newly constructed dam, obtain an Operation Permit.

  For more information please refer to Dam Safety Web Page Permitting Your Existing Dam.

FOR DAMS NOT SUBJECT TO DAM SAFETY ACT CONSTRUCTION PERMITTING REQUIREMENTS (Not classified as high hazard, or less than 50 acre feet) please refer to the informative video


Hiring an Engineer

For a list of licensed engineers who work on dams in Montana, please contact the Dam Safety Program