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DNRC Headquarters
1539 Eleventh Ave. Helena, MT 59601
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Proposing to Repair an Existing Dam

*NEW* - Dam Safety Design Review Process Guidelines

Does your dam require permits from the Dam Safety Program?

So the Dam Safety Program asked you to hire an engineer.

*Outlet Works Rehabilitation Guide for Small Dams - This guide uses short stories and photos to illustrate considerations that dam owners, engineers and regulators must take into account when outlet rehabilitation is on the horizon. This is not intended to be a design guide. Rather, this guide highlights past experiences and lessons learned from others. Cautions and concerns are noted and resources for additional information identified. This guide was developed on the premise that informed dam owners make wise decisions. Wise decisions result in a successful project.

If you determine that your proposed dam falls under permitting authority of the Dam Safety Act:

Step 1  Apply for a downstream Hazard Classification ($125 fee).

If your dam has been previously classified by the DNRC Dam Safety Program, please call your local Dam Safety Program Engineer to discuss first; in some circumstances, previously classified dams do not need a new hazard classification.

Step 2 If your dam is classified as “high hazard”, you must obtain a Construction Permit (no fee).

A Construction Permit application must be accompanied by construction plans and specifications and an engineering design report. The plans, specifications and report must be prepared by a licensed professional engineer experienced in dam design and construction.

Step 3  Obtain other applicable permits - Stream Permitting Guide


Step 4  Once your repair is complete, you must obtain an Operation Permit.

Operation permits are issued for 5 year periods. To obtain an operation permit, your dam must have a detailed inspection completed by a licensed engineer and a report submitted to the DNRC Dam Safety Program. An operation plan must also be prepared. The operation plan consists of reservoir operation procedures, maintenance procedures for the dam and appurtenant works and emergency procedures.

Step 5  Annually update the Emergency Action Plan and conduct an Owner’s Inspection

Step 6  Every five years, the Operation Permit must be renewed.

To renew the Operation Permit, an inspection of the dam must be completed by a licensed professional engineer. The operation plan must also be reviewed and updated as necessary.