Dam Break Approval 1

[SMIAH]

I have an ongoing project regarding the available software to perform dam break simulation.

At this point, I would like to have some information about the approval of a Dam Break simulation project in USA.

Is it different in every state? Is the FEMA involved in it?
Depending on who's approving, what is the position regarding the use of HEC RAS to perform a complex dam break analysis?

Any information would be welcomed!

Thanks

 

[cvg]

depends a great deal on who owns the dam, who regulates it, on the size and somewhat on choice of the engineer. FEMA generally does not get involved with regulation of dams. There are a number of possibilities for dam owner/regulator:

[ul]
[li]power company regulated by FERC[/li]
[li]Federal government regulated by USACE, USBR, NRCS and/or local sponsor[/li]
[li]local government regulated by state or not regulated at all[/li]
[li]privately owned regulated by state regulated or not regulated at all[/li]
[li]small dams may not be regulated if they don't meet criteria for height and storage[/li]
[/ul]

HEC-RAS is often used for analysis

 

[Drew08]

Just to add to cvg's response:

FERC only regulates dams used for hydropower. Other power related dams (e.g., ash settling ponds, cooling ponds) are not regulated by FERC and default to state regulation. In the future, EPA will likely get their hands into regulating ash ponds, but have no jurisdiction yet.

Other Federal agencies only regulate dams constructed under the authority of the agency or with agency money, and are typically still required to meet state criteria. Particularly those built on private lands, such as NRCS flood control structures, are still regulated by the state.

Likely 99% of all medium to large dams are, or should be, regulated by the state dam safety office. Each state has different rules and guidelines relating to methods and models used for dam break analyses.

Most state dam safety offices have published engineering guidelines that lists acceptable models. Nearly all list NWS DAMBRK, now BOSS DAMBRK. As many believe, HEC-RAS is not universally accepted. Some states don't accept third party analyses, and do everything internally or contract out themselves.

 

[SMIAH]

Interesting sentence:

"As many believe, HEC-RAS is not universally accepted".

But, it appears that NWS will include RAS into their suite of Hydraulics models and they're currently working about the conversion of existing FLDWAV models into RAS ones.

 

[cvg]

regarding your comment: "... NWS will include RAS into their suite of Hydraulics models and they're currently working about the conversion of existing FLDWAV models into RAS ones."

NWS is not responsible for regulating any dams that I am aware of. The regulatory agency will be the one to accept your dam break analysis and they will set the criteria for that analysis including what software might be acceptable.

 

[SMIAH]

Indeed - Good point (again!)