Navajo Reservoir Release Increase 6/19 - San Juan

[sjnovak3]

BUREAU OF RECLAMATION
NAVAJO RESERVOIR RELEASES
June 19, 2012
SENT VIA FAX AND E-MAIL

As a result of decreasing river flows in the critical habitat area of the San Juan River and a hot and dry forecast, the Bureau of Reclamation will be increasing the release from Navajo Reservoir to 800 cubic feet per second (cfs) on Tuesday, June 19, 2012, beginning at 9:00 a.m. Releases are made for the authorized purposes of the Navajo Unit, and to attempt to maintain a target base flow through the endangered fish critical habitat reach of the San Juan River (Farmington to Lake Powell).
The San Juan River Basin Recovery Implementation Program recommends a target base flow of between 500 cfs and 1,000 cfs through the critical habitat area. The target base flow is calculated as the weekly average of gaged flows throughout the critical habitat area.

This scheduled release change is subject to changes in river flows and weather conditions. If you have any questions, please contact Ryan Christianson at 970- 385-6590 or e-mail him at [email protected].

Susan Novak, P.E.
Hydrologic Engineer
Reclamation
Western Colorado Area Office
[email protected]
970-385-6560

[cosurfgod]

I have a permit for July 7 on the San Juan. Is there an estimate on how long the releases will last?

Thank you.

[sjnovak3]

Yes, this release will last for a while, as hot and dry conditions continue. However, keep in mind that an 800 cfs release from the dam does not mean that there will be the same flow down in Mexican Hat. There are 150+ miles of evaporating river, tributaries, and diversions in between.

Susan Novak, P.E.
Hydrologic Engineer
Reclamation
Western Colorado Area Office
[email protected]
970-385-6560

[Cutty]

Thanks for the update Susan - so just how much water eventually gets down to Sand Island and Mexican Hat on average? And how long does it take to get there? We're doing SI to MH on the 28th and it would be nice to have at least 500cfs.

[sjnovak3]

It's hard to say exactly how much- depends on the time of year, weather, and several other factors. Our target base flow in the critical habitat reach is 500 cfs (averaged throughout the San Juan from Farmington down to Bluff), and our releases are calculated in an attempt maintain this. It generally takes around 3 days for effects from the dam release to show up around MH.

Susan Novak, P.E.
Hydrologic Engineer
Reclamation
Western Colorado Area Office
[email protected]
970-385-6560