March 25, 2024

Ms. Kathleen Callister

Adaptive Management and Water Quality Division Manager

U.S. Department of the Interior

Bureau of Reclamation

125 South State Street, Room 800

Salt Lake City, UT 84138

Submitted electronically via LTEMPSEIS@usbr.gov

Dear Ms. Callister,

American Whitewater appreciates the opportunity to provide comments on the draft

Supplemental Environmental Impact Statement for the Glen Canyon Dam Long Term

Experimental and Management Plan.

American Whitewater is a national 501(c)(3) non-profit organization with a mission to protect

and restore our nation’s whitewater resources and enhance opportunities to enjoy them safely.

With over 7,000 individual and 80 affiliate club members, American Whitewater represents the

interests of over 80,000 river enthusiasts nationally. As conservation-minded whitewater

recreationists, we place a high value on protecting naturally functioning river ecosystems,

including their fish and wildlife, geomorphic processes, and potential to provide clean and safe

drinking water.

American Whitewater is the primary advocate for the preservation and protection of whitewater

rivers throughout the United States, and we have members that live, recreate, and depend on

the outdoor economy of the Colorado River Basin. American Whitewater and our members are

invested in ensuring that management of the Colorado River Basin is informed by science,

traditional ecological knowledge, robust public participation, and that the ecological and

recreational values of the Colorado River Basin are adequately included in operations of Glen

Canyon Dam. American Whitewater has also been closely involved in the NEPA processes for

the short and long term operations of Lake Powell and Lake Mead.
Comments on Alternatives:

No Action Alternative

On page 3-23, the draft SEIS says that under this alternative, there will be no impacts to

hydropower. This needs to be restated to clarify that if no action is taken, conditions for

endangered species will rapidly deteriorate and more severe action will need to be taken. The

longer that action is delayed, the near-future impacts to hydropower are likely to increase

significantly. The specific impacts may be unknown at this time, but it needs to be

acknowledged that the No Action Alternative will assuredly lead to greater impacts to most

resources if small mouth bass can’t be controlled and impacts to endangered species becomes

more severe.

Non-Bypass Alternative

The Non-Bypass Alternative has unacceptable impacts to whitewater recreation in the Grand

Canyon and should not be further considered. This alternative includes flows in the Grand

Canyon as low as 2,000 cfs for up to 4 hours a day once a week,1 which would significantly

disrupt both private and commercial boating trips in the Grand Canyon, a $46 billion industry.2

Flows of 2,000 cfs are not only extremely dangerous for boaters, they are unnavigable for

common types of boats in the grand canyon. Flows this low would be in direct violation of the

Grand Canyon Protection Act of 1992 (GCPA), which directs that recreation needs to be

protected as a valued resource in the Grand Canyon.3 The GCPA’s purpose was to address the

negative impacts of fluctuating reserving releases on downstream environmental and

recreational resources.4 It would be impossible to attempt to only operate flows as low as 2,000

cfs during the nighttime (9pm to 1am) because of the delay that it takes outflow water at Glen

Canyon Dam to reach rapids and campsites up to hundreds of miles downstream. This nuance

is duly noted in the SEIS on page 3-188, but the reasoning is not sufficiently applied to the

Non-Bypass Alternative.

The campsites in the Grand Canyon are heavily dependent on sandbar availability and river

flow levels; campsites that are available at 2,000 cfs are likely not available at 27,000 cfs and

vice versa. Even if you were able to plan ahead for the flow fluctuations, and typical Grand

Canyon trips would have at least 3 flow fluctuation events during their trip, it would severely

reduce the available camp options and certainly cause a lot of confusion. Available campsites

1 Draft SEIS, 2-17 2 https://www.flagstaffbusinessnews.com/canyon-river-outfitters-impacting-local-economy/ 3 https://www.congress.gov/bill/102nd-congress/house-bill/814/text?r=33&s=1

4 https://www.congress.gov/bill/102nd-congress/house-bill/814/text?r=33&s=1
have already decreased by over 30% since 2007 due to decreased amounts of sand in the

canyon.5 Rapids in the Grand Canyon would also become unnavigable at flows as low as 2,000

cfs, causing safety hazards and logistical issues for trips that are already very complicated to

plan. The proposed low flows are 3,000 cfs or 60% lower than the 5,000 cfs minimum

identified in the LTEMP ROD and would represent a drastic change in flow conditions.6

American Whitewater and our members are strongly opposed to the Non-Bypass Alterative and

we ask that it is removed from further consideration.

Cool Mix with Flow Spike Alternative

The Cool Mix with Flow Spike Alternative is American Whitewater’s preferred alternative

because it achieves the control of small mouth bass, while also having positive impacts to

recreational opportunities in the Grand Canyon and relatively minimal impacts to other

resources. The Draft SEIS states that the two flow spike alternatives would have the greatest

potential to increase campsites in the Grand Canyon compared to other alternatives.

Additionally, the cool mix alternatives would lead to fewer fish kills compared to the cold

shock alternatives, which is more in line with tribal practices and beliefs as stated in the Draft

SEIS on page 3-178.

In the implementation of this alternative, American Whitewater requests that close coordination

with the HFE program occur so that Glen Canyo Dam operations under this alternative support

rather than negatively effect the desired outcome of HFEs. This means that flow spikes must be

managed with the latest science on sediment accounting in order achieve multiple benefits of

small mouth bass management and sandbar development for campsites in the Grand Canyon. It

has further been determined that flow spike durations of 72-hours have a much higher

likelihood of transporting sufficient amount of sand, compared to the 36-hour timeframe

proposed in the Draft SEIS. We greatly appreciate that across all alternatives, HFE

management will be adjusted to incorporate the best available science on sediment accounting

periods and implementation windows.7

5 Draft SEIS, 3-186 6 Draft SEIS, 2-18 7 Draft SEIS, 2-2
Comments on Recreation Impact Analysis:

American Whitewater appreciates inclusion in the SEIS of published scientific research that

documents whitewater boating opportunities in the Grand Canyon, the quality of the

recreational experience, and its economic impact at various flow levels. Studies referenced in

the SEIS include Neher et al. (2017)8 and Bishop et al. (1987).9 Additionally, Shelby et al.

conducted a study in 199210 describing preferred flows for both commercial and private

whitewater trips in the Grand Canyon. The Shelby et al. (1992) study should also be used to

inform the analysis of impacts to recreation in the Final SEIS.

Thank you for considering these comments on the draft SEIS for the Glen Canyon Dam Long

Term Experimental and Management Plan.

Sincerely,

Kestrel Kunz

Protection Director

Southern Rockies Program

American Whitewater

kestrel@americanwhitewater.org

Hattie Johnson

Restoration Director

Southern Rockies Program

American Whitewater

hattie@americanwhitewater.org

8 Neher, C., Duffield, J., Bair, L., Patterson, D., & Neher, K. (2017). Testing the limits of temporal stability:

willingness to pay values among grand canyon whitewater boaters across decades. Water Resources

Research, 53. https:// doi.org/10.1002/2017WR020729 9 Bishop, R.C., K.J. Boyle, M.P. Welsh, R.M. Baumgartner, and P.R. Rathbun, 1987, Glen Canyon Dam

Releases and Downstream Recreation: An Analysis of User Preferences and Economic Values, Glen

Canyon Environmental Studies, Flagstaff, Arizona., Jan. 10 Shelby, B., Brown, T., Baumgartner, R. (1992) Effects of Streamflows on River Trips on the Colorado

River in Grand Canyon, Arizona. Rivers, 3(3), 191-201.

https://www.americanwhitewater.org/content/Document/fetch/id/518/.raw