U.S. Department of the Interior

U.S. Geological Survey

Science Plan for a 2008 ExperimentaBeach/Habitat-BuByJohn Hamill, ChiefTed Melis, Deputy ChiefMatthew Andersen, Biology Helen Fairley, Socio-CulturaCarol Fritzinger, Logistics anGlenn Bennett, DASA PrograGrand Canyon Monitoring anTechnical Work GroupDecember 5, 2007
Overview

 Review major elements of the Be

Building Flow (BHBF) Science Pla

 Background, purpose, and scope Results of past BHBF tests Science questions addressed Timing, duration, and magnitude Costs Long-Term Experimental Strategy Experimental Study Plans
Final TWG Review

October 5, 2007The TWG considers that the GCMRC’s BHBF Science P

technically adequate and recommends that AMWG that AMWG consider the following issues in relation budgeting:

 Sandbar and nearshore habitat responses Assessment of nearshore and food base re Native and nonnative fish movement and p

responses to the BHBF and in relation to chconditions, where seasonally appropriate, athe adequacy of overall HBC monitoring

 A comprehensive economic analysis of BH

impacts

 Integration of past BHBF and related ecosy

into overall ecosystem structure and functi

TWG recognizes that the BHBF Science Plan should be 

policy standpoint by the AMWG.

Yes: 13; No: 7
Review/Decision Making Pr

 Agency & Peer Review of Science Plan (F

 BOR, NPS, FWS, WAPA, and AGFD prelimin Independent Science Advisor review

 TWG Review of Science Plan (May-Oct 200 DOI/AMWG Policy Review (Nov 2007 to pre

 Revise Plan based on TWG/AMWG concerns

 DOI Decision Timeline

 Dec 3-7: Formal DOI proposal? GCMRC spendin Dec 10-12: Final BHBF Science Plan Dec 07 – Feb 08: Compliance and permitting Mid Feb 08: Final DOI Decision
Why Sand?

86% reduction from predam sand levelsImportance of Sandbars Aquatic Habitats – nursery habitats 

for native fish

 Terrestrial Habitat – substrate for 

riparian vegetation

 Archaeological Site Preservation –

most archaeological sites buried in sand/silt

 Recreational Campsites
Purpose and Scope

 Purpose: Build upon existing 

scientific knowledge to inform managers about the efficacy of using BHBF testing to rebuild not only sandbars, but also benefit various resources, particularly humpback chub.

 Scope: Addresses strategic 

science questions in the Monitoring and Research Plan (MRP) and builds on ongoing monitoring and research efforts

Pre-2004 

Post-20
Results of Past BHBF Tests

 1996 BHBF Test—depleted sand condi

 Sand does not accumulate in the riverbed o

period under normal dam operations

 When BHBF occurs under depleted sand co

sandbars erode

 2004 BHBF Test—moderately enriched 

conditions

 Increase in sandbars in Marble Canyon; ne

eddies downstream

 Increases in eddy-sandbar area are only po

enriched conditions;

 Sand from newly created bars may help pro

archaeological sites
Humpback Chub Response

 1996 BHBF Test: Valdez et al (2001)

 No decrease in HBC or other natives Temporary displacement of nonnatives

 Evaluation of 2004 test confounded by 

flood from LCR

 HBC stock assessment (Coggins, 2007

 BHBF did not adversely affect HBC  HBC adult population increased in 2004-05  HBC recruitment increased in 1996 and 20
Best Timing

For 2008, March is earliest practical time given lo

administrative, and safety constraints

March 2008 offers several advantages: Beginning of historic natural flood cycle System is sand enriched – 2-3 times 2004 leve

 Sand supply will erode over time although slow

 Immediately before spawning season--backwa

for native fish in spring and summer

 Minimizes impact on food base and trout cond Prior to tamarisk flowering Immediately before windy season – sand bars 

archaeological site protection

Concern: Trout fishing economic impact (prefer 
Peak Flow Magnitude and D

Replicate 2004 hydrograph

• 41,500 cfs for 60 hours

Precede and follow test with normal dam operations i.e., modified low fluctuating flowsImportant Differences:

• 2-3 times more sand; more evenly distributed• Normal MLFF flows will follow the test
Strategic Science Question

 Based on AMWG concerns and AMP G

 Tier off strategic s

questions in MRP

 Primary focus on s

humpback chub (bhabitats)
Sediment Science Question

Strategic Science Question: Is there a “flow-only

will rebuild and maintain sandbar habitats ovetimescales?

BHBF Science Questions1. How does suspended sediment concentration and gr

time and by reach under more enriched sand suppliebalance of sand following the BHBF test net positive, 

2. What is the minimum duration for BHBF tests needed 

sandbars under sand enrichment?

3. Can the next BHBF test increase campable areas at s

sustainable basis? 

4. How do post-BHBF flows affect the persistence of sa

backwater habitats used by humpback chub and othe
Humpback Chub Questions

Strategic science question: How importan

and vegetated shoreline habitats to the and survival of young-of-year and juveBHBF science question Do BHBF tests result in creation of 

habitats that may offer physical benhumpback chub and other native fis

 To what extent are backwater habita

BHBF used by humpback chub and fishes?
Cultural Resource Question

 Strategic science question: How 

are various treatments in slowinerosion at archaeological sites oterm?

BHBF science questions1. Do sandbars deposited by BHBF te

to preservation of archaeological sriver corridor? 
Other Priority Questions

 Strategic science question: How 

invertebrate flux affected by wateand dam operations?

 BHBF science question: How will a 

test affect food production and avai Impact rainbow trout in the Lees Ferry r Impact native fishes?
Other Priority Questions

Strategic science question: Do dam cont

affect rates of erosion and vegetation archaeological sites and TCP sites, an

BHBF science question Are open patches more susceptible to exo

colonization and establishment than sites vegetation following a disturbance? 
Other Priority Questions

 Lake Powell: Will a BHBF result i

nutrient releases and shrinking ohypolimnion?
BHBF Science Costs

 Estimated cost is over 2 years

 Year 1: $1.64 Year 2: $0.50

Total: $2.1 million

Option to reduce cost by funding a portion of 

 Available Funds (Experimental Fund on

 FY 08: $1.45 million FY 09: $ .50 million

Total: $1.95 Million

 Outside AMP funds may be available
Long-Term BHBF Strategy

At least several be required to a

• Sand supp• BHBF tests • Intervening • Long term only be detecumulative etests• Need to evunder range regimes and 

Modeling may rtests and costs
Questions/

Questions/Comments

Sandbar Response from 2004 BHB

(upper Marble Canyon)