phase i and ii channel restoration: summary and lessons ... · conclusions habitat and fish • a...

Photo credits, Erika Nortemann, Ellen Morris Bishop and Mark Godfrey

Phase I and II Channel Restoration: Summary and Lessons Learned

Vince & Dan Lamarra, ERI

Dave Gori, TNC

Matt Zeigler, NM Game & Fish Dept.

Michael Farrington, ASIR

© erika norteman/tnc 136N © Erika Nortemann/The Nature Conservancy © rfindling/tnc 130.7 10A © rfindling/tnc

© rfindling/tnc

Project Objectives

• Phase I Reconnect non-flowing secondary channels to the main stem SJR (ad hoc monitoring)

• Reconnect a Complex Secondary Channel System and Measure seasonal changes in habitat features & fish abundance over 3 yrs. (Site specific integrated monitoring)

-- Measure changes in habitat features associated with environmental flow releases & large floods

-- Compare abundance of SB fish collected in different meso-habitats to determine if preferences exist in restored channels

RERI Phase I Locations

Channel Observation since 1993

Restoration Success by Channel

Historical Comparisons Channel 130 North


660 cfs


475 cfs

Channel 130 North

Historical Comparisons Channel 130 South

Phase I Conclusions

• All restored Secondary Channels had improvements

in flow characteristics with a wide range in variability

• Channels can be engineered to flow at specific conditions

• Regardless of planning and/or engineering there is a measure of “chance” associated with the restoration success

Phase II Restoration Stage-Flow

Detailed Channel Flow Summer 2017

28 Days

Reduced Channel Flow Summer 2017

Flows @Tertiary A & B

Secondary Channel Temperatures

Channel Flow Conclusions

• The San Juan River had flows less than 475 cfs in August

and September 2017 that resulted in limited or no inflow into the channel

• The channel was flowing at 500 cfs prior to the 2017

spring runoff. Rootwad Pile was modifying inflow • Groundwater accrual may have kept the channel wet • During low flow periods, outflow temperatures were

warmer in the fall and cooler in the summer compared to the inflow temperatures

Transects @Tertiary A & B

Channel Profile @ Entrance (T-1)

Stage @ Secondary Channels (T-2, T-4, & T-6)

Channel Transect Conclusions

• The two Tertiary channels exhibited opposite trends in deposition/erosion over the three years of the study.

• The wetted channel in T-1 has remained stable but the

adjacent cobble bar has exhibited both erosion and deposition over the study period

• Two of the three main secondary channel transects have

remained neutral (T-2 and T-4) while the lowest most transect (T-6, Pit Tag) has had significant erosion and/or substrate removal

• The general pattern observed was erosion during spring

runoff followed by deposition over the summer monsoons and winter time periods

Secondary Channel Habitats


Runs = 80%

Habitat Seasonal

Differences in Main

Secondary

CO Pikeminnow Captures

Secondary Channel Fish CPM Densities by Date

Secondary Channel Fish CPM Densities by Habitat

Secondary Channel Habitats/Fish Relationships

Phase II Main Channel: X2 = 414.6, p < 0.0001 (n=48) Phase II MC & Reference: X2 = 351.3, p < 0.0001 (n=84)



>60X >6.3X >2.2X



<0.2X

Conclusions Habitat and Fish

• A total of 84 CPM were captured in the Phase II Channel complex and the Reference Channel over the three year study

• CPM were captured in all 8 habitat categories mapped • CPM were also captured in 11 of 18 sample periods (MC and

Reference Channel) • Using the proportion of habitats sampled and capture

habitats, CPM were found in higher numbers in backwaters, embayments and slackwaters and less in runs than expected

• These “preferred” habitats were approximately 30-40% of the

habitat counts in both the Main Channel and Reference Channel

Lessons Learned

• “KISS” Keep it Simple Stupid • “r” vs “k” site selection • Hire Paul Bunyan

• Monitoring Component is vital

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