Chiloquin Dam Removal Monitoring Update – Vol I
This update of monitoring of the Chiloquin dam removal is intended to help the various actors involved know the status of each other’s research. As it is a first iteration we (OSU – contact: ) welcome feedback such as: what information to include in the next iteration?, how often to provide these updates?, how can this be a more useful document for all involved?
In the interest of facilitating communication and the sharing of information, OSU has developed a website and a dam monitoring data library: The goal for the data library is to provide a forum for making monitoring data easily available and digestible. The library is currently set up as an interface with Google Earth™. The Chiloquin monitoring map prepared by USBR was used as a starting point, and expanded within GE. Currently the majority of detail can be seen in the data collected by OSU in 2008. However this is only a starting pointand we look forward to expanding the amount of data available through the site, adding new details and incorporating feedback. The data library is offered on the above site as a zipped folder containing a file called “Chiloquin_Data_Library.kmz”. Once extracted, the .kmz file can be opened using Google Earth. Due to file size constraint, datasets with over 5000 or so data points could not be displayed (USBR acoustic Doppler surveys of both the reservoir and river).
United States Bureau of Reclamation
Recent work:
August 2008: Time lapse photography was taken during the deconstruction of Chiloquin Dam. Both low and high resolution versions can be seen at:
September 2008: Bathymetry and sediment surveys were taken to compare with pre-removal surveys. The survey reach extended past the highway 97 bridge to Upper Klamath Lake. Preliminary results show that sediment from the former reservoir has filled the pool directly below the dam site, but no significant deposition downstream of this pool has occurred. Sediment remaining within the active channel is contained in a pool extending upstream from the power lines, with a depth of ~1-2 feet.
October 2008: Low elevation aerial photography (via helium filled balloon) was performed to map the position of logs impounded in the former reservoir. The photos were used to create orthophotos of the reservoir, which were used to identify and digitize over 1400 logs in the first ½ mile above the dam site. A cross sectional survey of the reservoir was performed. Data can be obtained from Travis Bauer(, 303-445-3672).
Planned work:
June 2009: If spring high flows mobilize sediment, USBR will repeat bathymetry, sediment sampling, and balloon mounted aerial photography completed in 2008.
Science/management questions of interest:
-How will sediment stored behind Chiloquin Dam move and be deposited? (And how does this correspond to modeled predictions of sediment movement and deposition?)
-How will large wood impounded in the former reservoir move?
-How will fish respond to the removal in terms of adult migration and spawning as well as larval/juvenile outmigration success?
The Klamath Tribes
Recent work:
Spring 2009: The Klamath Tribes are supporting ongoing efforts in monitoring SSC including sampling USGS gauge sites 1150100 (Sprague above Chiloquin), 11502500 (Williamson below Sprague confluence). They have coordinated simultaneous SSC samples at Kircher’s bridge and the Williamson upstream of the confluence in conjunction with SSC sampling by the USGS at these two gauging stations to assist with identification of a suspended sediment signal emanating from the former reservoir. Between 1/6/09 and 4/6/09, seven SSC samples have been collected at both of the above gauges
Planned work:
Late spring and summer 2009: Continue taking SSC samples in coordination with USGS. Dam removal monitoring is a small piece of the attempt to produce a basin wide geomorphic monitoring plan for the Sprague basin. The Klamath tribes will be processing SSC samples at their water quality monitoring lab.
US Fish and Wildlife Service
Recent work:
USFWS has been monitoring juvenile fish emigration on the Sprague and Williamson rivers for the past 3 years. More detailed information on the results of this monitoring will be available soon (contact: ). USFWS also collected EMAP physical habitat and fish data on the Sprague River in 2008.
Planned work:
Due to program changes and lack of funding, these efforts will not continue in 2009.
USGS
Recent work:
2008: Continuous turbidity probes were installed in November 2007 at 2 gauges:
1150100 (Sprague above Chiloquin) and 11502500 (Williamson below Sprague)
SSC measurements were taken throughout 2008 and early 2009 to facilitate the development of SSC/turbidity rating curves.
5 PIT tag arrays (2 in the Williamson and 3 in the Sprague) are being maintained by USGS. Monitoring of larval drift is occurring at 6 sites (1 on the Williamson, 4 on the Sprague, and 1 on the Sycan). Funding for this work was provided mainly by USBR, with USGS funding the remainder. Walt Duffy with the USGS Coop Unit at Humboldt State University has ongoing projects investigating larval rearing habitats in the Sprague River Valley.
Planned work:
Early Spring 2009: Continued maintenance of turbidity meter at gauges and continued SSC samples. Monitoring of PIT tag arrays and larval drift monitoring will continue.
Continued SSC sampling work in coordination with OSU and the Klamath Tribes.
OSU
Recent work:
August/September 2008: Surveyed 4 cross sections in each of 9 riffles (4 in Williamson below the confluence, 2 in Sprague below dam site and 3 upstream of the reservoir). Also surveyed10 monumented cross sections in the former reservoir and the extent of all bars within the riffles. Pebble counts were taken at all cross sections. The intent is to characterize sediment deposition and change in surface sediment size distribution in bars and riffles to supplement the information on deposition in pools from the USBR bathymetry surveys. Habitat and invertebrate information was collected using the EPA’s EMAP protocols in the Williamson betweenthe confluence and the Hwy 97 bridge, with help from John Hodge of USFWS.
Fall 2008/Winter 2009: Helping to coordinate SSC sampling and the development of SSC/turbidity rating curves. Set up 9 photo points on the lower Sprague, mostly in and around the reservoir, to obtain documentation of wood and sediment movement as well as vegetation changes.
Planned work:
Summer 2009: Repeat all surveys, pebble counts, habitat and invertebrate samples.
Survey of the major species and extent of vegetation recolonizing the former reservoir. Website
development will continue.
Science/management questions of interest:
-Does movement of wood correspond to spikes in SSC/turbidity?
-Does deposition occur primarily in pools and does it affect holding habitat?
-Does grain size of potential redband trout spawning habitat (mainly riffles) change with
removal? If so, how far downstream?
-Does hydraulic habitat complexity in the channel increase in the Sprague down to theconfluence? (use field data to inform 2D modeling) And for how long?
-Does invertebrate community (composition, density, functional traits) shift one year following dam removal? After two years? If so, is invertebrate community change related to changes in GSD of riffles? To changes in reach‐wide habitat conditions?
-Is a substantial change in periphtyon (biomass, Chl A, composition) observed one year followingremoval?
- Where does vegetation establish in the reservoir and which species are primary colonizers?
-Does location of eroded reservoir sediment correspond to areas of unvegetated sediment? Todistribution of species?