The Watershed Hydrology Lab will be represented at the AGU Fall Meeting in December in the session on “Groundwater-Surface Water Interactions: Identifying and Integrating Physical, Biological, and Chemical Processes.”
Dynamic Hydraulic Conductivity, Streambed Sediment, and Biogeochemistry Following Stream Restoration
Anne Jefferson, Stuart Baker, and Lauren Kinsman-Costello, Kent State University, Kent, OH, United States
Stream restoration projects strive to improve water quality and degraded habitat, yet restoration projects often fall short of achieving their goals. Hyporheic exchange facilitates biogeochemical interaction which can contribute to positive water quality and habitat, but there are limited data on how restoration affects hyporheic processes. Hyporheic flowpaths can be altered by the processes and products of stream restoration, as well as the transport of fine sediment through the stream bed post-restoration. In two northeastern Ohio headwater streams, variations in hydraulic conductivity and pore water chemistry were monitored following restoration, as measures of hyporheic functioning. A second-order stream restored in August 2013, had a slight decrease in average hydraulic conductivity but an increase in heterogeneity from pre-restoration to four months post-restoration. Data collected 10 and 15 months post-restoration show continued declines in hydraulic conductivity throughout large constructed riffles. These piezometers also indicate dominance of downwelling throughout the riffles with only isolated upwelling locations. Grain size analysis of freeze cores collected in streambed sediments show differences suggesting fluvial transport and sorting have occurred since construction was completed. Pore water sampled from piezometers within the riffles had Mn2+ concentrations ten times higher than surface water, suggesting redox transformations are occurring along hyporheic flowpaths. A first-order stream reach, immediately downstream of a dam, restored in April 2014 had no significant change in average hydraulic conductivity between 1 and 2 months post-restoration, but many individual piezometers had increases of over 100% in high gradient positions or decreases of over 50% in low gradient positions. Changes in hydraulic conductivities in both restored streams are thought to be an adjustments from disturbance to a new dynamic equilibrium influenced by the morphology and sediment regime established by restoration, suggesting these are important processes to consider in the design of such projects.
One of the study streams, 3 months post-restoration.
The Watershed Hydrology lab will be out in force for the Geological Society of America annual meeting in Vancouver in October. For the last few days, we’ve been sharing the abstracts of the work we are presenting there.
AFTER THE DAM COMES DOWN: GROUNDWATER-STREAM INTERACTIONS AND WATER QUALITY EFFECTS OF RESTORED AND UNRESTORED REACHES IN NORTHEASTERN OHIO
BROWN, Krista Marie, Geology, Kent State University, Kent, OH 44240, firstname.lastname@example.org and JEFFERSON, Anne J., Department of Geology, Kent State University, 221 McGilvrey Hall, Kent, OH 44240
Over that past decade, dam removals have become increasingly popular, as many dams near the end of their life expectancy. With an anticipated increase of dam removals in coming years, this study aims to develop an understanding of groundwater-stream interactions and water quality in former reservoirs after dam removal. Low head dams were removed in 2009 on Plum Creek and Kelsey Creek, tributaries to the Cuyahoga River. Kelsey Creek reservoir remains unaltered and consists of a stream channel flowing through riparian-wetland environments, while Plum Creek reservoir underwent channel restoration in 2011. At Kelsey Creek, 20 piezometers and 3 wells were installed within the former reservoir. Since October 2013, hydraulic heads have been recorded semi-weekly for aquifer modeling and water samples have been taken in the wells and stream. Water quality is being evaluated with field-measured parameters and ion chromatography. Plum Creek is being used to understand the water quality effects of channel restoration.
At Kelsey Creek, interaction between the stream and shallow groundwater is evident. The stream tends to contribute shallow groundwater flow toward the western side of the site and north, parallel to the stream. The well closest to the stream shows variability in specific conductance, indicating bidirectional groundwater-stream exchange and all wells show rapid response to precipitation events. Hydraulic conductivity calculated using the Hvorslev method ranged 2.84×10-2to 7.38×10-6 m/s and poorly correlate with the bulk sediments in Kelsey Creek.
Despite the wetland and groundwater-stream exchange in the unrestored Kelsey Creek, there is little change in stream water quality within the former reservoir site, similar to the restored Plum Creek site. This suggests that there is little water quality benefit to be gained from stream restoration at dam removal sites. Left unaltered, Kelsey Creek provides flood control and groundwater recharge in wetland areas.
The Watershed Hydrology lab will be out in force for the Geological Society of America annual meeting in Vancouver in October. Over the next few days, we’ll be sharing the abstracts of the work we are presenting there.
CHANGES IN HYPORHEIC EXCHANGE AND SUBSURFACE PROCESSES FOLLOWING STREAM RESTORATION
BAKER, Stuart B., Department of Geology, Kent State University, 221 McGilvrey Hall, 325 S. Lincoln St, Kent, OH 44242, email@example.com and JEFFERSON, Anne J., Department of Geology, Kent State University, 221 McGilvrey Hall, Kent, OH 44240
Stream restoration is a billion dollar industry with major goals of improving water quality and degraded habitat, yet restoration often falls short of significant improvements in toward these objectives. At present, there are limited data and understanding of the physical and biogeochemical responses to restoration that constrain the potential for water quality and ecological improvements. Hyporheic exchange, the flow of water into and out of the streambed, is an important stream process that serves a critical role in naturally functioning streams, allowing for stream water to interact with the substrate in various processes. Hyporheic flowpaths can be altered by the transport of fine sediment through the stream bed and are thus susceptible to changes in sediment regime and hydraulics, as well as the changes wrought by construction of a restoration project. The goal of this research is to determine the effect of restoration on hyporheic exchange and associated biogeochemical processes. Preliminary results from Kelsey Creek, OH, a second-order stream restored in August 2013, show a slight decrease in average hydraulic conductivity but an increase in heterogeneity from pre-restoration (geometric mean 8.47×10-5 m/s, range 2.67×10-5-3.05×10-4) to four months post-restoration (geometric mean 4.40×10-5 m/s, range 1.18×10-6-1.19×10-3) to ten months post-restoration (geometric mean 1.41×10-5 m/s, range 1.11×10-6-6.40×10-4) in piezometer nests through large constructed riffle structures. These piezometers also indicate dominance of downwelling throughout riffle structures with only isolated locations of upwelling. A stream in Holden Arboretum, OH restored in April 2014 had no significant change in average hydraulic conductivity between 1 and 2 months post-restoration, but many individual piezometers had increases of over 100% or decreases of over 50%. The greater variation in hydraulic conductivities in both restored streams may be adjustment from disturbance to a new dynamic equilibrium. Transient storage and hyporheic exchange were also measured with resazurin injections pre-restoration and post-restoration, and nutrient injections of NH4Cl will compare the nitrogen uptake rates of the restored reach to an unrestored reach downstream.
If you haven’t seen it yet, and you are at all interested in dams and dam removal (or are even wondering why people would be interested in dam removal), I encourage you to watch the film Damnation. The film highlights some of the environmental issues associated with dams, showcases the growing movement to get them removed, and shows us the results when dams do come out. Plus, it features gorgeous scenery of Pacific Northwest Rivers. So check out the screening in Cleveland this week (info below) or ask Anne how to get access to her copy of the film.
Here’s the trailer:
The award-winning documentary, Damnation, is coming to Cleveland’s Capitol Theater on Wednesday, September 24th at 7 p.m. The movie tells the story of the use of dams around the United States and the impact that dams have on rivers. It was produced by Yvon Chouinard who, among many other conservation accolades, is the founder of Patagonia.
Kdudley Media is hosting the presentation of the movie at the Capitol and they have graciously invited Friends of the Crooked River to be their special guest. FOCR will have an informational display in the lobby before the showing and have a Q&A session after the movie focusing on local dam removal efforts. In addition, Kdudley has decided to donate any funds raised from the showing of the movie to FOCR in support of our conservation efforts. Here is a link to more information about the film: www.damnationfilm.com
Tickets will be available at the door, as well as on line.
The Capitol Theater is located at W. 65th and Detroit in Cleveland’s District, Gordon Square District. This area is also home to several good restaurants ranging from casual to upscale so you may want to come early and make a night of it.
Hope to see you on September 24th
Social Hour at 6 PM
Film at 7 PM
Q&A concerning dams on the Cuyahoga following show
Collaborator Jason Vogel at Oklahoma State asked me to spread the word about their cool new REU on stream restoration, starting this summer. Application deadlines are February 15th and the program runs May 26 – July 31st. For more information: http://studentwater.okstate.edu/content/nsf-reu-streams
A Research Experience for Undergraduates (REU) Site will provide seven undergraduate students a research experience over a ten week period during the summers of 2015-2017. The research will include studies in hydrology, geosciences, and biology at the Cow Creek Stream Rehabilitation Site on the Oklahoma State University (OSU) campus. The opportunity to study streams at a site on a University campus recently rehabilitated is unique. The central theme of the program will be discussing ways to rehabilitate streams, and specifically evaluating natural channel design approaches through process-based investigations. Billions of dollars are spent annually on stream rehabilitation across the United States. Many current stream rehabilitation projects use natural channel design concepts, which are often criticized. The alternative is a complex, process-based analysis of the dynamic system and impact of stream modifications on the hydraulics, sediment transport, and biological community. This proposal hypothesizes that future restoration approaches will most likely resemble a morphed combination of natural channel design and process-based techniques. Students will participate in research projects quantifying the role of vegetation on streambank erosion, documenting the influence of in-stream structures on retention in the stream, evaluating the effect of sediment on fish, using aquatic macroinvertebrates to assess streambank modifications, evaluating plant diversity response, and studying vegetation impacts on stream temperature.
I participated in this a few years ago and it was a great experience for practitioners, regulators, and academics of stream restoration.
Let me encourage you to submit an abstract to the 2015 Upper Midwest Stream Restoration Symposium (UMSRS) to be held Feb 8-11, 2015 in Dubuque, Iowa. Organized by the regional Partnership for River Restoration and Science in the Upper Midwest (PRRSUM), the UMSRS focuses on bringing together researchers and applied practitioners to advance the dialogue of river and stream restoration in the Midwest.
The oral abstract deadline for the conference is September 26, 2014. Learn more in the attached flyer and PRRSUM brochure. If you are unable to participate, please consider signing up for our mailing list to learn about other PRRSUM activities (only 1-2 emails a month!) at www.prrsum.org.
For more information: http://www.prrsum.org/
Next week, the Watershed Hydrology Lab will be well represented at the CUAHSI 2014 Biennial Colloquium. We’ll be presenting four posters, so here come the abstracts…
Development of hyporheic exchange and nutrient uptake following stream restoration
Stuart Baker and Anne Jefferson
Stream restoration is a multi-million dollar industry in Ohio, with major goals of improving water quality and degraded habitat. Yet restoration often falls short of significant improvements in water quality and biodiversity. It is thus important to improve the theory and practice of stream restoration in order to achieve greater benefits per dollar spent, yet there are limited data and understanding of the physical and biogeochemical responses to restoration that constrain the potential for water quality and ecological improvements. Hyporheic exchange, the flow of water into and out of the streambed, is an important stream process that serves critical roles in naturally functioning streams, allowing for stream water to participate with the substrate in various processes. Hyporheic flowpaths can be altered by the transport of fine sediment through the stream bed and are thus susceptible to changes in sediment regime and hydraulics, as well as the changes wrought by construction of a restoration project. The goal of this research is to determine the effectiveness of restoration in enhancing hyporheic flow and associated biogeochemical processes to improve water quality. Preliminary results from Kelsey Creek, OH, a second-order stream restored in August 2013, show a decrease in average hydraulic conductivity but an increase in heterogeneity from pre-restoration (geometric mean 8.47×10-5 m/s, range 1.18×10-6-1.19×10-3) to post-restoration (geometric mean 4.41×10-5 m/s, range 2.67×10-5-3.05×10-4) in piezometer nests through large constructed riffle structures. These piezometers also indicate dominance of downwelling throughout riffle structures with only isolated locations of upwelling. Transient storage and hyporheic exchange will be measured with resazurin injections for comparison between pre-restoration and post-restoration, and nutrient injections of NH4Cl at time points following the restoration will compare the nitrogen uptake rates of the restored reach to an unrestored reach downstream. Additional sites are planned for study to include restoration projects of different ages to examine the development of hyporheic exchange and biogeochemistry after completion of restoration projects.
Next week, the Watershed Hydrology Lab will be well represented at the CUAHSI 2014 Biennial Colloquium. We’ll be presenting four posters, so here come the abstracts…
After the dam comes out: groundwater-stream interactions and water quality impacts of former reservoir sites
Krista Brown and Anne Jefferson
Over that past decade, dam removals have become increasingly popular, as many dams near the end of their life expectancy. With an increasing number of anticipated dam removals coming in the near future this study aims to develop an understanding of groundwater-stream interactions and water quality in former reservoir sites after dam removals have occurred. Low head dams (~2 m) were removed in 2009 from Plum Creek in Kent, Portage County, Ohio and on Kelsey Creek in Cuyahoga Falls, Summit County, Ohio. Kelsey Creek reservoir has been unaltered since the dam removal and consists of a stream channel flowing through riparian- wetland environments, while Plum Creek reservoir underwent channel restoration in 2011. At Kelsey Creek, 20 piezometers and 3 wells were installed in the stream and riparian areas. Pressure transducers were also deployed in each well and stream from November 20, 2013 to January 5, 2014. Hydraulic conductivity was calculated using the Hvorslev method. Since October 2013, hydraulic heads have been recorded semi-weekly and water samples have been taken in the wells and stream. Water quality is being evaluated with field-measured pH, temperature, specific conductance, and dissolved oxygen, and ion chromatography of chloride, bromide, nitrate, sulfate and phosphate concentrations. Plum Creek is being used to understand the water quality effects of channel restoration at former reservoir sites.
At Kelsey Creek, hydraulic conductivity ranges five magnitudes, from 10?2 to 10?6 m/s, but wells near the channel, in an off-channel wetland, and on an adjacent hillslope respond similarly during high flow events. However, the well closest to the stream shows substantial variability in specific conductance, indicating bidirectional groundwater-stream exchange. Despite the wetlands and presumed greater groundwater-stream exchange in the unrestored Kelsey Creek, stream water quality is similar to the restored Plum Creek site. This suggests that the water quality measures considered here should not determine whether to restore channels within former reservoir sites. Findings from this research may be applicable when considering options for future dam removal sites.
Cross-posted at Highly Allochthonous
This summer we were treated to not one but two dam removals on the Cuyahoga River, ~10 miles downstream from Kent. Those following me on twitter know that I obsessed about these removals all summer long, first as they were delayed by weeks of high water, then as they got started and I got to watch first on the live “dam cam” and then in person. But the video compresses a whole summer of waiting, watching, and obsessing into two and a half glorious minutes, complete with music. This is, without a doubt, what youtube was invented for.*
If that dam removal video merely served to whet your appetite for dam busting, I have a few other videos you might enjoy. First, there’s there’s an excellent 8 minute documentary on Marmot Dam on the Sandy River, Oregon, which explains the science that led up to this removal, features the excitable Gordon Grant, and shows the action unfolding. If you just want to cut to the action, you can’t beat the “blow and go” (that would be the technical term) of the Condit Dam removal in Washington. Finally, a feature length movie called DamNation is coming our way in 2014. I’m so excited, I can hardly stand it. I’m going to go watch the videos a few more times.
*Youtube was also invented for flash flood videos, videos of people running rapids on the Grand Canyon, the Lake Peigneur disaster video, and corny videos produced by sewer districts about CSOs.
Abstract season is upon us. I’ll be at AGU, where there looks to be loads of good sessions, including one on “Groundwater-Surface Water Interactions: Physical, biological, and chemical relevance“. Hopefully, my work (abstracted below) will be part of this session.
Transient Storage versus Hyporheic Exchange in Low-gradient Headwater Streams
A.J. Jefferson, S.M. Clinton, M. Osypian
In-channel storage and hyporheic exchange are components of transient storage that exist as a function of geomorphology and which can have contrasting effects on nutrient retention, temperature, and biological communities. In order to evaluate and predict the effects of geomorphic changes on the biogeochemical and ecological functioning of transient storage zones, in-channel storage needs to be quantified separately from hyporheic exchange. In four headwater streams, we used salt injections modeled in OTIS-P to quantify total transient storage fluxes and piezometer measurements to quantify hyporheic fluxes. In the mixed bedrock-alluvial streams, restoration increased both in-channel and hyporheic exchange fluxes, but in-channel transient storage was dominant. In the fully alluvial streams, total transient storage fluxes were ~100 times greater in the stream which had undergone restoration than in one where no restoration had occurred. Conversely, hyporheic fluxes were ~400 times smaller in the restored alluvial stream. Thus, in the restored stream, hyporheic flux was <1% of total transient storage flux, while in the unrestored stream, hyporheic flux accounted for up to 75% of total transient storage fluxes. This difference in the contribution of the hyporheic zone to total transient storage appears to be a function of both channel morphology and bed sediments, primarily the creation of pools and reduction in sediment size that occurred as a result of restoration. These dramatic variations in the magnitude and relative proportions of in-channel and hyporheic fluxes that occur across low-gradient, headwater streams may be an important control on reach-scale biogeochemical and ecosystem functioning.