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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.
Leaving behind Ohio and the high waters from Sandy, I ventured south in early November for the Geological Society of America meeting in my former home of Charlotte, North Carolina. The meeting was busy and wonderful, and far too packed for me to hear as much science or talk to as many people as I would have wished. After the meeting was over, I stuck around Charlotte for a few days in order to do some field work with one of my graduate students. Our plan was to do a tracer injection in one of the headwater streams that form her field area. Such tracer injections are a bit finicky to schedule…if it’s raining or has recently rained, you can’t do them because the stream discharge won’t be steady over the several hours of the experiment. But Sandy had not dropped any rain on the Charlotte area and the weather was beautiful all during the conference. Nonetheless, my student assured me that there would be plenty of water in the stream, as it had been running well just two weeks prior. Perfect conditions, we thought.
So the afternoon before the experiment, we headed out to the study site to measure discharge and mark the places where we would be collecting samples. My student advised me to wear my hip waders, not knee boots, as she had over topped her boots last time she was in the field.
But…it turns we didn’t need the boots. At all.
Clearly, we could not add our tracer to the streamflow the next day. We were missing one crucial ingredient: streamflow.
One upside to the situation is that it was a very easy call to make. No hemming and hawing and making some sort of judgement about whether things were “good enough” to go for it. We simply couldn’t do the experiment.
It was also stunningly good conditions for walking the channel and looking at the location and conditions of the stream restoration structures and wood jams. And we spent the next day with our heads together working on much more solid plans for the eventual experiment. So, not a total loss.
But now we need to wait, for the right hydrological conditions, suitable ecology, and a time that works in our schedules. Field work is incredibly important for learning about the way that real, complex hydrologic systems work. And it can be incredibly fun. But it can also be filled with frustration…and waiting. In this case, for the “right conditions for a stream tracer injection.”
EVALUATING RESTORATION EFFECTS ON TRANSIENT STORAGE AND HYPORHEIC EXCHANGE IN URBAN AND FORESTED STREAMS
OSYPIAN, Mackenzie L., Civil Engineering, University of North Carolina at Charlotte, Charlotte, NC 28262, firstname.lastname@example.org, JEFFERSON, Anne J., Department of Geology, Kent State University, 221 McGilvrey Hall, Kent, OH 44240, and CLINTON, Sandra, Department of Geography and Earth Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223
Millions of dollars are spent each year on restoration projects designed to improve stream habitat, but few studies have investigated effects of restoration on hyporheic exchange and transient storage. Stream water-groundwater interactions and transient storage in four second-order streams (urban/forest; restored/urestored) were studied by measuring geomorphology, streambed vertical head gradients and water fluxes, and by using conservative, impulse-loaded tracer studies along with the OTIS model. The magnitude of upwelling and down welling was observed to be greatest in the restored urban stream, which contains large step structures, while the smallest gradients were observed in the unrestored urban stream, which is incised to bedrock. OTIS results show that the 120 m unrestored urban reach with a debris dam has an average transient storage of 1.8×10^-2 m2/m and an ? of 9.5×10^-4 s^-1 while a 55m restored forested reach with log sills has an average transient storage of 8.3×10^-2 m2/m and an ? of 1.5×10^-4 s^-1. Based on these results, we conclude that restoration changes transient storage metrics, and ongoing work aims to understand how these changes affect ecosystem health.
Some of our students are in the field this week, injecting Cl- and Br- into a restored reach and an unrestored reach in tributaries of Beaver Dam Creek. Our goal is to understand the role of wood jams versus restoration structures in promoting stream-hyporheic exchange.
In the photo are Alea, Xueying, and Mackenzie. Photo by Brittany. They’ve got it so capably handled they didn’t even need Sandra or I out there with them today, but I’m going tomorrow for an excuse to be in the field as much as anything.
Major congratulations to two Watershed Hydrogeology Lab graduate students who have finished writing their MS theses and will defend them next week. Ralph McGee and Cameron Moore both started in our MS in Earth Science program in August 2009, and less than two years later they have each completed impressive MS projects on headwater streams in Redlair Forest of the North Carolina Piedmont.
Ralph McGee will present his research on “Hydrogeomorphic processes influencing ephemeral streams in forested watersheds of the southeastern Piedmont U.S.A.” on Thursday, May 12th at 10:00 am in McEniry Hall, room 111 on the UNC Charlotte campus.
The unofficial title for Ralph’s work is “Tiny Torrents Tell Tall Tales.” Watch the video below to see why.
Cameron Moore will present his research on “Surface/Groundwater Interactions and Sediment Characteristics of Headwater Streams in the Piedmont of North Carolina” on Friday, May 13th at 9:00 am in McEniry Hall, room 111 on the UNC Charlotte campus.
When Cameron started working on this project, I had thought that the story would focus on how fractured bedrock contributed to groundwater upwelling in the streams, but it turns out the small debris jams (like the one below) are the dominant driver of groundwater/stream interactions and spatial variability of channel morphology.
Faculty, students, and the public are encouraged to attend the presentations and ask Ralph and Cameron any questions they may have.
This post is cross-posted at Highly Allochthonous. Please look over there for any comments.
Last week was the Geological Society of America meeting in Portland, Oregon. Just below is a view of Mt. Hood looking from the north, which I might have seen if I were not busy in and around the convention center the entire time. What follows are some brief notes from my activities on Monday and Tuesday of the conference.
On Monday morning, I attended a couple of talks and browsed the deserted poster aisles, since I knew I would be in a session all afternoon and unable to attend the designated poster time. Of the talks I attended, the one that sticks most in my mind was one by Karen Gran, who opened with an eloquent argument for why geomorphologists should care about the landscape evolution of very flat places, in her case, the Le Sueur River in southern Minnesota. Here the sudden base level drop triggered by the draining of Lake Agassiz down the Minnesota-Mississippi River system has triggered 11,000 years of knickpoint retreat and bank erosion that has been exacerbated by modern agricultural practices, such as tile drainage.
Monday afternoon I helped convene a session on “Stream-Groundwater Interaction: New Understanding, Innovations, and Applications at Bedform, Reach, and River Network Scales” sponsored by the Hydrogeology division. We had a great line-up of speakers, from undergraduate to professor, that are actively pushing our understanding of how streams and groundwater interact in environments from the hydropower-generating diurnally-fluctuating Colorado River in Austin, Texas (Bayani Cardenas, Katelyn Gerecht) to the possibility of modern recharge to the Great Artesian Basin in the center of Australia (Brad Wolaver working on the Finke River). We heard about a new smart tracer for quantifying the metabolically active transient storage (Roy Haggerty), radium as a tracer of groundwater inputs to the Sea of Galillee and North Carolina’s Neuse River (Hadas Ranan), electrical resistivity for mapping saline upwelling in Nebraska wetlands (Ed Harvey), and lots about using temperature as a tracer of groundwater-stream interactions (John Selker, Christine Hatch, Laura Lautz, Jeannie Barlow). We contemplate the effects of our common simplifying steady-state assumptions (Jesus Gomez) and marveled over a flume and numerical investigation of hyporheic exchange caused by a simple log (Audrey Sawyer). The questions from the audience were provocative and the conversations during our breaks were enjoyable and stimulating. It was my first time chairing a session, and I couldn’t have been more pleased with the day it turned out.
Monday evening brought the usual round of alumni receptions and the geoblogger/tweeter meet-up. Much has been said about that elsewhere, but I’ll add that I greatly enjoyed making the acquaintance of so many interesting people and renewing my friendship with others. There were definitely a couple of small-world moments over the course of the evening, and I’ll hazard that it was the largest geoblogger/tweeter meetup on record. Shall we aim to break the record next year?
On Tuesday, I did not go to a single talk. There are no geomorphology sessions on Tuesday because of the Kirk Bryan field trip, and the hydrogeologists have no oral sessions because of their afternoon banquet. So I spent the morning over a wonderful breakfast with wonderful friends and attended the hydrogeology banquet almost immediately thereafter. In the late afternoon, I presented my poster and missed Kim’s talk and then meandered my way over to the Quaternary Geology and Geomorphology (QG&G) award ceremony and mixer.
Please don’t ask me to say who knows how to have more fun: the hydrogeologists or geomorphologists. All I’ll say is that singing was involved at one event and very clever photoshopping at another. At least one set of geologists believe it is perfect acceptable to receive a major professional award while wearing jeans and holding a beer.
For me, the single best highlight of the entire week was talking to Reds Wolman, my academic grandfather and undergraduate geomorphology professor. Reds is an amazing teacher, magnificent scientific mind, and a caring person who mentored many of the leading geomorphologists of the last half century. Though he’s gotten to be quite elderly, he attended much of the meeting and I got the chance to chat with him and hear his stories several times. I’ll also got to hear a very nice, if cheeky, tribute to him by Reds’ former student, John Costa, who was awarded the QG&G distinguished career award.
In my next post, I’ll finish out the meeting by talking about what happens when it rains a lot about this time of year and the mountains fall down. Plus, I’ll show some pictures of really big rocks.
This post is cross-posted at Highly Allochthonous. Please look over there for any comments.
Haggerty, Roy; Martí, Eugènia; Argerich, Alba; von Schiller, Daniel; Grimm, Nancy B. 2009. Resazurin as a “smart” tracer for quantifying metabolically active transient storage in stream ecosystems J. Geophys. Res., Vol. 114, No. G3, G03014
(Roy will be talking about this work in our session at the GSA Annual Meeting next month.)
Harman, C. J.; Sivapalan, M.; Kumar, P. 2009. Power law catchment-scale recessions arising from heterogeneous linear small-scale dynamics Water Resour. Res., Vol. 45, No. 9, W09404
(Ooh, this sounds really cool. I’ve been interested in heterogeneity in watersheds for a while, and this looks like an interesting take on the topic.)
Moussa, Roger 2009. Definition of new equivalent indices of Horton-Strahler ratios for the derivation of the Geomorphological Instantaneous Unit Hydrograph Water Resour. Res., Vol. 45, No. 9, W09406
Philip Brunner, Craig T. Simmons, Peter G. Cook
Spatial and temporal aspects of the transition from connection to disconnection between rivers, lakes and groundwater
Journal of Hydrology, 376: 159-169
Astrid Lambrecht, Christoph Mayer, 2009, Temporal variability of the non-steady contribution from glaciers to water discharge in western Austria, Journal of Hydrology, 376: 353-361.
(Relevant to my Mt. Hood work.)
I. P. Holman, M. Rivas-Casado, N. J. K. Howden, J. P. Bloomfield, A. T. Williams. 2009. Linking North Atlantic ocean-atmosphere teleconnection patterns and hydrogeological responses in temperate groundwater systems. Hydrologic Processes. 23(21): 3123-3126.
(The invited commentaries (like this one) in HydroPro are almost always worth a read to see what leading hydrologic thinkers are thinking about.)
Tiwari, V. M.; Wahr, J.; Swenson, S. 2009. Dwindling groundwater resources in northern India, from satellite gravity observations Geophys. Res. Lett., Vol. 36, No. 18, L18401
(This is at least the third paper I’ve seen on this topic in the past month. It is big big news.)
The Watershed Hydrogeology Lab is going to be busy at this year’s Geological Society of America annual meeting in Portland, Oregon in October. We’ve submitted four abstracts for the meeting, I am co-convening a session, and I’ll be helping lead a pre-meeting field trip.
The abstract below pulls together some of the work that Cameron More and I have been doing at Redlair, along with similar work by the NC Division of Water Quality at the Allison Woods and Bent Creek research sites. I’m quite hopeful that the work summarized here will be expanded by Cameron for his MS thesis.
Groundwater contributions to headwater streams on fractured rock in the North Carolina Piedmont and Blue Ridge
Anne Jefferson, Department of Geography and Earth Sciences, University of North Carolina at Charlotte, 9201 University City Boulevard, Charlotte, NC 28223
Joju Abraham, North Carolina Division of Water Quality, Aquifer Protection Section, 610 E Center Ave, Mooresville, NC 28115
Ted Campbell, North Carolina Division of Water Quality, 2090 Highway 70, Swannanoa, NC 28778
Cameron Moore, Department of Geography and Earth Sciences, University of North Carolina at Charlotte, 9201 University City Boulevard, Charlotte, NC 28223
Baseflow is generally assumed to homogenously accrete into headwater channels through flow from soil and porous bedrock, but on crystalline rocks there may be discrete up-welling and down-welling zones associated with fractures. Despite the prevalence of fractured crystalline rocks in the Appalachians and Piedmont of the eastern United States, little work has been done to document and understand groundwater-stream interactions in fractured rock environments.
At three sites in the North Carolina Piedmont and Blue Ridge provinces, groundwater and first-order streams were monitored for temporal and longitudinal temperature and water quality patterns. Stream temperatures at all sites have strong diurnal and seasonal fluctuations, while streambed sediments show smaller diurnal variability. Near-stream piezometers and wells show no diurnal temperature fluctuations, and seasonal fluctuations lag air temperature changes by 1-7 months or are absent. These lags generally increase with depth. In response to rainfall events, a shallow well in a discharge zone at one site (Bent Creek) showed temperature perturbations within 18-20 hours, suggesting upwelling from deeper flow zones. At another site (Allison Woods), rainfall perturbed groundwater temperatures in piezometers screened 1-2.4 m below land surface, but not in wells screened 2.1-7 m below land surface, suggesting groundwater recharge. There is a general trend towards downstream heating in the summer, but several temperature probes deviate from this trend, and synoptic surveys show that some areas with depressed temperatures have elevated specific conductance. These results suggest that there are distinct groundwater upwelling areas within the streambed. At one site (Deep Creek), seasonal variation in stream water isotopes suggest that baseflow is sourced in water <5 years old.
Some streams also have ephemeral reaches that correspond with debris jams and sediment wedges, where all baseflow infiltrates into the stream bed. In other reaches, the streams flow on bedrock with fine alluvium banks and hyporheic exchange may be quite limited. Ongoing work aims to understand the relative importance of hyporheic exchange versus fracture systems in setting the patterns of groundwater-surface water interactions in Piedmont and Blue Ridge headwater streams.
Fiorillo, F. 2009. Spring hydrographs as indicators of droughts in a karst environment. Journal of Hydrology 373: 290-301.
Rosenberry, D.O. and J. Pitlick. 2009. Effects of sediment transport and seepage direction on hydraulic properties at the sediment–water interface of hyporheic settings. Journal of Hydrology 373: 377-391.
Gresswell, R. et al. 2009. The design and application of an inexpensive pressure monitoring system for shallow water level measurement, tensiometry and piezometry. Journal of Hydrology 373: 416-425.
Fryar, A.E. 2009. Springs and the Origin of Bourbon [Historical Note], Ground Water, 47(4): 605-610.
Cardenas, M. Bayani. 2009. Stream-aquifer interactions and hyporheic exchange in gaining and losing sinuous streams Water Resour. Res., Vol. 45, No. 6, W06429
Selker, John; Ferre, Ty P. A. 2009. The ah ha moment of measurement: Introduction to the special section on Hydrologic Measurement Methods Water Resour. Res., Vol. 45, No. null, W00D00
Hodgkins, Glenn A. 2009. Streamflow changes in Alaska between the cool phase (1947-1976) and the warm phase (1977-2006) of the Pacific Decadal Oscillation: The influence of glaciers Water Resour. Res., Vol. 45, No. 6, W06502
Matott, L. Shawn; Babendreier, Justin E.; Purucker, S. Thomas Evaluating uncertainty in integrated environmental models: A review of concepts and tools Water Resour. Res., Vol. 45, No. 6, W06421
Orr, Cailin H.; Clark, Jeffery J.; Wilcock, Peter R.; Finlay, Jacques C.; Doyle, Martin W. Comparison of morphological and biological control of exchange with transient storage zones in a field-scale flume J. Geophys. Res., Vol. 114, No. G2, G02019
Katsuyama, Masanori; Kabeya, Naoki; Ohte, Nobuhito Elucidation of the relationship between geographic and time sources of stream water using a tracer approach in a headwater catchment Water Resour. Res., Vol. 45, No. 6, W06414
Phillips, J.D. 2009. Landscape evolution space and the relative importance of geomorphic processes and controls. Geomorphology, 109:79-85.
And last but not least:
Pretty much all of: Hydrological Processes, Special Issue: Hyporheic Hydrology: Interactions at the Groundwater-Surface Water Interface. Issue Edited by Stefan Krause, David M. Hannah, Jan H. Fleckenstein. Volume 23, Issue 15, 2009.
Most especially this article:
Boano, F., Revelli, R., and Ridolfi, L. 2009. Quantifying the impact of groundwater discharge on the surface-subsurface exchange, Hydrological Processes, 23(15): 2108-2116.