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watershed hydrology

The 2016 Kent State Water and Land Symposium

A major focus for the Watershed Hydrology lab this fall has been preparing for the Kent State University Water and Land Symposium. Anne Jefferson was the symposium co-chair (with lots of help from Biology’s Chris Blackwood), and all of the lab members were involved in some way. Pedro, Laura, Hayley, and Cody presented posters. Caytie and Garrett helped with set up and were on tweeting duty. The symposium had about 400 attendees from universities, agencies, cities, non-profits, and the general public from throughout northeast Ohio. If you missed the event live or on twitter, here’s how it went down.

 

This year’s symposium occurred on October 5-6, 2016, and featured the theme of “Sustainability and Resilience on the Land-Water Continuum.”

How low will they go? The response of headwater streams in the Oregon Cascades to the 2015 drought

From a distance, Anne has been watching an incredibly unusual summer play out in the Pacific Northwest, following a winter with far less snow (but more rain) than usual. Folks on the ground in Oregon have been collecting data on the response of the Oregon Cascades streams to “no snow, low flow” conditions. Anne is making minor contributions to the following poster, to be presented in Session No. 291, Geomorphology and Quaternary Geology (Posters) at Booth# 101 on Wednesday, 4 November 2015: 9:00 AM-6:30 PM.

HOW LOW WILL THEY GO? THE RESPONSE OF HEADWATER STREAMS IN THE OREGON CASCADES TO THE 2015 DROUGHT

LEWIS, Sarah L.1, GRANT, Gordon E.2, NOLIN, Anne W.1, HEMPEL, Laura A.1, JEFFERSON, Anne J.3 and SELKER, John S.4, (1)College of Earth Ocean and Atmospheric Sciences, Oregon State University, Corvallis, OR 97331, (2)Pacific Northwest Research Station, USDA Forest Service, 3200 SW Jefferson Way, Corvallis, OR 97331-8550, (3)Department of Geology, Kent State University, Kent, OH 44242, (4)Biological & Ecological Engineering, Oregon State University, Corvallis, OR 97331, sarah.lewis@oregonstate.edu

Larger rivers draining the Oregon Cascades are sourced from headwater systems with two distinct runoff regimes: surface-flow dominated watersheds with flashy hydrographs, rapid baseflow recession, and very low summer flows; and spring-fed systems, with slow-responding hydrographs, long baseflow recession, and summer flow sustained by deep groundwater fed coldwater springs. Our previous research has explored these differences on both the wet west-side and dry east-side of the Cascade crest, as expressed in contrasting discharge and temperature regimes, drainage efficiency, low and peak flow dynamics, and sensitivity to snowpack and climate change scenarios. In 2015, record low winter snowpack combined with an anomalously dry spring resulted in historically low flows across our research sites and throughout Oregon. These extreme meteorological conditions, equivalent to a 4°C warming scenario, offer an exceptional opportunity to witness how these contrasting stream networks might respond to anticipated changes in amount and timing of recharge.
Conceptually, channel network response to decreasing discharge may involve both lateral and longitudinal contraction. Lateral contraction, the decrease of wetted channel width and depth, occurs in both surface-flow and spring-fed streams as flows diminish. Longitudinal contraction may be expressed as (a) a gradual drying of the stream channel and downstream retreat of the channel head, (b) a “jump” of the channel head downstream to the next spring when an upper spring goes dry, or (c) no change in channel head despite diminishing flows. We hypothesize that while individual stream channels may display a combination of these dynamics, surface-flow and spring-fed watersheds will have distinctive and different behaviors. We field test our hypothesis by monitoring channel head locations in 6 watersheds during the low flow recession of 2015, and repeatedly measuring discharge, water quality and hydraulic geometry at a longitudinal array of sites along each surface-flow or spring-fed channel. The resulting data set can be used to explore the fundamental processes by which drainage networks accommodate decreasing flows.

Hydrologic response to watershed metrics describing urban development and mitigation with stormwater control measures

Watershed Hydrology lab collaborator and Ph.D. candidate Colin Bell will be giving a talk in T106. From Green Roofs and Gutters to Urban Streams: Advancing Urban Watershed Hydrology through Innovative Field and Modeling Approaches on Monday, 2 November 2015 at 2:25 pm in Room 342 (Baltimore Convention Center).

HYDROLOGIC RESPONSE TO WATERSHED METRICS DESCRIBING URBAN DEVELOPMENT AND MITIGATION WITH STORMWATER CONTROL MEASURES

BELL, Colin D., Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907, MCMILLAN, Sara K., Agricultural and Biological Engineering, Purdue University, West Lafayette, IN 47907-2093, JEFFERSON, Anne J., Department of Geology, Kent State University, Kent, OH 44242 and CLINTON, Sandra, Department of Geography and Earth Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223, bell137@purdue.edu

Stormwater control measures (SCMs) are designed to mitigate changes in hydrologic response to hydrometeorological forcing caused by urban development. Total imperviousness (TI) is a metric that effectively quantifies this urban development, but does not contain information about the extent of SCM mitigation within the watershed. The hydrologic records of 16 urban watersheds in Charlotte, NC spanning a range of TI (4.1 to 54%) and mitigation with SCMs (1.3% to 89%) were analyzed to identify which of a suite of easily-determined watershed metrics best predict hydrologic behavior. We tested the watershed metrics TI, percent forested coverage, impervious area unmitigated by SCMs, effective impervious area, percent SCM-mitigated area, and a newly-developed metric called the mitigation factor. Linear models proved TI to be the best predictor of the 10th, 30th, 50th, 70th, and 90th percentiles of the distributions of peak unit discharge and rainfall-runoff ratios. In addition, TI was the best predictor of a watershed’s ability to buffer small rain events and the rate at which a stream responds once that buffering capacity is exceeded. Additional variables describing hydrograph record flashiness and water yield were best correlated to unmitigated imperviousness and forest coverage, respectively. For the range of watersheds considered, simple metrics that quantify SCM mitigation of both total watershed area and impervious area were neither the strongest primary control nor a consistent, secondary control on storm event behavior across sites. The dominance of TI as a control on hydrology over metrics of stormwater mitigation could either be attributed to the range of sites considered (14 out of 16 sites had less than 20% SCM mitigated area) or because the watershed metrics were not able to consider the spatial arrangement of impervious surfaces and SCMs. Our results have implications for policy makers designing standards that seek to minimize stream ecosystem degradation due to hydrologic disturbances from urbanization.

Post-doc Opportunity in Watershed Modeling at Kent State University

This position has been filled. Thanks for your interest.

Post-doctoral Associate in Watershed Modeling

A post-doctoral position focusing on hydrologic modeling of urban watersheds is available in the Department of Geology, Kent State University, in the lab of Anne Jefferson (http://all-geo.org/jefferson/research/). The successful candidate will have experience using RHESSys or another distributed watershed model and interest in applying their skills to questions about the effects of green infrastructure and climate change in urban areas. The post-doc will be expected to contribute to research design and undertaking, publication, and pursuit of external funding. There will also be the potential to develop additional projects building on the strengths, interests, and expertise of the successful candidate. The post-doc will have access to a wealth of data sets, field sites and instrumentation; an interdisciplinary, collaborative group of researchers and external partners focused on urban ecosystems; and a campus mentoring program for postdocs.

Kent State University (www.kent.edu), the second largest university in Ohio, is a state-supported, doctoral degree granting institution ranked as ‘high research’ by the Carnegie Foundation. The Department of Geology (www.kent.edu/geology/) has a strong graduate program (both MS and Ph.D. degrees) in both applied and basic areas of geologic research. The city of Kent combines the eclectic atmosphere of a small midwest college town with easy access to major metropolitan centers, including Cleveland, Akron, Columbus, and Pittsburgh.

Salary will be commensurate with experience and includes a competitive benefits package. Funding is initially available to support 1.5 years of work and opportunities will be sought to extend the support. If you are interested in learning more about the position, e mail Anne Jefferson (ajeffer9 at kent edu) with your CV, a description of your interests and experiences, and contact information for three people willing to serve as references. Review of applications will begin March 1st and continue until the position is filled. Kent State University is an Affirmative Action/Equal Opportunity Employer and encourages interest from candidates who would enhance the diversity of the University’s faculty.

Stormwater-Stream Connectivity: Process, Context, and Tradeoffs

In a few minutes, I’ll be giving a cyberseminar in CUAHSI’s fantastic sustainable urban streams seminar series. You can join the seminar live at 3:30 pm, or watch a recording of it later. Either way, https://www.cuahsi.org/Posts/Entry/13551 is where you want to go to watch and listen. If you want to know what you’re in for, I’ve attached my late-breaking abstract below. The whole series has been really superb, with great speakers making key points about the state-of-the-science in urban streams and watersheds. I’m honored to be part of the lineup, and I encourage you to check out all of the recordings. Enjoy!

Stormwater-Stream Connectivity: Process, Context, and Tradeoffs

Anne Jefferson

Streams in urban areas are often said to suffer from “urban stream syndrome” resulting in degraded geomorphology, biogeochemistry, and ecosystem function. Uncontrolled or poorly controlled stormwater is a root cause of many of the symptoms of urban stream syndrome, so understanding how stormwater management options affect in-stream processes is important for creating sustainable urban streams. Today’s approaches to stormwater control include green infrastructure distributed throughout the watershed and more centralized stormwater control ponds and wetlands located near the stream. How well do these approaches minimize risks to human health and infrastructure and protect aquatic ecosystems? In this talk, I’ll suggest that the answer depends on three factors: context; process; and tradeoffs. In terms of context, watersheds and stormwater management efforts are situated within a particular natural landscape (climate, soils, etc.); relative to urban development (age and style of development, type of infrastructure); and within the social context of environmental attitudes and economic constraints and incentives. Processes upslope of stormwater controls that affect water quantity and quality and processes within the controls themselves, such as mixing, infiltration and residence time, exert significant influence on how urban stream hydrology, water quality, and ecology responds to stormwater inputs. Where stormwater ponds and wetlands (SCMs) are large inputs to a stream, they can impart distinct water quality signals, and such SCMs are unlikely to restore pre-development stream water quantity and quality. Distributed green infrastructure shows promising reductions in peakflows and total stormwater volumes at the street-scale, but challenges remain in scaling up to enough projects to make a difference at the watershed scale and in ensuring that variability in construction and maintenance don’t reduce the effectiveness of the green infrastructure. Finally, there are tradeoffs in our choices around stormwater management infrastructure, in terms of the broader environmental benefits it can provide versus a more narrow focus on water quantity and quality. Using an ecosystem services framework, I show one approach to examining these tradeoffs. None of the current approaches to managing stormwater are a panacea, but with process-based, contextual studies that also examine limitations and tradeoffs, we can move the science and practice of stormwater management toward better outcomes and more sustainable urban streams.

Watershed Hydrology Trip to Susquehanna Shale Hills Critical Zone Observatory

Kent State University Department of Geology’s Watershed Hydrology class visited the Susquehanna Shale Hills Critical Zone Observatory on April 5-6, 2014. Penn State post-doc Pamela Sullivan gave them a tour of the watershed and its instrumentation, with a focus on how the measurements could contribute to understanding how hydrology drives landscape evolution on shales. The students were introduced to the challenges of hydrologic field work as they attempted to produce a continuous flow of water from a 75′ foot deep well on the watershed’s ridgeline. On Sunday, the students learned and practice water quality sampling protocols and collected water samples from streams and shallow wells in the CZO watershed and in watersheds with differing geology.Temperature, pH, specific conductance, and DO were measured in the field, and ions, cations, and stable isotopes will be measured in laboratories at Penn State and Kent State. The students will discuss these data in class over the next several weeks as they integrate their understanding of how geology and topography control hydrologic flowpaths, streamflow generation mechanisms, and water quality.

students, sign, forest in background

Kent State watershed hydrologists in front of the CZO sign. Photo by Pam Sullivan, April 2014.

Three people, one ISCO.

Pam Sullivan explains how an ISCO water sampler works.

3 students, tubing, filter, bottle.

Collecting a water sample from a well at the SSH CZO.

Kimm with a pipe wrench.

Kimm Jarden and Sebastian Dirringer are put to work cleaning a water retrieval system for one of the deeper wells in the CZO.

Students write in notebooks in a forest near a PVC well.

Recording data on the YSI from one of the shallow wells at the CZO.

The class stayed on the shores of Lake Perez, which has been drained for the last few years to enable repairs on the dam. The lake has just begun refilling, but while empty it has created some interesting research opportunities.

Students in front of a sign for Lake Perez.

Kent State students enjoyed seeing a mostly empty reservoir. It’s neat to be able to see a dam, spillway, and what the reservoir bottom looks like without any water.

Person, grass, tall wells.

Pam Sullivan describes the well field at Katie Creek. This area will soon be inundated by the refilling of Lake Perez. Some wells are being raised up, so that Penn State scientists can assess the effects of the reservoir refilling on local groundwater dynamics.

Kent State students at work collecting water samples at the Katie Creek well field.

Kent State students at work collecting water samples at the Katie Creek well field.

Krista Booth collects a water sample from Lake Perez, which integrates all of the other watersheds we sampled.

Krista Booth collects a water sample from Lake Perez, which integrates all of the other watersheds we sampled.

I’ll try to add some more beauty shots of the CZO watershed at some point, but I wanted to be able to show our class in action in the field.

Save the Date: CUAHSI Biennial Meeting, July 28-30, 2014

logoThe Consortium for the Advancement of Hydrologic Science, Inc. (CUAHSI) is a go-to group for hydrology workshops, conferences, and networking. Their once-every-two-years meeting is a great chance to hear some fantastic talks, meet other researchers and students, and share your work. This year’s meeting is in Sheperdstown, WV (a mere 4.5 hours from Kent) on July 28-30th, and the theme is “Water Across the Critical Zone: From Local to Global Hydrology.” I’m hoping my schedule allows me to be there, and I’m encouraging my students to go too. Hope to see you there!

CUAHSI Cyberseminar on Watershed Sensitivity to Climate and Land Use Change

From an email to CUAHSI members today:

A quick reminder that we invite you to join us for a special CUAHSI Cyberseminar this Thursday at a special time hosted by Roy Haggerty,  Tom Meixner, and Patrick Belmont, members of the Water, Sustainability and Climate  (WSC) community.

Thursday, January 23rd, 2 -3 PM ET

Dr. Thomas Johnson

EPA Office of Research and Development

Watershed Modeling to Assess  the Sensitivity of Streamflow, Nutrient, and Sediment Loads to  Potential Climate Change and Urban Development in 20 U.S. Watersheds

Join the seminar at: http://cuahsi.adobeconnect.com/cyberseminar/

Dr. Johnson will discuss the release of the final report released by EPA this fall. From the release:

“There is growing concern about the potential effects of climate change on water resources. To develop this report, watershed modeling was conducted in 20 large U.S. watersheds to characterize the sensitivity of streamflow, nutrient (nitrogen and phosphorus), and sediment loading to a range of plausible mid-21st century climate change and urban development scenarios. The report also provides an improved understanding of methodological challenges associated with integrating existing tools (e.g., climate models, downscaling approaches, and watershed models) and data sets to address these scientific questions. To view the study and related links, visit: http://cfpub.epa.gov/ncea/global/recordisplay.cfm?deid=256912.”

Please join us on January 23rd. Dr. Johnson will present on the results of the report, and there will be a Q&A following the presentation.

Our regular Cyberseminar series will have a spring theme of “Snow Hydrology,” and is being hosted/organized by Dr. Jessica Lundquist (Washington). The spring series begins February 7th. See http://www.cuahsi.org/Cyberseminars.aspx for more info.

Virtual workshop on laser isotope technology applications in hydrology

CUAHSI is the consortium of universities for the advancement of hydrologic science, inc. and Kent State University became a full member of the consortium in December 2013. That’s good timing, because for the last year I’ve been sitting on the organizing committee for a virtual workshop sponsored by CUAHSI and USGS, and I’m super excited to announce that it’s finally happening and starting soon.

This workshop focuses on field hydrology and biogeochemistry applications of laser-based isotope technology. This may sound like an esoteric topic, but this technology is rapidly expanding the affordability and availability of stable isotope analyses. When I was in graduate school, the only way to get water isotope data was off an expensive and hard to use isotope ratio mass spectrometer. I traveled 10 hours to access one and I swore I’d never have one in my lab. Now, I walk upstairs to use the slightly less expensive and somewhat easier to use laser spec purring along in my lab. Viva technology!

Over the course of 5 weeks, we’ll have presentations from the manufacturers of the two main laser specs (Picarro and Los Gatos Research), commentary on the technology from experts at the USGS and IAEA, examples of applications from experienced users, and a poster session where we can share our data and experiences. The workshop will occur entirely on the web (thanks, sequester) and you can participate in real time or watch recordings of the talks.

The flyer below gives a lot of the information, but you can out even more at the CUAHSI webpage for the workshop.

LaserSpec_Instrumentation_Flyer_01.07.2014

I’m looking forward to learning a ton of information during the workshop, sharing some hot-off-the-instrument data that my undergraduate student and I have been collecting, and hopefully sharing the neat ways we’re integrating the technology into our undergraduate geosciences curriculum at KSU. I hope to see you (virtually) there!

GSA 2013: Revisiting watershed drainage density: New considerations for hydrologic prediction

While I’ll be missing the festivities at the 125th anniversary edition of the the Geological Society of America, my able collaborator Sarah Lewis will be presenting our work in a session on “Quaternary Geology and Geomorphology: Past, Present, and Future.” Here’s what she’ll be showing off:

Revisiting watershed drainage density: New considerations for hydrologic prediction

S.L. Lewis, M. Safeeq, A.J. Jefferson, G.E. Grant

Watershed morphometry has long been identified as a major control on the shape and character of the hydrograph. Easily extractable landscape-level metrics have been explored for hydrologic prediction in ungaged watersheds, with varying success. In particular, mean drainage density (stream length/watershed area), which has a strong theoretical relationship to flow, has been both heralded and cast aside as an explanatory variable for hydrograph characteristics. However, previous approaches did not account for the spatial heterogeneity in drainage density within a single watershed. For example, many watersheds in the Oregon Cascades are comprised of both young lava flows with limited drainage networks, subtle peaks and sustained baseflows, and older highly dissected volcanics with steep slopes and flashy hydrographs. A mean drainage density fails to represent this dichotomy.

Here we revisit the long-standing conceptualization of drainage density as a good predictor of flow behavior at the landscape level. We depict drainage density (Dd) heterogeneity as a probability distribution function (pdf) of individual drainage densities within a watershed. Rather than limiting Dd to a single number (mean), we use standard quantitative descriptors of the pdf to explore landscape-level controls on flow regime. Two watersheds with similar mean values may have dramatically different pdfs and therefore exhibit variations in flow dynamics. We assert that some of the inconsistent results applying Dd as a predictive variable may be due to the accuracy with which a mean value can capture the behavior of a drainage network. In watersheds where drainage density is homogeneous, mean Dd may provide a good approximation of drainage behavior, but in watersheds where drainage density is heterogeneous, quantitative descriptors of the pdf can provide additional insight into flow dynamics.