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Water Management Association of Ohio conference abstract: A Neighborhood-Scale Green Infrastructure Retrofit

I was asked to submit an abstract for the Water Management Association of Ohio conference in November. I’m going to try to sum up 4 years worth of work on the green infrastructure retrofit we’ve been studying in Parma, and I’m looking forward to learning about from the other presenters at this very applied conference.

A Neighborhood-Scale Green Infrastructure Retrofit: Experimental Results, Model Simulations, and Resident Perspectives

Anne J. Jefferson, Pedro M. Avellaneda, Kimberly M. Jarden, V. Kelly Turner, Jennifer M. Grieser

There is growing interest in distributed green infrastructure approaches to stormwater management that can be retrofit into existing development, but there are relatively few studies that demonstrate effectiveness of these approaches at the neighborhood scale. In suburban northeastern Ohio, homeowners on a residential street with 55% impervious surface were given the opportunity to receive free rain barrels, rain gardens, and bioretention cells. Of 163 parcels, only 22 owners (13.5%) chose to participate, despite intense outreach efforts. After pre-treatment monitoring, 37 rain barrels, 7 rain gardens, and 16 street-side bioretention cells were installed in 2013-2014. The monitoring results indicate that the green infrastructure succeeded in reducing peak flows by up to 33% and total runoff volume by up to 40% per storm. The lag time between precipitation and stormflow also increased. A calibrated and validated SWMM model was built to explore the long-term effectiveness of the green infrastructure under 20 years of historical precipitation data. Model results confirm that green infrastructure reduced surface runoff and increased infiltration and evaporation. The model shows that the green infrastructure is capable of reducing flows by >40% at the 1, 2, and 5 year return period, and that, in this project, more benefit is derived from the street-side bioretention cells than from the rain barrels and gardens that treat rooftop runoff. Surveys indicate that many residents viewed stormwater as the city’s problem and had negative perceptions of green infrastructure, despite slightly pro-environment values generally. Substantial hydrological gains were achieved despite low homeowner participation. The project showcases the value of careful experimental design and monitoring to quantify the effects of a green infrastructure project. Finally, the calibrated model allows us to explore a wider range of hydrologic dynamics than can be captured by a monitoring program.

The effect of antecedent soil moisture conditions on green roof runoff water quality and quantity

Lab alumna and 2015 REU student Jillian Sarazen is presenting her work this week at the 59th Annual Conference on Great Lakes Research, affectionately known as IAGLR. Jillian graduated from Oberlin College in May. Congratulations on both fronts, Jillian!

The effect of antecedent soil moisture conditions on green roof runoff water quality and quantity.

SARAZEN, J.C.1, KINSMAN-COSTELLO, L.E.2, JEFFERSON, A.J.3, and SCHOLL, A.4,

1. Oberlin College Department of Biology, Oberlin, OH, 44074, USA;
2. Kent State University Department of Biological Sciences, Kent, OH, 44240, USA;
3. Kent State University Department of Geology, Kent, OH, 44240, USA;
4. Kent State University Department of Geography, Kent, OH, 44240, USA.

One of the many benefits of green roofs is that they reduce the amount of stormwater runoff as compared to normal roofs, however they can negatively impact water quality. This study was conducted at the three year-old green roof on Cleveland Metropark’s Watershed Stewardship Center in Parma, Ohio. The objectives were to (1) measure green roof runoff quantity and quality of phosphate (PO43-), nitrate (NO3-) and ammonium (NH4+) concentrations during rain events and (2) relate antecedent soil moisture conditions to water quality and quantity. We sampled sequential water samples (Teledyne, ISCO) during four summer 2015 rain events that varied in size and intensity. We measured soil moisture at high temporal resolution using four logging sensors and two to three times per week at 33 sampling locations using a handheld probe. Soil moisture increased immediately upon commencement of rainfall. Spatial data show a response in the soil to rain events with high variability, but no clear patterns. Phosphate export increased linearly with total outflow, while ammonium and nitrate export did not show clear relationships with outflow quantity. Results of our study show that there is a trade off between ecohydrologic function and water quality, as indicated by leaching of excess nutrients in the green roof outflow.

Keywords: Water quality, Green Roof, Urban watersheds, Green Infrastructure, Lake Erie.

Soil moisture dynamics and their effect on bioretention performance in Northeast Ohio

Most members of the Watershed Hydrology lab chose to go to GSA this year, and we had a blast sharing our science and enjoying Vancouver and surrounding areas. But now we are sadly missing out on the American Geophysical Union (AGU) meeting going on this week. Fortunately, a small piece of our work will be represented by outstanding summer REU student Sidney Bush. She’s giving a poster on Thursday afternoon in the Moscone West poster hall at H43F-1017. Here’s her abstract:

Soil moisture dynamics and their effect on bioretention performance in Northeast Ohio

Sidney A. Bush1, Anne Jefferson2, Kimberly Jarden2, Lauren E Kinsman-Costello2 and Jennifer Grieser3, (1)University of Virginia Main Campus, Charlottesville, VA, United States, (2)Kent State University Kent Campus, Kent, OH, United States, (3)Cleveland Metroparks, Parma, OH, United States

Urban impervious surfaces lead to increases in stormwater runoff. Green infrastructure, like bioretention cells, is being used to mitigate negative impacts of runoff by disconnecting impervious surfaces from storm water systems and redirecting flow to decentralized treatment areas. While bioretention soil characteristics are carefully designed, little research is available on soil moisture dynamics within the cells and how these might relate to inter-storm variability in performance. Bioretentions have been installed along a residential street in Parma, Ohio to determine the impact of green infrastructure on the West Creek watershed, a 36 km2 subwatershed of the Cuyahoga River. Bioretentions were installed in two phases (Phase I in 2013 and Phase II in 2014); design and vegetation density vary slightly between the two phases. Our research focuses on characterizing soil moisture dynamics of multiple bioretentions and assessing their impact on stormwater runoff at the street scale. Soil moisture measurements were collected in transects for eight bioretentions over the course of one summer. Vegetation indices of canopy height, percent vegetative cover, species richness and NDVI were also measured. A flow meter in the storm drain at the end of the street measured storm sewer discharge. Precipitation was recorded from a meteorological station 2 km from the research site. Soil moisture increased in response to precipitation and decreased to relatively stable conditions within 3 days following a rain event. Phase II bioretentions exhibited greater soil moisture and less vegetation than Phase I bioretentions, though the relationship between soil moisture and vegetative cover is inconclusive for bioretentions constructed in the same phase. Data from five storms suggest that pre-event soil moisture does not control the runoff-to-rainfall ratio, which we use as a measure of bioretention performance. However, discharge data indicate that hydrograph characteristics, such as lag time and peak flow, are altered relative to a control street. This analysis suggests that street-scale implementation of bioretention can reduce the impact of impervious surface on stormflows, but more information is needed to fully understand how soil moisture of the bioretentions affects inter-storm variability in performance.

Sidney’s poster is part of a session on “Water, Energy, and Society in Urban Systems” that Anne nominally helped convened. Check out all of the stimulating morning talks and awesome afternoon posters on Thursday. The rest of us are sorry to be missing it, but if *you* are in San Francisco at AGU this week, don’t miss out on all the great science in the session.

Development of hyporheic exchange and nutrient uptake following stream restoration

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.

Stormwater control measures modify event-based stream temperature dynamics in urbanized headwaters

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…

Stormwater control measures modify event-based stream temperature dynamics in urbanized headwaters

Grace Garner1, Anne Jefferson2*, Sara McMillan3, Colin Bell4 and David M. Hannah1
1School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.
2Department of Geology, Kent State University, Kent, OH, 44240, USA
3Department of Civil and Environmental Engineering, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA
4Department of Infrastructure and Environmental System, University of North Carolina at Charlotte, Charlotte, NC, 28223, USA

Urbanization is a widespread and growing cause of hydrological changes and ecological impairment in headwater streams. Stream temperature is an important control on physical, chemical and ecological processes, and is an often neglected water quality variable, such that the effects of urban land use and stormwater management on stream temperature are poorly constrained. Our work aims to identify the influence of stormwater control measures (SCMs) of differing design and location within the watershed on the event-based temperature response of urban streams to precipitation in the North Carolina Piedmont, in order to improve prediction and management of urban impacts. Stream temperature was measured within SCMs, and upstream and downstream of them in two streams between June and September 2012 and 2013. Approximately 60 precipitation events occurred during that period. To unambiguously identify temperature increases resulting from precipitation, surges were identified as a rise in water temperature of ?0.2°C between the hours of 15:30 and 5:30, when the diurnal temperature cycle is either decreasing or static on days without precipitation. Surges up to 5°C were identified in response to precipitation events, with surges occurring both upstream and downstream of the SCM under some conditions. Surges were also recorded within the SCMs, confirming that temperature surges are the result of heated urban runoff. Classification tree modeling was used to evaluate the influence of hydrometeorological drivers on the generation and magnitude of temperature surges. In both streams, event precipitation, antecedent precipitation, and air temperature range were identified as the drivers of whether or not a surge was observed and how large the surge was, though the order and thresholds of these variables differed between the two sites. In a stream with an off-line, pond SCM, the presence of the pond in the lower 10% of the watershed did not affect the magnitude of temperature surges within the stream, but the pond itself had a wider range of surge magnitudes than did the stream. In a watershed with a large in-line pond, and a downstream contributing wetland SCM receiving flow from 40% of the watershed, the wetland increased both the frequency and magnitude of temperature surges observed in the stream. Our results suggest dynamic hydrometeorological conditions, SCM design, and position within a watershed all influence whether stormwater management reduces or enhances temperature surges observed within urban headwater streams, and that these factors should be considered in the recommendations for urban stormwater management systems.

Assessing impacts of green infrastructure at the watershed scale for suburban streets in Parma, Ohio

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…

Assessing impacts of green infrastructure at the watershed scale for suburban streets in Parma, Ohio

Kimberly Jarden, Anne Jefferson, Jennifer Grieser, and Derek Schaefer

High levels of impervious surfaces in urban environments can lead to greater levels of runoff from storm events and overwhelm storm sewer systems. Disconnecting impervious surfaces from storm water systems and redirecting the flow to decentralized green infrastructure treatments can help lessen the detrimental effects on watersheds. The West Creek Watershed is a 36 km2 subwatershed of the Cuyahoga River that contains ~35% impervious surface. We seek to evaluate the hydrologic impacts and pollution reduction of street scale investments using green infrastructure best management practices (BMPs), such as rain gardens, bioretention, and rain barrels. Before-after-control-impact design will pair two streets with 0.001-0.002 ha. lots and two streets with 0.005-0.0075 ha. lots. Flow meters have been installed to measure total discharge, velocity, and stage pre– and post-construction. Runoff data has been preliminarily analyzed to determine if peak discharge for large (> 10 mm) and small (<10 mm) storm events has been reduced after installation of BMPs on the street with 0.001-0.002 ha. lots. Initial results show that the peak flows have not been reduced for most storm events on the street with the green infrastructure. However, several larger events show that peak flows have been reduced on the treatment street and need to be further investigated to ensure no outside hydrological impacts are having an effect on the flow. Initial analysis of total flow volume for each event, pre- and post-construction, show that total volume has increased on the street with green infrastructure treatments. Possible explanation for the increase on flow volume could be attributed to under drains from bioretention creating a more connected flow path to the storm drain or an upstream leak in the control street storm drain. Each scenario will be investigated further to confirm results. Further research will include analysis of the total effect of street-scale BMPs on storm hydrograph characteristics including, hydrograph regression behavior and lag time. Analysis on the accumulation of metals in the bioswales and the reduction of metals in street runoff will also be conducted to determine if the BMP treatments are capturing pollutants associated with storm water. After studying the effect of each individual treatment, we will define the level of disconnected impervious surfaces needed in order to achieve a natural hydrologic regime in this watershed.

After the dam comes out: groundwater-stream interactions and water quality impacts of former reservoir sites

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.

Sensitivity of precipitation isotope meteoric water lines and seasonal signals to sampling frequency and location

Allison ReynoldsThis work is being conducted by undergraduate lab member, Allison Reynolds. Allison presented her work as part of the CUAHSI/USGS Virtual Workshop on applications of laser specs to hydrology and biogeochemistry. From that workshop, she will have an extended abstract published in a USGS open file report, and her poster will continue to be viewable on-line. She will also be presenting results at the inaugural Kent State Undergraduate Research Symposium in April. And of course, she’s going to keep working on new data and analyses and aiming for publication. Go Aly!

Sensitivity of precipitation isotope meteoric water lines and seasonal signals to sampling frequency and location
Allison R. Reynolds (areyno13@kent.edu) and Anne J. Jefferson (advisor)
Department of Geology, Kent State University, Kent, OH 44242

Our purpose is to compare seasonal signal and local meteoric water line (LMWL) generated by analyzing hydrogen and oxygen isotopes in precipitation for one year of event-based sampling to those from multi-year monthly sampling at the closest Global Network of Isotopes in Precipitation (GNIP) stations. The question we seek to answer is whether data from different sampling strategies, periods, and locations within the eastern Great Lakes region on a regional-scale LMWL and seasonal signal. We collected precipitation samples after each event in Kent, OH. Samples were analyzed with a Picarro L-2130i. The closest GNIP sites are Coshocton, Ohio and Simcoe, Ontario. LMWLs and seasonal signals derived from monthly samples were broadly similar along a 300 km north-south transect in the US eastern Great Lakes Region. Monthly volume-weighted averages of event precipitation under-represent event scale isotopic variability, based on samples from Kent, Ohio.

Abstract: Using Computer Modeling To Asses Hydraulic Parameter Transferability From An Undeveloped To An Urban Watershed With Stormwater Infrastructure

Rounding out the abstracts from our group for the 2012 Geological Society of America meeting, Colin Bell will be presenting preliminary model results.

USING COMPUTER MODELING TO ASSES HYDRAULIC PARAMETER TRANSFERABILITY FROM AN UNDEVELOPED TO AN URBAN WATERSHED WITH STORMWATER INFRASTRUCTURE

BELL, Colin D., Dept. Infrastructure and Environmental Systems, UNC Charlotte, Charlotte, NC 28262, cdbell01@yahoo.com, MCMILLAN, Sara, Department of Engineering Technology, University of North Carolina at Charlotte, Charlotte, NC 28223, JEFFERSON, Anne J., Department of Geology, Kent State University, 221 McGilvrey Hall, Kent, OH 44240, TAGUE, Christina, Bren School of Environmental Science and Management, University of California-Santa Barbara, Santa Barbara, CA 93106, and CLINTON, Sandra, Department of Geography and Earth Sciences, University of North Carolina at Charlotte, Charlotte, NC 28223

Urban infrastructure expansion causes the alteration of hydrologic and nutrient regimes during storms, elevating peak discharges and nitrogen (N) concentrations in receiving streams. The inclusion of stormwater Best Management Practices (BMPs) in urban watersheds has been found to help ameliorate these problems by attenuating hydrographs and reducing N concentrations through denitrification and uptake. The Regional Hydro-Ecological Simulation System (RHESSys) is a distributed, process-based model that simulates hydrologic activity as well as natural and anthropogenic N processing and export. RHESSys is being used to develop hydro-ecological models to assess the impact of different BMP implementation strategies on instream N in a developing residential watershed in Charlotte, NC where water quality and land use data accompany 10 years of hydrologic data. Hydraulic parameter sets have been calibrated to simulate subsurface water propagation in a nearby, undeveloped watershed with no existing stormwater infrastructure. The suitability of these parameter sets has been assed using the GLUE uncertainty prediction procedure, a calibration and uncertainty estimation method that addresses the equifinality of parameter sets given errors in model structure and observed data. The viability for transferring the model parameters to the urban watershed has been analyzed by comparing an observed discharge record with one predicted using calibrated parameters. Future RHESSys simulations will test multiple, spatially-explicit scenarios to identify the BMP treatment scenarios that minimize aquatic ecosystem degradation.

Abstract: Evaluating restoration effects on transient storage and hyporheic exchange in urban and forested streams

A third abstract from our group for the 2012 Geological Society of America meeting:

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, mosypian@uncc.edu, 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.