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ELOHA News Winter 2014
Practitioner updates on the Ecological Limits of Hydrologic Alteration, a scientific framework for determining and applying environmental flows at large regional scales.

March 3, 2014

1.       North Carolina panel recommends ELOHA-based approach

North Carolina’s 2009 Water Policy Act requires the Department of Environment and Natural Resources to determine the flows needed to maintain ecological integrity in surface waters, and authorized the creation of a Science Advisory Board to assist in assessing ecological flows.  In November, the Board
recommended combining a percent-of-flow strategy (80-90% allowable flow alteration) with an ELOHA-based biological-response strategy.  The latter relates statewide fish and invertebrate data to modeled flow alteration using 80th percentile quantile regressions, as documented in Appendix D of the report.
Contact: Jennifer Phelan

2.       California panel recommends hybrid IFIM-ELOHA approach

In accordance with the Delta Reform Act of 2009 and the Delta Plan, the State Water Resources Control Board is developing flow objectives for high-priority tributaries to the Sacramento-San Joaquin Delta. Upon the Board’s request, the Delta Stewardship Council’s Delta Science Program organized an independent panel to review existing flow criteria methods and make recommendations to the Board.  The  final report recommends adopting an approach that “draws from the strengths of both the IFIM and ELOHA methodologies, acknowledging the climatology, hydrology, and geomorphology of California.”

3.       Hydrologic foundation completed for southeastern USA

RTI International completed a 1-year pilot project to build a unified hydrologic model of the South Atlantic Landscape Conservation Cooperative (SALCC) region.  RTI used WaterFALLTM to model daily streamflow for every NHDPlus stream reach within 12 major (HUC-6) watersheds under baseline conditions and within 6 of those watersheds under current and future conditions.  The SALCC uses the model to understand hydrologic impacts of land use, water use, and climate changes, as well as flow-ecology relationships for regional conservation planning.  For more information contact: Michele Eddy.

4.       New York water withdrawal regulations:  e-flow ready!

As reported in the last ELOHA News, new regulations pursuant to the 2011 Water Resources Protection Act authorized New York State to develop water withdrawal permitting, subject to quantitative streamflow standards that maintain aquatic life.
In September, The Nature Conservancy completed a 2-year project to put those pieces together.  Engaging technical experts from agencies, universities, and stakeholder groups, the Conservancy quantified e-flows for all types of Great Lakes tributaries in New York and Pennsylvania, recommended water withdrawal permitting policies that would protect those flows, and evaluated their impacts on water users.  The project applied and expanded upon the ELOHA approach that informed the recently adopted low-flow protection policy in the Susquehanna River basin.

5.       E-flows defined for Upper Ohio River Basin, Pennsylvania

The Nature Conservancy provided ELOHA-based e-flow recommendations for the entire upper Ohio River basin to the Pennsylvania Department of Environmental Protection (DEP) in March 2013.  The culmination of streamflow analyses, four expert workshops and the synthesis of more than 150 publications, these recommendations support statewide instream flow policy development and may also guide site‐specific reservoir operations. 
Contact:  Michele DePhilip

6.       Conservation Planning Atlas:  ELOHA on steroids!

The Southeast Aquatic Resources Partnership’s new Conservation Planning Atlas displays river classification, flow alteration, flow-sensitive species distributions, and myriads of other information for the southeastern USA.  A recorded webinar demonstrates how to use the Atlas to determine potential ecological impacts of a surface-water withdrawal, assess the status of instream flows in a state or region for water management planning, identify priority areas where flow-sensitive species are threatened by flow alteration, and test flow-ecology hypotheses.

7.       US EPA releases Watershed Management Optimization Support Tool

U.S. Environmental Protection Agency (EPA) released Watershed Management
Optimization Support Tool (WMOST), a new public-domain software application to support regional water resource planning and management.  Users can screen a wide range of practices for cost-effectiveness in achieving watershed or water utility management goals such as meeting projected water demand and ecological flow targets.

8.       New IHA and ELOHA Toolbox websites

The ELOHA Toolbox and Indicators of Hydrologic Alteration (IHA) software websites have moved.  Shortcuts for their new homes are and

9.       New projects

Trialing the national e-flows standard in Chiapas, Mexico

The Nature Conservancy is using ELOHA to determine e-flow needs for the Chiapas coastal watersheds in Mexico.  The 25 watersheds run directly from the Chiapas Sierra Madre to the sea and include three important biosphere reserves – El Triunfo, La Sepultura, and La Encrucijada – that protect a connected landscape of cloud forests, tropical rainforest, and extensive and biologically rich coastal wetlands.  Project goals are to:  1) serve as a model for implementing Mexico’s new national standard on environmental flows and 2) provide information for reducing risk, increasing resilience, and improving “green infrastructure” opportunities.
Contact: Jeanmarie Haney

Determining effects of flow alteration on Atlantic Highlands stream ecology, USA

U.S. Geological Survey, through its National Water-Quality Assessment (NAWQA)
Program, is adapting ELOHA to determine how flow alteration relates to aquatic
ecosystem health, as indicated by changes in thermal regime, physical habitat, water chemistry, and aquatic biota.  For more information, see attached fact sheet.

Accelerating endangered species recovery in Montana, USA

The U.S. Forest Service and local partners recently held their first expert workshop
to develop hydrologic and biologically based instream flow metrics for bull trout
and westslope cutthroat trout conservation and recovery in northwestern Montana,
USA. The resulting regional flow standards will inform site-specific water-right
applications for instream flows. 
Contact: Bob Deibel

Applying ELOHA to California’s wadeable streams

Southern California Coastal Water Research Project, Colorado State University, U.S. Geological Survey, and California Department of Fish and Wildlife are collaborating on a 2-year project to develop an approach for establishing instream environmental flow requirements necessary to meet ecological benchmarks as defined by measures of benthic macroinvertebrate community composition and structure.  These requirements can then be used to help establish criteria for use in hydromodification management, nutrient numeric endpoints, and freshwater Bioobjectives. 
Contact: Eric Stein

10.   New publications

Arthington, A.H. 2012. Ecological Limits of Hydrologic Alteration -  ELOHA, Chapter 13 In: “Environmental Flows: Saving Rivers in the Third Millennium”. University of California Press, Berkeley, CA. 406pp.

Arthington, A.H., Rolls, R., Sternberg, D., Mackay, S.J., James, C.S. 2014.
Fish assemblages in sub-tropical rivers: low flow hydrology dominates
hydro-ecological relationships. Hydrological Sciences Journal 01/2014
DOI:10.1080/02626667.2013.844345. [abstract]

Bryan BA, Higgins, A.,Overton, I. C.,Holland, K.,Lester, R.E.,King, D.,Nolan, M.,
Hatton MacDonald, D.,Connor, J.D., Bjornsson, T., Kirby, M.. 2013. Ecohydrological and socioeconomic integration for the operational management of environmental flows. Ecological Applications 23: 999–1016
DOI:10.1890/12-2104.1. [abstract]

Campbell CJ, Johns CV, Nielsen DL. 2014. The value of plant functional groups in
demonstrating and communicating vegetation responses to environmental flows.
Freshwater Biology  DOI:10.1111/fwb.12309. [abstract]
Study area: lower Murray-Darling wetlands.

Davies PM, Naiman RJ, Warfe DM, Pettit NE, Arthington AH, Bunn SE. 2014.
Flow–ecology relationships: closing the loop on effective environmental flows.
Marine and Freshwater Research 65: 133-141 DOI: 10.1071/MF13110. [abstract]
“E-flows need to be explicit about flow-ecology relationships to adequately determine the amount and timing of water required.”

Fitzhugh TW. 2013. EFCAM: a method for assessing alteration of environmental flow components. River Research and Applications DOI:10.1002/rra.2681.[abstract]
“…a useful addition to the Indicators of Hydrologic Alteration [IHA] software.”

Knight, R.R., Murphy, J.C., Wolfe, W.J., Saylor CF, Wales AK. 2013 (early view).
Ecological limit functions relating fish community response to hydrologic departures of the ecological flow regime in the Tennessee River basin, United States. Ecohydrology DOI: 10.1002/eco.1460. [full text]  
This USGS study quantifies change in fish diversity in response to streamflow alteration in the Tennessee River basin, using fish community data collected by the Tennessee Valley Authority, and predictions of streamflow characteristics at more than 600 locations.

Linhart SM, Nania JF, Christiansen DE, Hutchinson KJ, Sanders CL, Jr., Archfield SA. 2013. Comparison between two statistically based methods, and two physically based models developed to compute daily mean streamflow at ungaged locations in the Cedar River Basin, Iowa. U.S. Geological Survey Science Investigations Report 2013-5111. [full text]

Mackay SJ, Arthington AH, James CS. 2014. Classification and comparison of natural and altered flow regimes to support an Australian trial of the Ecological Limits of Hydrologic Alteration framework. Ecohydrology DOI: 10.1002/eco.1473. [abstract]

McManamay, R. A., D. J. Orth, J. Kauffman, and M. M. Davis.  2013.  A database and meta-analysis of ecological responses to stream flow in the South Atlantic
region. Southeastern Naturalist 12 (Monograph 5):1-36. [full text] 

McManamay, R. A., D. J. Orth, and C. A. Dolloff.  2013.  Application of the ELOHA
(Ecological Limits of Hydrologic Alteration) framework to the Cheoah River, a
regulated system in the Little Tennessee River basin Environmental Management,
DOI:10.1007/s00267-013-0055-3. [abstract]
“Although ELOHA provided a robust template to construct hydrologic information and predict hydrology for ungaged locations, our results do not suggest that univariate relationships between flow and ecology (step 4, ELOHA process) can produce results sufficient to guide flow restoration in regulated rivers. After constructing multivariate models, we successfully developed predictive relationships between flow alterations and fish/riparian responses.”

Olden JD, et al. 2014. Are large-scale flow experiments informing the science and
management of freshwater ecosystems? Frontiers in Ecology and the Environment. DOI: 10.1890/130076. [abstract]
Pahl-Wostl, Claudia; Angela Arthington; Janos Bogardi; Stuart Bunn; Holger Hoff;
Louis Lebel; Elena Nikitina; Margaret Palmer; LeRoy Poff; Keith Richards; Maja
Schlüter; Roland Schulze; Andre St-Hilaire; Rebecca Elizabeth Tharme; Klement
Tockner; Daniel Tsegai. 2013. Environmental flows and water governance: managing sustainable water uses. Current Opinion in Environmental Sustainability 5(3-4): 341-351 DOI:10.1016/j.cosust.2013.06.009. [abstract]

Rolls, R.J., and Arthington, A.H. 2014. How do low magnitudes of hydrologic
alteration impact riverine fish populations and assemblage characteristics?
Ecological Indicators 39: 179-188 DOI:10.1016/j.ecolind.2013.12.017. [abstract]
“Our study provides positive evidence that dams and regulated flow regimes can be managed with sensitivity such that there are few significant changes in populations of most fish species, and little change in fish assemblage characteristics.”

Shiau, J-T, Wu, F-C. 2013. Optimizing environmental flows for multiple reaches
affected by a multipurpose reservoir system in Taiwan: restoring natural flow
regimes at multiple temporal scales: Water Resources Research 49: 565-584.
DOI: 10.1029/2012WR012638. [abstract]

U.S. Geological Survey 2013.  Summary of monitoring and assessments related to
environmental flows in USGS Water Science Centers across the U.S. 26 pages. [full text] 
Includes numerous publication references, organized by State.

Webb JA, Miller KA, King EL, deLittle SC, Stewardson MJ, Zimmerman JKH, Poff NL. 2013. Squeezing the most out of existing literature: a systematic re-analysis of
published evidence on ecological responses to altered flows. Freshwater Biology
58(12): 2439-2451 DOI:10.1111/fwb.12234. [abstract]

Wilcox AC, Shafroth PB. 2013. Coupled hydrogeomorphic and woody-seedling responses to controlled flood releases in a dryland river. Water Resources Research 49: 1-18 DOI:10.1002/wrcr.20256. [abstract]

Coming soon:  Special issue of Hydrologic Sciences Journal on the changing role of ecohydrological science in guiding environmental flows, edited by Mike Acreman.

ELOHA Toolbox website

Share your resources with the entire ELOHA community by posting them on Case studies, references, links, and text additions all are welcome.  We especially encourage postings on environmental flow policy advances from outside the United States.  Send your contributions to Eloise Kendy. The site is organized according to the main steps of ELOHA, with cited references linked to a comprehensive bibliography.  Case studies from around the world are being tracked, with your help.   Thank you to all contributors, past and future.

Feel free to forward this newsletter.



Eloise Kendy, Ph.D.
Senior Freshwater Scientist

The Nature Conservancy
North America Region
415 Monroe Avenue
Helena, Montana 59601
Tel: +1 406 495 9910