Low Flow Trends in Texas Stream Segments Serving Unique Hydrologic Functions
Cover photo: Santa Elena Canyon, Big Bend National Park, Texas.  ©2022 Rob Doyle, Pluto911 Photography


Edwards Plateau
stream drying
low flow
drought index

How to Cite

Venkataraman, Kartik, Narayanan Kannan, and Victoria Chraibi. 2023. “Low Flow Trends in Texas Stream Segments Serving Unique Hydrologic Functions”. Texas Water Journal 14 (1). College Station, Texas:3-33. https://doi.org/10.21423/twj.v14i1.7143.


In recognition of the unique hydrologic functions they serve, certain stream segments in Texas have been designated as ecologically significant. In this study, we evaluated low flow trends in seven hydrologically unique stream segments spanning three climatic divisions in Texas from 1970 to 2019. Despite increasing mean annual temperatures, there are no trends in low flows or other hydrologic variables in the East Fork of the San Jacinto River in the Upper Coast climatic division, likely due to local moisture surplus effects from the Gulf of Mexico. In the Edwards Plateau climatic division, annual low flows and annual baseflows are decreasing in the South Fork of the Guadalupe River, the Sabinal River and the Frio River. While increasing mean annual temperatures appear to have a role in the drying of all three of these stream segments, increasing annual potential evapotranspiration may be an additional driver in the Sabinal and Frio Rivers. Analysis of the Standardized Streamflow Index indicates that all seven stream segments experienced their worst streamflow droughts in the 2010s. As such, the watersheds draining to the gages on these stream segments have minimal anthropogenic impacts, suggesting the influence of climate on the observed stream drying.



Acuna V, Tockner K. 2005. Drought and postdrought recovery cycles in an intermittent Mediterrean stream: structural and functional aspects. Freshwater Science. 24(4). Available from: https://doi.org/10.1899/04-078.1.

Alashan S. 2020. Combination of modified Mann-Kendall method and Sen innovative trend analysis. Engineering Reports. Available from: https://doi.org/10.1002/eng2.12131.

Bogan MT, Hwan JL, Carlson SM. 2015. High aquatic biodiversity in an intermittent coastal headwater stream at Golden Gate National Recreation area, California. Northwest Science. 89(2):188-197. Available from: https://doi.org/10.3955/046.089.0211.

Bogan MT, Chester ET, Datry, T, Murphy AL, Robson BJ, Ruhi Al, Stubbington R, Whitney JE. 2017. Resistance, resilience, and community recovery in intermittent rivers and ephemeral streams. In: Datry, T, Bonada, N, Boulton A, editors. Intermittent Rivers and Ephemeral Streams Ecology and Management. Academic Press. London: Elsevier. p. 349-376. Available from: https://doi.org/10.1016/B978-0-12-803835-2.00013-9.

Bradford MJ, Heinonen JS. 2008. Low flows, instream flow needs and fish ecology in small streams. Canadian Water Resources Journal. 33(20):165-180. Available from: https://doi.org/10.4296/cwrj3302165.

Brauer D, Baumhardt L, Gitz D, Gowda P, Mahan J. 2015. Characterization of trends in reservoir storage, streamflow, and precipitation in the Canadian River watershed in New Mexico and Texas. Lake and Reservoir Management. 31(1):64-79. Available from: https://doi.org/10.1080/10402381.2015.1006348.

Bunting G, England J, Gething K, Sykes T, Webb J, Stubbington R. 2021. Aquatic and terrestrial invertebrate community responses to drying in chalk streams. Water Environment Journal. 35(2021):229-241. Available from: https://doi.org/10.1111/wej.12621.

Cayan, DR, Dettinger, MD, Diaz HF, Graham NE. 1998. Decadal variability of precipitation over western North America. Journal of Climate. 11(12):3148-3166. Available from: https://doi.org/10.1175/1520-0442(1998)011%3C3148:DVOPOW%3E2.0.CO;2.

Chester ET, Robson BJ. 2011. Drought refuges, spatial scale and recolonization by invertebrates in non-perennial streams. Freshwater Biology. 56(10):2094-2104. Available from: https://doi.org/10.1111/j.1365-2427.2011.02644.x.

Crawford J, Venkataraman K, Booth J. 2019. Developing climate model ensembles: A comparative case study. Journal of Hydrology. 568: 160-173. Available from: https://doi.org/10.1016/j.jhydrol.2018.10.054.

Curran CA, Eng K, Konrad CP. 2012. Analysis of low flows and selected methods for estimating low-flow characteristics at partial-record and ungagged stream sites in Western Washington. United States Geological Survey Scientific Investigations Report 2012-5078. 46p. Available from: https://pubs.usgs.gov/sir/2012/5078/pdf/sir20125078.pdf.

Del Rosario RB, Resh VH. 2000. Invertebrates in intermittent and perennial streams: is the hyporheic zone a refuge from drying? Journal of the North American Benthological Society. 19(4): 680-696. Available from: https://doi.org/10.2307/1468126.

Demaria EMC, Maurer EP, Thrasher B, Vicuna S, Meza FJ. 2013. Climate change impacts on an alpine watershed in Chile: Do new model projections change the story? Journal of Hydrology. 502(10):128-138. Available from: https://doi.org/10.1016/j.jhydrol.2013.08.027.

Dierauer J, Whitfield P. 2017. FlowScreen: daily streamflow trend and change point screening. R package version 1.2.3.

Eckhardt K. 2012. Analytical sensitivity analysis of a two parameter recursive digital baseflow separation filter. Hydrological and Earth System Sciences. 16(2):451-455. Available from: https://doi.org/10.5194/hess-16-451-2012.

[EAA] Edwards Aquifer Authority. 2021a. Shapefiles (Aquifer Zones). Available from: https://www.edwardsaquifer.org/science-maps/maps/shapefiles/.

[EAA] Edwards Aquifer Authority. 2021b. Historical Data. Available from: https://www.edwardsaquifer.org/science-maps/aquifer-data/historical-data/.

González-Ferreras AM, Barquín J. 2017. Mapping the temporary and perennial character of whole river networks. Water Resources Research. 53(8):6709-6724. Available from: https://doi.org/10.1002/2017WR020390.

Green RT, Bertetti FP. 2010. Investigating the water resources of the Western Edwards-Trinity Aquifer. Final report prepared for Sutton County Groundwater Conservation District by the Geosciences and Engineering Division of the Southwest Research Institute. Available from: https://static.squarespace.com/static/535a88f6e4b0fbad919ef959/t/53864143e4b040c8980a7073/1401307459476/WesternEdwardsTrinityFinalRev1.pdf.

Uvalde County Underground Water Conservation District. 2010. Development of a candidate drought contingency plan for Uvalde County, Texas. Green RT, Bertetti FP, editors. San Antonio (Texas): Geosciences and Engineering Division, Southwest Research Institute. Available from: www.uvaldecountyuwcd.org/files/DroughPlan05242010.pdf.

Gupta SC, Kessler AC, Brown MK, Zvomuya F. 2015. Climate and agricultural land use change impacts on streamflow in the upper Midwestern United States. Water Resources Research. 51(7):5301-5317. Available from: https://doi.org/10.1002/2015WR017323.

House Bill 3 and Senate Bill 3 80th Legislature. 2007. Austin (Texas): Texas Legislative Commission. Available from: https://lrl.texas.gov/legis/billSearch/BillDetails.cfm?legSession=80-0&billTypeDetail=HB&billnumberDetail=3&submitbutton=Search+by+bill.

Hackett CC. 2019. Storage dynamics of the upper Nueces River alluvial aquifer: Implications for recharge to the Edwards Aquifer [thesis]. [Austin (Texas)]: The University of Texas at Austin. Available from: http://dx.doi.org/10.26153/tsw/5425.

Hajihoseini H, Hajihoseini M, Najafi A, Morid S, Delavar M. 2015. Assessment of changes in hydro-meteorological variables upstream of Helmand Basin during the last century using CRU data and SWAT model. Iran Water Resources Research. 2(10):38-52.

Hamed KH, Rao AR. 1998. A modified Mann-Kendall trend test for autocorrelated data. Journal of Hydrology. 204(1-4):182-196. Available from: https://doi.org/10.1016/S0022-1694(97)00125-X.

[EAA] Edwards Aquifer Authority. 2003. Edwards Aquifer Authority hydrogeological data report for 2002. San Antonio (Texas): Edwards Aquifer Authority. Report 03-02. 134 p. Available from: https://www.edwardsaquifer.org/science_docs/edwards-aquifer-authority-hydrogeologic-report-for-2002/.

Hammond JC, Zimmer M, Shanafield M, Kaiser K, Godsey SE, Mims MC, Zipper SC, Burrows RM, Kampf SK, Dodds W, Jones CN, et al. 2020. Spatial patterns and drivers of nonperennial flow regimes in the contiguous United States. Geophysical Research Letters. 48(2)1-11. Available from: https://doi.org/10.1029/2020GL090794.

Harris IC, Jones PD. 2019. CRU TS3.26: Climatic Research Unit (CRU) Time-Series (TS) Version 3.26 of High-Resolution Gridded Data of Month-by-month Variation in Climate (Jan. 1901- Dec. 2017). Norwich (England): University of East Anglia Climatic Research Unit, Centre for Environmental Data Analysis. Available from: http://dx.doi.org/10.5285/7ad889f2cc1647efba7e6a356098e4f3.

Hill MJ, Milner VS. 2018. Ponding in intermittent streams: a refuge for lotic taxa and a habitat for newly colonising taxa? Science of the Total Environment. 628-629:1308-1316. Available from: https://doi.org/10.1016/j.scitotenv.2018.02.162.

Hisdal H, Tallaksen LM, Clausen B, Peters E, Gustard A, VanLauren H. 2004. Hydrological drought characteristics. Developments in Water Science. 48(5): 139-198. Available from: https://www.academia.edu/download/79197417/Ch05_final_Elsevier-Textbook-Hydro-Drought-Tallaksen-Van-Lanen-2004.pdf.

Holling CS. 1973. Resilience and stability of ecological systems. Annual Review of Ecology and Systematics. 4(1):1-23. Available from: https://doi.org/10.1146/annurev.es.04.110173.000245.

Hirsch RM, De Cicco LA. 2015. EGRET: User guide to Exploration and Graphics for RivEr Trends (EGRET) and dataRetrieval: R packages for hydrologic data (version 3.0.2). In: Techniques and Methods, chapter A10. Reston (Virginia): United States Geological Survey. 94 p.. Available from: https://doi.org/10.3133/tm4A10.

Jiang X, Yang ZL. 2012. Projected changes of temperature and precipitation in Texas from downscaled global climate models. Climate Research. 53(3):229-244.

Jowett IG, Biggs BJF. 2006. Flow regime requirements and the biological effectiveness of habitat‐based minimum flow assessments for six rivers. International Journal of River Basin Management. 4(3):179-189. Available from: https://doi.org/10.1080/15715124.2006.9635287.

Kromann J. 2015. Surface water recharge in karst: Edwards-Trinity Aquifers-Nueces River System. Texas Scholar Works; University of Texas Libraries: Austin, Texas. Available online: https://repositories.lib.utexas.edu/handle/2152/44401.

Larson ER, Magoulick DD, Turner C, Laycock KH. 2009. Disturbance and species displacement: different tolerances to stream drying and desiccation in a native and an invasive crayfish. Freshwater Biology. 54(9):1899-1908. Available from: https://doi.org/10.1111/j.1365-2427.2009.02243.x.

Lindgren RJ, Dutton AR, Hovorka SD, Worthington SRH, Painter S. 2004. Conceptualization and simulation of the Edwards Aquifer, San Antonio region, Texas. Reston (Virginia): United States Geological Survey. USGS Scientific Investigations Report 2004-5277. 144 p. Available from: https://doi.org/10.3133/sir20045277.

Lins HF, Slack JR. 1999. Streamflow trends in the United States. Geophysical Research Letters. 26(2):227-230. Available from: https://doi.org/10.2747/0272-3646.26.6.489.

Lins HF, Slack JR. 2005. Seasonal and regional characteristics of U.S. streamflow trends in the United States from 1940 to 1999. Physical Geography. 26(6):489-501.

Lins HF. 2012. USGS hydro-climatic data network 2009 (HCDN-2009). Reston (Virginia): United States Geological Survey. Fact Sheet 3047(4). 4 p. Available from: https://pubs.usgs.gov/fs/2012/3047/pdf/fs2012-3047.pdf.

Machiwal D, Gupta A, Jha MK, Kamble T. 2019. Analysis of trend in temperature and rainfall time series of an Indian arid region: comparative evaluation of salient techniques. Theoretical and Applied Climatology. 136(1):301-320. Available from: https://doi.org/10.1007/s00704-018-2487-4.

Mahmood R, Jia S, Zhu W. 2019. Analysis of climate variability, trends, and prediction in the most active parts of the Lake Chad basin, Africa. Scientific Reports. 9(6317)1-18. Available from: https://doi.org/10.1038/s41598-019-42811-9.

McCabe GJ., Wolock, DM. 2014. Spatial and temporal patterns in conterminous United States streamflow characteristics. Geophysical Research Letters. 41(19):6889-6897. Available from: https://doi.org/10.1002/2014GL061980.

McCabe GJ, Wolock DM. 2016. Variability in runoff efficiency in the conterminous United States. Journal of the American Water Resources Association. 52(5):1046-1055. Available from: https://doi.org/10.1111/1752-1688.12431.

McKee TB, Doesken NJ, Kleist J. 1993. The relationship of drought frequency and duration to time scales. Proceedings of the Eighth Conference on Applied Climatology. 17(22):179-183.

Murgulet D, Murgulet V, Spalt N, Douglas A, Hay RR. 2016. Impact of hydrological alterations on river-groundwater exchange and water quality in a semi-arid area: Nueces River, Texas. Science of the Total Environment. 572:595-607. Available from: https://doi.org/10.1016/j.scitotenv.2016.07.198.

Mutti PR, Dubreuil V, Bezerra BG, Arvor D, de Oliveira, CP, Santos e Silva CM. 2020. Assessment of gridded CRU TS data for long-term climatic water balance monitoring over the Sao Francisco Watershed, Brazil. Atmosphere. 11(11):1-25. Available from: https://doi.org/10.3390/atmos11111207.

[NCDC] National Climate Data Center. 2015. Climate divisions for the continental United States. Available from: ftp://ftp.ncdc.noaa.gov/pub/data/cirs/climdiv/CONUS_CLIMATE_DIVISIONS.shp.zip.

Neves J. 2013. SPI: compute SPI index. R package version 1.1.

Patterson LA, Lutz B, Doyle MW. 2012. Streamflow changes in the South Atlantic, United States during the Mid-and Late-20th Century. Journal of the American Water Resources Association. 48(6):1126-1138. Available from: https://doi.org/10.1111/j.1752-1688.2012.00674.x.

Pierce D. 2015. Ncdf4: Interface to unidata netCDF format data files. R package version 1.13.

Poshtiri MP, Pal I. 2016. Patterns of hydrological drought indicators in major US river basins. Climatic Change. 134(4):549-563.

Poshtiri MP, Towler E, Pal I. 2018. Characterizing and understanding the variability of streamflow drought indicators within the USA. Hydrological Sciences Journal. 63(12):1791-1803. Available from: https://doi.org/10.1080/02626667.2018.1534240.

RStudio Team. 2019. RStudio: Integrated Development for R. RStudio, PBC, Boston MA.

Reynolds LV, Shafroth PB, Poff NL. 2015. Modeled intermittency risk for small streams in the Upper Colorado River Basin under climate change. Journal of Hydrology. 523:768-780. Available from: https://doi.org/10.1016/j.jhydrol.2015.02.025.

Richter BD, Baumgartner JV, Powell J, Braun DP. 1996. A method for assessing hydrologic alteration within ecosystems. Conservation Biology. 10(4):1163-1174. Available from: https://doi.org/10.1046/j.1523-1739.1996.10041163.x.

Robson BJ, Chester ET, Austin CM. 2011. Why life history information matters: drought refuges and macroinvertebrate persistence in non-perennial streams subject to a drier climate. Marine and Freshwater Research. 62(7):801-810. Available from: https://doi.org/10.1071/MF10062.

Rogers K, Roland V, Hoos A, Crowley-Ornelas E, Knight R. 2020. An analysis of streamflow trends in the Southern and Southeastern US from 1950–2015. Water. 12(12):1-28.. Available from: https://doi.org/10.3390/w12123345.

Santos AN, Stevenson RD 2011. Comparison of macroinvertebrate diversity and community structure among perennial and non-perennial headwater streams. Northeastern Naturalist. 18(1):7-26. Available from: https://doi.org/10.1656/045.018.0102.

Sen PK. 1968. Estimates of the regression coefficients based on Kendall’s tau. Journal of the American Statistical Association. 63(324):1379-1389.

Shukla S, Wood A. 2008. Use of a standardized runoff index for characterizing hydrologic drought. Geophysical Research Letters. 35(2):1-7. Available from: https://doi.org/10.1029/2007GL032487.

Smakhtin VU. 2001. Low flow hydrology: a review. Journal of Hydrology. 240(3-4):147-186. Available from: https://doi.org/10.1016/S0022-1694(00)00340-1.

Small D, Islam S, Voge R. 2006. Trends in precipitation and streamflow in the eastern US: Paradox or perception? Geophysical Research Letters. 33(3):1-4. Available from: https://doi.org/10.1029/2005GL024995.

Stahl K, Hisdal H, Tallaksen LM, van Lanen HA, Hannaford J, Sauquet E. 2008. Trends in low flows and streamflow droughts across Europe. Paris (France): UNESCO, 39 p. Available from: https://www.researchgate.net/publication/258498363_Trends_in_Low_Flows_and_Streamflow_Drought_Across_Europe.

Steinschneider S, Brown C. 2012. Dynamic reservoir management with real-option risk hedging as a robust adaptation to nonstationary climate. Water Resources Research. 48(5):1-16. Available from: https://doi.org/10.1029/2011WR011540.

Storey RG, Parkyn S, Neal MW, Wilding T, Croker G. 2011. Biodiversity values of small headwater streams in contrasting land uses in the Auckland region, New Zealand. J. Mar. Freshwater Research. 45(2):231-248. Available from: https://doi.org/10.1080/00288330.2011.555410.

Stubbington R, England J, Wood PJ, Sefton CEM. 2017. Temporary streams in temperate zone: recognizing, monitoring and restoring transitional aquatic-terrestrial ecosystems. WIREs Water. 4: c1223. Available from: https://doi.org/10.1002/wat2.1223.

[TAC] Texas Administrative Code § 357.43. 2020. Available from: https://texreg.sos.state.tx.us/public/readtac$ext.TacPage?sl=R&app=9&p_dir=&p_rloc=&p_tloc=&p_ploc=&pg=1&p_tac=&ti=31&pt=10&ch=357&rl=43.

[TAC] Texas Administrative Code § 358.2. 2012. Available from: https://texreg.sos.state.tx.us/public/readtac$ext.TacPage?sl=R&app=9&p_dir=&p_rloc=&p_tloc=&p_ploc=&pg=1&p_tac=&ti=31&pt=10&ch=358&rl=2.

[TCEQ] Texas Commission on Environmental Quality. 2010. Procedures to implement the Texas Surface Water Quality Standards. Available from: https://www.tceq.texas.gov/downloads/permitting/water-quality-standards-implementation/june-2010-ip.pdf.

[TCPA] Texas Comptroller of Public Accounts. 2012. The impact of the 2011 drought and beyond. Austin (Texas): Texas Comptroller of Public Accounts. Report #96-1794. 14 p. Available from: https://drought.unl.edu/archive/assessments/TX-comptroller-2012.pdf.

The Nature Conservancy. 2009. Indicators of Hydrologic Alteration Version 7.1 User’s Manual. Available from: https://www.conservationgateway.org/ConservationPractices/Freshwater/EnvironmentalFlows/MethodsandTools/IndicatorsofHydrologicAlteration/Documents/IHAV7.pdf.

Thomas ED, Venkataraman K, Chraibi V, Kannan N. 2019. Hydrologic trends in the Upper Nueces River Basin of Texas—implications for water resource management and ecological health. Hydrology. 6(1):1-24. Available from: https://doi.org/10.3390/hydrology6010020.

[USGS] United States Geological Survey. 2021. LCMAP Viewer. Available from: https://eros.usgs.gov/lcmap/viewer/index.html.

Venkataraman K, Tummuri S, Medina A, Perry J. 2016. 21stcentury drought outlook for major climate divisions of Texas based on CMPI5 multimodel ensemble: Implications for water resource management. Journal of Hydrology. 534:300-316. Available from: https://doi.org/10.1016/j.jhydrol.2016.01.001.

Vicente-Serrano SM, Begueria S, Lopez-Moreno JI. 2010. A multiscalar drought index sensitive to global warming: the standardized precipitation evapotranspiration index. Journal of Climate. 23(7):1696-1718. Available from: https://doi.org/10.1175/2009JCLI2909.1.

Vicente-Serrano SM, Lopez-Moreno JI, Begueria S, Lorenzo-Lacruz J, Azorin-Molina C, Moran-Tejada E. 2012. Accurate computation of a streamflow drought index. Journal of Hydrologic Engineering. 17(2):318-332.

Vorosmarty CJ, McIntyre PB, Gessner MO, Dudgeon D, Prusevich A, Green P, Glidden S, Bunn SE, Sullivan SA, Liermann CR, et al. 2010. Global threats to human water security and river biodiversity. Nature. 467(7315):555-561. Available from: https://doi.org/10.1038/nature09440.

Wahl T, Jain S, Bender K, Meyers SD, Luther ME. 2015. Increasing risk of compound flooding from storm surge and rainfall for major US cities. Nature Climate Change. 5: 1093-1097. Available from: https://doi.org/10.1038/nclimate2736.

Wilcox BP, Tauce PI, Munster CL, Owen MK, Mohanty BP, Sorenson JP, Bazan R. 2008. Subsurface stormflow is important in semiarid karst shrublands. Geophysical Research Letters. 35(10):1-6. Available from: https://doi.org/10.1029/2008GL033696.

Wilcox BP, Huang Y. 2010. Woody plant encroachment paradox: Rivers rebound as degraded grasslands convert to woodlands. Geophysical Research Letters. 37(7):1-5. Available from: https://doi.org/10.1029/2009GL041929.

Xie J, Liu X, Wang K, Yang T, Liang K, Liu C. 2020. Evaluation of typical methods for baseflow separation in the contiguous United States. Journal of Hydrology. 583:124628. Available from: https://doi.org/10.1016/j.jhydrol.2020.124628.

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