A simple thermal mapping method for seasonal spatial patterns of groundwater–surface water interaction

Abstract. The interaction between groundwater and surface water along the Tambo and Nicholson rivers, southeast Australia, was investigated using 222 Rn, Cl, differential flow gauging, head gradients, electrical conductivity (EC) and temperature profiles. Head gradients, temperature profiles, Cl concentrations and 222 Rn activities all indicate higher groundwater fluxes to the Tambo River in areas of increased topographic variation where the potential to form large groundwater-surface water gradients is greater. Groundwater discharge to the Tambo River calculated by Cl mass balance was significantly lower (1.48 × 10 4 to 1.41 × 10 3 m 3 day −1 ) than discharge estimated by 222 Rn mass balance (5.35 × 10 5 to 9.56 × 10 3 m 3 day −1 ) and differential flow gauging (5.41 × 10 5 to 6.30 × 10 3 m 3 day −1 ) due to bank return waters. While groundwater sampling from the bank of the Tambo River was intended to account for changes in groundwater chemistry associated with bank infiltration, variations in bank infiltration between sample sites remain unaccounted for, limiting the use of Cl as an effective tracer. Groundwater discharge to both the Tambo and Nicholson rivers was the highest under high-flow conditions in the days to weeks following significant rainfall, indicating that the rivers are well connected to a groundwater system that is responsive to rainfall. Groundwater constituted the lowest proportion of river discharge during times of increased rainfall that followed dry periods, while groundwater constituted the highest proportion of river discharge under baseflow conditions (21.4 % of the Tambo in April 2010 and 18.9 % of the Nicholson in September 2010).

Section: N P Unland Et Al: Investigating the Spatio-temporal Variamentioning

confidence: 99%

Investigating the spatio-temporal variability in groundwater and surface water interactions: a multi-technique approach

Unland

Cartwright

Andersen

et al. 2013

“…Specific to field data availability and analytical solutions data requirements, they were applied in several case studies to evaluate temperature profiles (e.g. Schmidt et al, 2006Schmidt et al, , 2007Anibas et al, 2011) or temperature time series (e.g. Keery et al, 2007; Published by Copernicus Publications on behalf of the European Geosciences Union.…”

Section: Introductionmentioning

confidence: 99%

Sand box experiments to evaluate the influence of subsurface temperature probe design on temperature based water flux calculation

Munz

Oswald

Schmidt

2011

Abstract. Quantification of subsurface water fluxes based on the one dimensional solution to the heat transport equation depends on the accuracy of measured subsurface temperatures. The influence of temperature probe setup on the accuracy of vertical water flux calculation was systematically evaluated in this experimental study. Four temperature probe setups were installed into a sand box experiment to measure temporal highly resolved vertical temperature profiles under controlled water fluxes in the range of ±1.3 m d −1 . Pass band filtering provided amplitude differences and phase shifts of the diurnal temperature signal varying with depth depending on water flux. Amplitude ratios of setups directly installed into the saturated sediment significantly varied with sand box hydraulic gradients. Amplitude ratios provided an accurate basis for the analytical calculation of water flow velocities, which matched measured flow velocities. Calculated flow velocities were sensitive to thermal properties of saturated sediment and to temperature sensor spacing, but insensitive to thermal dispersivity equal to solute dispersivity. Amplitude ratios of temperature probe setups indirectly installed into piezometer pipes were influenced by thermal exchange processes within the pipes and significantly varied with water flux direction only. Temperature time lags of small sensor distances of all setups were found to be insensitive to vertical water flux.

“…The method has proved to be reliable (Lautz, 2010;Ferguson and Bense, 2011), not least because gathering of thermal data, parameter estimation, establishment of model boundary conditions and calibration are fairly simple (Anibas et al, 2009). Different methodologies have been applied (Anderson, 2005;Kalbus et al, 2006), but most commonly exchange rates have been quantified by inverse modeling of temperature profiles measured in riverbeds Anibas et al, 2009Anibas et al, , 2011. Various studies were performed on sites where the riverbed is composed of sand or gravel (Conant, 2004;Anibas et al, 2011); applications on sites dominated by peat soils are scarce.…”

mentioning

confidence: 99%

“…Different methodologies have been applied (Anderson, 2005;Kalbus et al, 2006), but most commonly exchange rates have been quantified by inverse modeling of temperature profiles measured in riverbeds Anibas et al, 2009Anibas et al, , 2011. Various studies were performed on sites where the riverbed is composed of sand or gravel (Conant, 2004;Anibas et al, 2011); applications on sites dominated by peat soils are scarce. The application of C. Anibas et al: A hierarchical approach on groundwater-surface water interaction 2331 the thermal method represents a point estimate (Becker et al, 2004); the spatial interpolation of distributed sets of these estimates is described in the literature (Schmidt et al, 2007;Anibas et al, 2011).…”

mentioning

confidence: 99%

A hierarchical approach on groundwater-surface water interaction in wetlands along the upper Biebrza River, Poland

Anibas

Verbeiren

Buis

et al. 2012

Abstract. As recognized in the European Water Framework Directive, groundwater-dependent wetlands and their diverse ecosystems have important functions which need to be protected. The vegetation in such habitats is often dependent on quality, quantity and patterns of river discharge and groundwater-surface water interaction on a local or reach scale. Since groundwater-surface water exchange studies on natural rivers and wetlands with organic soils are scarce, more functional analysis is needed. To this end we combined different field methods including piezometer nests, temperature as tracer and seepage meter measurements. Some of these measurements were used as inputs and/or as validation for the numerical 1-D heat transport model STRIVE. In transient mode the model was used to calculate spatially distributed vertical exchange fluxes from temperature profiles measured at the upper Biebrza River in Poland over a period of nine months. Time series of estimated fluxes and hydraulic head gradients in the hyporheic zone were used to estimate the temporal variability of groundwater-surface water exchange.This paper presents a hierarchical approach for quantifying and interpreting groundwater-surface water interaction in space and time. The results for the upper Biebrza show predominantly upward water fluxes, sections of recharge, however, exist along the reach. The fluxes depend more on hydraulic gradients than on riverbed conductivity. This indicates that the fluvio-plain scale is required for interpreting the exchange fluxes, which are estimated on a local scale. The paper shows that a conceptual framework is necessary for understanding the groundwater-surface water interaction processes, where the exchange fluxes are influenced by local factors like the composition of the riverbed and the position of the measurement on a local scale, and by regional factors like the hydrogeology and topography on a fluvio-plain scale. The hierarchical methodology increases the confidence in the estimated exchange fluxes and improves the process understanding. The accuracy of the measurements and related uncertainties, however, remain challenges for wetland environments. Gaining quantitative information on groundwatersurface water interaction can improve modeling confidence and as a consequence helps to develop effective procedures for management and conservation of valuable groundwater dependent wetlands.