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Precipitation-Runoff and Streamflow-Routing Modeling as a Foundation for Water-Quality Simulation in the Willamette River Basin, Oregon
Published in Antonius Laenen, David A. Dunnette, River Quality, 2018
Antonius Laenen, John C. Risley
Gain-loss measurements identify (1) the seasonality of groundwater inflow to the main stem, and (2) the magnitude and general location of hyporheic flow that can occur. Measurements made in summer indicate little or no groundwater contribution, and measurements made in spring indicate an approximate 2000 ft3/s groundwater contribution between RM 195.0 and RM 55.0 on the Willamette River. The upper Willamette River between RM 195.0 and 140.0 is a system of braided streams with many islands, sloughs, and gravel bars. In this reach of river, gain-loss measurements showed as much as 1000 ft3/s; 15% of the total river flow can be considered to be in the hyporheic flow zone. The word “hyporheic” means “under river,” and the hyporheic zone is defined as the subsurface area where stream water and groundwater mix. From a water-quality standpoint, important chemical and biological processes occur in the hyporheic zone. Large increases of 9 and 7% in Willamette River flow were also noted adjacent to the alluvial fans of the Santiam and Molalla Rivers, respectively.
Water resources science
Published in Mohammad Albaji, Introduction to Water Engineering, Hydrology, and Irrigation, 2022
Throughout the course of the river, the total volume of water transported downstream will often be a combination of the visible free water flow together with a substantial contribution flowing through sub-surface rocks and gravels that underlie the river and its floodplain called the hyporheic zone. For many rivers in large valleys, this unseen component of flow may greatly exceed the visible flow. The hyporheic zone often forms a dynamic interface between surface water and true ground-water receiving water from the groundwater when aquifers are fully charged and contributing water to groundwater when groundwaters are depleted. This is especially significant in karst areas where pot-holes and underground rivers are common.
Surface water–ground Water Interactions and Modeling Applications
Published in Calvin C. Chien, Miguel A. Medina, George F. Pinder, Danny D. Reible, Brent E. Sleep, Chunmiao Zheng, and Sediment, 2003
Calvin C. Chien, Miguel A. Medina, George F. Pinder, Danny D. Reible, Brent E. Sleep, Chunmiao Zheng
The structure and characteristics of the biological community that lives within the hyporheic zone is not well defined. This is due, in part, to the general difficulties in obtaining good samples from this zone. Therefore, the zone has not been as well investigated as other components of aquatic systems. Traditionally, scientists have considered only the upper few inches (typically only the upper 6 in. or 15cm ) as the biologically active zone in most aquatic systems, but investigations have found a diverse community of organisms that inhabit substrate at depths greater than 6 in. or 15cm (Williams and Hynes, 1974). Biological members of the hyporheic zone include permanent members, which complete their entire life cycle within the zone, and transient members, which spend only a portion of their life cycle within this zone. Permanent members include species of rotifers, oligocheates, copepods, ostracods, cladocerans, and other crustaceans. Transient members include species typically found as members of the streambed benthos that migrate as early instar larval stages to avoid disturbance (e.g., high river flows) (Williams, 1987) or stress (e.g., temperature extremes) (Harper and Hynes, 1970). In addition to serving as habitat and refuge for groups of organisms, the hyporheic zone can also be an area of significant nutrient recycling within aquatic systems (Williams, 2000).
A critical review of microplastic pollution in urban freshwater environments and legislative progress in China: Recommendations and insights
Published in Critical Reviews in Environmental Science and Technology, 2021
Yuyao Xu, Faith Ka Shun Chan, Jun He, Matthew Johnson, Christopher Gibbins, Paul Kay, Thomas Stanton, Yaoyang Xu, Gang Li, Meili Feng, Odette Paramor, Xubiao Yu, Yong-Guan Zhu
The transportation of microplastics may be critical to assessing and understanding health risks. Because of their lipophilic features and high surface area to volume ratio, which enable them to absorb chemical pollutants, including persistent organic pollutants (e.g. pesticides and antibiotics), as well as pathogenic bacteria, fungi and viruses (Zou et al., 2017), microplastics pose risks to ecosystems and human health. Additionally, toxic plastic additives, such as flame retardants, pigment and ultraviolet stabilizer can be release once plastics are in the freshwater environment (Gabriella, 2019). Risk partly depends storage dynamics. For instance, exposure of benthic organisms to microplastics depends how much material may be stored within the bed matrix, and the duration of residence here before being remobilised during high flows (van Cauwenberghe et al., 2015). Residence times are likely to be longer in stable sediments that are infrequently disturbed, so lentic environments can act as a longer term store for microplastics than fluvial environments (Eerkes-Medrano et al., 2015). Movement of microplastics can also be altered by absorption of other materials or colonization by microbial communities, changing particle density and causing microplastics to settle more easily (Fan et al., 2019; Lin et al., 2018; Wang et al., 2018). Research foci are now changing from simple assessment of loads to efforts understand pathways, including those in the subsurface (i.e. via hyporheic zone and groundwater), although such work still remains limited in China (Su et al., 2016; Zhao et al., 2015).
Oxygenation and hydrologic controls on iron and manganese mass budgets in a drinking-water reservoir
Published in Lake and Reservoir Management, 2019
Zackary W. Munger, Cayelan C. Carey, Alexandra B. Gerling, Jonathan P. Doubek, Kathleen D. Hamre, Ryan P. McClure, Madeline E. Schreiber
Although we solved for groundwater/runoff inflow using the water balance (equation 1), and installed 4 shallow wells around the reservoir to measure metals concentrations in shallow groundwater (Munger 2016), we did not use Qgwr to calculate groundwater metals loading for several reasons: (1) Our estimate of groundwater inflow is combined with surface runoff and other unmeasured flows, so it is not specific to groundwater; (2) previous studies have documented that shallow groundwater chemistry is not indicative of chemistry that actually enters lakes/reservoirs due to spatial heterogeneity of concentrations (Brock et al. 1982); (3) three-dimensional flowpaths of groundwater to surface-water bodies are complex and difficult to map without extensive field monitoring and modeling (Lewandowski et al. 2015, Rosenberry et al. 2015); (4) redox conditions can change rapidly across the sediment–water interface (i.e., the hyporheic zone), and strongly control the transport of redox-sensitive metals (Harvey and Fuller 1998, Brown et al. 2007); and (5) the sediment–water interface is highly reactive, affecting transport of metals and other elements that can react with surfaces of minerals and organic matter (Lewandowski et al. 2015). Thus, to calculate the metals budget, we assumed that groundwater that entered the reservoir subsequently mixed and became integrated with sediment pore water.
State of future water regimes in the world’s river basins: balancing the water between society and nature
Published in Critical Reviews in Environmental Science and Technology, 2019
Managing groundwater aquifers is an important approach for enhancing water security in the world’s river basins. Discharge and recharge of groundwater aquifers are often a natural phenomenon. Groundwater discharge improves water quality, and support ecosystems by mobilizing the base flow conditions (Heathwaite, 2010). More than 90% of global available freshwaters including the base flow of rivers, lakes and wetlands during the periods of low or no rainfalls are maintained by natural hydrological patterns of groundwater (Gulbhile & Deshmukh, 2011). However, the natural discharge of groundwater has become unsustainable due to over-withdrawals. Groundwater alone makes one third of the global freshwater withdrawals disrupting natural recharge capacity and base flows (Taylor et al., 2013). The disruption of base flows has affected connectivity between river-channel and bank sediments, which create a mixing zone with subsurface water, the hyporheic zone, and consequently altering biogeochemical exchange between groundwater-surface water interface (Heathwaite, 2010; Sophocleous, 2002). Further, intensive irrigation programs in dry river basins consume 70-90% global freshwaters. The large-scale use of freshwaters has led to a significant depletion of groundwater in regions mostly relied on groundwater-dependent irrigation system (Aeschbach-Hertig & Gleeson, 2012; Doll, Schmied, Schuh, Portmann, & Eicker, 2014; MacDonald et al., 2016) (also see Figure 6a and b). Balancing ecological flow requirements of rivers with water demand and ensuring that the groundwater extraction does not exceed natural recharge, is a key for managing groundwater resources in river basins (Gober & Kirkwood, 2010). Whilst our knowledge in the natural hydrological patterns of groundwater is still limited, developing better technologies for monitoring groundwater aquifers from sub-surface environment to the deep below in the Earth's crust is crucial (Foster, Chilton, Nijsten, & Richts, 2013). Study suggests that monitoring data of base flow to river runoff ratios are useful for estimating the relative contribution of groundwater to river runoff (Zektser & Loaiciga, 1993). Knowing the ratios of base flow to river run off can help develop an integrated hydrological model and improved water security. Lately, the Satellite Gravity Recovery and Climate Experiment (GRACE) and integrated hydrological model (e.g. MOSHISE) together are used to estimate the volume of groundwater storage and the nature of flow in the aquifers (Brouyvre, Carabin, & Dassargues, 2004; Groelick & Zheng, 2015; MacDonald et al., 2016; Taylor et al., 2013).