Characterization of organic precursors in DBP formation and AOC in urban surface water and their fate during managed aquifer recharge

Water scarcity commonly motivates managed aquifer recharge projects, but other factors can motivate recharge efforts, including in relatively water-rich areas. Surface water quality regulation has been a major driving force behind a large-scale recharge project in development in Virginia’s Coastal Plain region, where nutrient pollution from agricultural and urban sources has degraded the Chesapeake Bay’s ecosystems, leading state and federal regulators to require dischargers to reduce their nutrient contributions to the watershed over time. Hampton Roads Sanitation District is pursuing the Sustainable Water Initiative for Tomorrow, an innovative, multi-benefit initiative designed to address both nutrient pollution in the Chesapeake Bay watershed and regional groundwater overdraft in the Coastal Plain. When fully implemented, the initiative is expected to recharge approximately 100 million gallons per day of drinking-water quality, treated municipal wastewater into the Potomac Aquifer System through injection facilities located at five of the District’s wastewater treatment plants. As a result, the District expects to reduce its nutrient discharges from those plants by approximately 90%, enabling it to meet its own mandated nutrient limits while also generating nutrient credits that it can trade to other dischargers. Modeling suggests that the initiative will increase regional water pressure within the confined aquifer system, helping to combat groundwater overdraft and its negative impacts, including aquifer compaction and related land subsidence, falling water levels in wells, and saltwater intrusion. This case study provides insights into the influence of institutional context on managed aquifer recharge and on multi-benefit water resource projects more generally.

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Using Heat as a Tracer to Detect the Development of the Recharge Bulb in Managed Aquifer Recharge Schemes

Hydrology ◽

10.3390/hydrology9010014 ◽

2022 ◽

Vol 9 (1) ◽

pp. 14

Author(s):

Esteban Caligaris ◽

Margherita Agostini ◽

Rudy Rossetto

Keyword(s):

Surface Water ◽

Dimensional Space ◽

Three Dimensional ◽

Winter Season ◽

Managed Aquifer Recharge ◽

Two Dimensions ◽

Quasi Equilibrium ◽

Aquifer Recharge ◽

Groundwater Temperature ◽

Infiltration Basin

Managed Aquifer Recharge (MAR), the intentional recharge of aquifers, has surged worldwide in the last 60 years as one of the options to preserve and increase water resources availability. However, estimating the extent of the area impacted by the recharge operations is not an obvious task. In this descriptive study, we monitored the spatiotemporal variation of the groundwater temperature in a phreatic aquifer before and during MAR operations, for 15 days, at the LIFE REWAT pilot infiltration basin using surface water as recharge source. The study was carried out in the winter season, taking advantage of the existing marked difference in temperature between the surface water (cold, between 8 and 13 °C, and in quasi-equilibrium with the air temperature) and the groundwater temperature, ranging between 10 and 18 °C. This difference in heat carried by groundwater was then used as a tracer. Results show that in the experiment the cold infiltrated surface water moved through the aquifer, allowing us to identify the development and extension in two dimensions of the recharge plume resulting from the MAR infiltration basin operations. Forced convection is the dominant heat transport mechanism. Further data, to be gathered at high frequency, and modeling analyses using the heat distribution at different depths are needed to identify the evolution of the recharge bulb in the three-dimensional space.

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Effect of Surface Water Level Fluctuations on the Performance of Near-Bank Managed Aquifer Recharge from Injection Wells

Water ◽

10.3390/w13213013 ◽

2021 ◽

Vol 13 (21) ◽

pp. 3013

Author(s):

Peipeng Wu ◽

Jean-Christophe Comte ◽

Lijuan Zhang ◽

Shuhong Wang ◽

Bin Chang

Keyword(s):

Surface Water ◽

Water Level ◽

Penetration Depth ◽

Managed Aquifer Recharge ◽

Groundwater Table ◽

Water Level Fluctuation ◽

Water Level Fluctuations ◽

Level Fluctuation ◽

Aquifer Recharge ◽

Average Travel Time

Managed aquifer recharge operations are often conducted in near-bank areas to regulate water resources or reduce seawater intrusion. Yet little is known about the influence of surface water level fluctuations at different temporal scales on MAR performance. A generalized conceptual model was developed based on an investigation site in Western China as a basis to simulate the response surface water level fluctuations on the water table, artificially recharged water lens (formed by the artificially recharged water), groundwater flow paths and average travel times (which is an important control on how quickly contaminants are flushed out of aquifers), and the discharge of the artificially recharged aquifer during the surface water level fluctuation. The results showed a fluctuating groundwater table in the artificially recharged near-bank aquifer under the influence of surface water level fluctuations. The peak values of the increment of the groundwater table induced by artificial recharge decreased with the increase of the period and amplitude of surface water level fluctuation, but the trough values of the increment of water table increases with that. The penetration depth of surface water into the aquifer with a fluctuating surface water level leads to a decreasing increment of the groundwater table which follows a power law. The fluctuating surface water level leads to dynamic changes of artificially recharged water lens morphology and a thinner artificially recharged water lens. A mixing zone of recharged water and ambient water could be found in the artificially recharged near-bank area, which is expected to lead to modifications in the geochemical conditions in the artificially recharged near-bank aquifer. A longer period of surface water level fluctuation leads to a longer average travel time, but the larger penetration depth of surface water and amplitude lead to a shorter average travel time. The peak discharge of the near-bank aquifer was found to decrease with the period of surface water level fluctuation, but it increases with penetration depth and amplitude. This study is important in providing insights into the performance of near-bank managed aquifer recharge with respect to surface water level fluctuation.

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Potential Benefits of Managed Aquifer Recharge MAR on the Island of Gotland, Sweden

Water ◽

10.3390/w11102164 ◽

2019 ◽

Vol 11 (10) ◽

pp. 2164 ◽

Cited By ~ 2

Author(s):

Dahlqvist ◽

Sjöstrand ◽

Lindhe ◽

Rosén ◽

Nisell ◽

...

Keyword(s):

Surface Water ◽

Water Supply ◽

Water Availability ◽

Managed Aquifer Recharge ◽

Aquifer Recharge ◽

Groundwater Abstraction ◽

Local Conditions ◽

Management Measures ◽

Supply Potential ◽

Alternative Water

The Island of Gotland (3000 km2), east of mainland Sweden, suffers from insufficient water availability each summer. Thin soils and lack of coherent reservoirs in the sedimentary bedrock lead to limited reservoir capacity. The feasibility of Managed Aquifer Recharge (MAR) is explored by identifying suitable areas and estimating their possible contribution to an increased water availability. MAR is compared to alternative water management measures, e.g., increased groundwater abstraction, in terms of costs and water availability potential. Results from GIS analyses of infiltration areas and groundwater storage, respectively proximity to surface water sources and surface water storage were classified into three categories of MAR suitability. An area of ca 7700 ha (2.5% of Gotland) was found to have good local conditions for MAR and an area of ca 22,700 ha (7.5% of Gotland) was found to have moderate local conditions for MAR. These results reveal the MAR potential on Gotland. The water supply potential of MAR in existing well fields was estimated to be about 35% of the forecasted drinking water supply and 7% of the total water demand gap in year 2045. It is similar in costs and water supply potential to increased surface water extraction.

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