Aquifer Storage and Recovery (ASR) is defined as the injection of freshwater surpluses in aquifers using wells, followed by recovery in times of demand using the same well. It can be an efficient technique to store freshwater surpluses for times of demand. However, in brackish-saline aquifers the density-driven flow can result in limited recoverability of freshwater: injected freshwater is pushed up towards the top of the aquifer (buoyancy effect) and brackish/saline water eventually enters the lower well section.
The recovery efficiency (RE) – the part of the recovered injected water that is of satisfactory quality – will therefore be lower than 100% in brackish/saline aquifers. It is of utmost importance to have an indication of this RE prior to construction/planning of any ASR system, since it determines the water supply and business case of the system. The RE, however, depends on the aquifer properties (such as thickness, permeability, salinity) and operational parameter (pumping rates, duration of injection/storage/recovery periods).
This tool can quickly estimate the performance of ASR, based on commonly available hydrogeological and operational parameters a priori. It is therefore a vital decision-support tool in the field of ASR. Typically, unviable set-ups will be recognized efficiently and can be avoided, so that more focus can be given to promising cases.
How does it work?
This tool is based on very valuable work in the field of ASR performance estimation by Ward et al. (2009) and Bakker (2010). Both publicationsdemonstrated different approaches to estimate ASR feasibility:
- Ward et al. (2009): Use of the sum different dimensionless performance indicators. According to a large number of scenarios, a performance indication (qualitative) was given to this sum.
- Bakker (2010): Use of a Depuit-based approach employing interfaces to calculate the moment that the interface between fresh and brackish/saltwater (the “toe”) reaches the lower well section.
This tool requires only common hydrogeological information (aquifer thickness, hydraulic conductivity, hydr. Gradient, salinity) and operational information (pumping rate during injection, duration of injection/storage/recovery periods).
Implementation of the tool involves the following steps:
- Gather required hydrogeological and operational information.
- Page 1: select the ratio between injection/storage/recovery phases.
- Insert the exact duration of the injection or storage or recovery period.
- Page 2: insert the volume that is stored (i.e., injected).
- Insert the aquifer properties derived from characterisation study are based on estimates.
- Calculate results.
There is as yet no training and support available for ASR Performance Assessor.
Mentioned in: 3 Publications
Enrolled in: 2 Cases in 1 Country
- Bakker, M., 2010. Radial Dupuit interface flow to assess the aquifer storage and recovery potential of saltwater aquifers. Hydrogeology Journal, 18(1): 107-115.
- Ward, J.D., Simmons, C.T., Dillon, P.J. and Pavelic, P., 2009. Integrated assessment of lateral flow, density effects and dispersion in aquifer storage and recovery. Journal of Hydrology, 370(1-4): 83-99.
- Zuurbier, K., Bakker, M., Zaadnoordijk, W. and Stuyfzand, P., 2013. Identification of potential sites for aquifer storage and recovery (ASR) in coastal areas using ASR performance estimation methods. Hydrogeology Journal, 21(6): 1373-1383.