Impingement and Entrainment at SWRO Desalination Facility Intakes

  • Timothy W. HoganEmail author
Conference paper
Part of the Environmental Science and Engineering book series (ESE)


Seawater desalination intakes have potential to negatively impact marine life. The principal impacts of concern are broadly categorized into impingement and entrainment (I&E). Each represents an interaction between the marine organisms in the source water body and the intake screening technology used at the desalination facility. Impingement is the entrapment of larger organisms against the screen mesh by the flow of the withdrawn water. Entrainment is the passage of smaller organisms through the screening mesh. Concern over the impacts of I&E has formed the basis of a major portion of the environmental regulation of seawater intakes in the U.S. for power generation and other industrial uses. In addition, the impacts of I&E at seawater desalination intakes is growing as a global environmental concern. The withdrawal of seawater for desalination has impacts that cannot be eliminated; however, they can be minimized. There are well-recognized approaches for predicting the potential for I&E, for documenting the magnitude of I&E, and for assessing the impacts of I&E on natural populations. More importantly, the body of knowledge surrounding I&E and the means for minimizing its impacts is extensive. Although some impacts are unavoidable, various technological and operational methods, many of which have undergone extensive laboratory and field evaluation, are available and proven to improve the protection of marine life at desalination facility intakes. This chapter reviews the biology of I&E at seawater intakes, the sampling approaches for assessing and quantifying I&E, the methods for predicting the potential for I&E, the methods for assessing the impact of I&E on natural populations, and the common approaches and technologies available for minimizing I&E at seawater intakes.


Early Life Stage Intake Screening Seawater Desalination Impingement Mortality Organism Abundance 
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Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Alden Research LaboratoryHoldenUSA

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