Environmental impact and impact assessment of seawater desalination
Sabine Lattemann, Thomas Höpner
Institute for Chemistry and Biology of the Marine Environment (ICBM), University of Oldenburg, Carl von Ossietzky Str. 9-11, 26111 Oldenburg, Germany email: email@example.com
Received 29 January 2007; accepted 13 March 2007
Abstract Desalination ofseawater accounts for a worldwide water production of 24.5 million m3 /day. A “hot spot” of intense desalination activity has always been the Arabian Gulf, but other regional centers of activity emerge and become more prominent, such as the Mediterranean Sea and the Red Sea, or the coastal waters of California, China and Australia. Despite the many benefits the technology has to offer, concerns riseover potential negative impacts on the environment. Key issues are the concentrate and chemical discharges to the marine environment, the emissions of air pollutants and the energy demand of the processes. To safeguard a sustainable use of desalination technology, the impacts of each major desalination project should be investigated and mitigated by means of a project- and location-specificenvironmental impact assessment (EIA) study, while the benefits and impacts of different water supply options should be balanced on the scale of regional management plans. In this context, our paper intends to present an overview on present seawater desalination capacities by region, a synopsis of the key environmental concerns of desalination, including ways of mitigating the impacts of desalination onthe environment, and of avoiding some of the dangers of the environment to desalination. Keywords: Seawater desalination; Environmental impact; Impact assessment; EIA; Marine environment; Brine; Wastewater; Energy; Chemicals; Chlorine; Antiscalants
1. Introduction Many semi-arid and arid regions in the world suffer from structural water shortages, which impose constraints on economic, social andhuman development. Furthermore, severe ecosystem damage may be caused if water abstraction rates exceed natural renewal rates, leading to a depletion
or salinization of stocks and land desertification. To meet the growing demand and to avert damage from ecosystems and aquifers, water management regimes have to increasingly implement non-typical technologies and sourcewaters. Treated wastewater presently accounts for 5%, brackish water for 22% and seawater for 58% of the water produced by desalination technologies . Desalination of seawater is thus the technology predominantly used for alleviating
Presented at the conference on Desalination and the Environment. Sponsored by the European Desalination Society and Center for Research and Technology Hellas(CERTH), Sani Resort, Halkidiki, Greece, April 22–25, 2007.
0011-9164/06/$– See front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.desal.0000.00.000
S. Lattemann, T. Höpner / Desalination 220 (2008) 1–15
the problem of water scarcity in coastal regions. It accounts for a worldwide production capacity of 24.5 million m3/day. Although desalination of seawater offers arange of human health, socio-economic, and environmental benefits by providing a seemingly unlimited, constant supply of high quality drinking water without impairing natural freshwater ecosystems, concerns are raised due to potential negative impacts. These are mainly attributed to the concentrate and chemical discharges, which may impair coastal water quality and affect marine life, and airpollutant emissions attributed to the energy demand of the processes. The list of potential impacts can be extended, however, the information available on the marine discharges alone  indicates the need for a comprehensive environmental evaluation of all major projects. In order to avoid an unruly and unsustainable development of coastal areas, desalination activity furthermore should be integrated...