International Desalination Symposium: Desalination and the Gulf

 

 

13 January 2011

In December 2010, 360 Environmental presented at the IDA Symposium in Bahrain (Desalination and the Gulf: The Relationship between the Environment and Meeting the Region’s Water Needs).  For the first time, this symposium brought stakeholders from throughout the Gulf region together to explore the issues and facilitate discussion on the relationship between desalination and the environmental health of the Arabian Gulf to shape a path to ensure the Gulf’s well-being for future generations. The conference was well attended and a great opportunity to contribute to the International Desalination Association network.

The presentation delivered was Mitigation Approaches to Address Impacts of Saline Discharges in the Marine Environment.  The paper explored the mitigation approaches to address the risk of saline impacts associated with desalination.  An adequate understanding of the long-term fate of seawater concentrate and how marine and freshwater environments respond continues to be lacking and such fundamental information is required.  For large seawater desalination projects, development and use of site-specific models and near-field dispersion monitoring are warranted for improved preconstruction assessment (Khan et al, 2007). Because the environmental impact of plant discharges is site specific and may vary from benign to significant depending on plant size and type, salinity tolerance, flora and fauna abundance, and hydrodynamic conditions in the area of discharge, generic designs or standards are not the solution.  Approval for Australian plants requires detailed environmental impact assessments that can incorporate whole-effluent toxicity testing, baseline marine monitoring for up to two years, sludge treatment, and renewable energy.  Although there are global guidelines, legislation, and leading-edge desalination plants, environmental management continues to vary significantly.  

The Arabian Gulf is a semi-enclosed sea, connected to the Gulf of Oman through the narrow Strait of Hormuz (56 km wide), with an average depth of 35m (up to 60-100m in parts).  The Kuwait Institute for Scientific Research (2010) presented that the salinity in the Gulf ranges from 36.3-47.6 g/L and the circulation residence times are 2-5 years.  As freshwater inflow reduces (some 110 km³/year - Rise 2006) and industrial discharges increase (>7.3 km³ per year -Abdel-Jawad 2010) anthropogenic and environmental considerations for the waters of the Gulf will come into closer focus.  The conference heard that blooms of toxic marine phytoplankton are increasing in frequency, intensity and distribution in the Arabian Gulf. Perhaps the blooms are an early warning sign that more knowledge is required to understand and therefore protect this valuable marine ecosystem.