Water Corporation has lodged two separate applications to the Department of Environment Regulation (DER), regarding the management of brackish water and the securing of Denmark’s water supply.
Last year Denmark experienced its second driest year on record, leading to significantly low dam levels.
To increase drinking water supplies, Water Corporation is installing portable desalination units to desalinate water from the Denmark River for the upcoming summer. Brackish, or salty water, is a by-product of the desalination process and is less than 50 per cent of the salt content of seawater.
The DER applications relate to two different options Water Corporation is exploring to manage the brackish water produced by the desalination units.
Although Water Corporation has lodged these applications to DER, a final decision on the preferable option has not yet been made. These applications can be withdrawn at any time.
The first application for DER to assess is the option to add the brackish water to the Southern Seawater Desalination Plant (SSDP) near Binningup. The brackish water will make up a small part of the existing SSDP seawater, which quickly disperses into the ocean.
Members of the SSDP Community Reference Group were recently briefed by Water Corporation on this option.
The second application for DER to assess is the option to store the brackish water at the Albany Wastewater Treatment Plant in three existing storage ponds.
The applications are required to permit Water Corporation to transport the brackish water, which is defined as a non-toxic salt, and to manage on site once it is transported.
Water Corporation is exploring these options as access to the coastline around Denmark itself is very restricted. Transporting the brackish water to the ocean near the town has been ruled out for the immediate term.
Water Corporation is determined to find a solution to manage the brackish water as securing a water supply for the people of Denmark ahead of summer is an important undertaking.
We will liaise with the community and stakeholders to find a solution that enables us to manage the return of brackish water to the environment in an environmentally friendly way, while also keeping in mind the economic cost to our customers.
- Denmark experienced its second driest year on record in 2014, receiving 766.7 mm of rain during the year compared to the average of 1090 mm.
- In June 2015 Denmark received 84.2 mm of rain, which was well below the average for June of 154.3 mm.
- The Bureau of Meteorology has predicted below average rainfall for Denmark throughout the period of July to September 2015.