The fourth unit of Zahedan Water Desalination Plant in Zahedan, Sistan-Baluchestan Province, was inaugurated Tuesday, managing director of the provincial Water and Wastewater Company said.
"Using reverse osmosis technology the new phase will produce 10,000 cubic meters of safe water a day," Alireza Qasemi was quoted as saying by the Energy Ministry news portal Paven.
The facility in Zahedan desalinates water that is diverted from three big reservoirs in the south of the Sistan Plain called Chah-Nimeh. Surplus water from Hirmand River flows into the three reservoirs through a canal.
The reservoirs have a capacity of 700 million cubic meters of water which must be desalinated before being used.
“The unit will improve access to safe and sustainable water for 58,500 people in the city,” Qasemi said. The phase, five wells and installing 12 km of pipelines cost $3.3 million.
Three reverse osmosis desalination units (total capacity 20,000 cubic meters/day) have been operating to desalinate brackish groundwater since 2003.
Located in one of the most arid areas in southeast Iran with a population of over 600,000, Zahedan’s water consumption needs are largely met from groundwater sources.
Sistan-Baluchestan is the second largest province of Iran, bordering Afghanistan and Pakistan. The region has been struggling with water crises for more than two decades.
In recent years, groundwater is extracted from aquifers at a faster rate than the recharge because of extremely low rainfall (105 mm a year on average), rapid urban development and high population growth rate.
As the water crisis worsens and groundwater resources dry up, using unconventional water resources, namely saline water, has become inevitable, Qasemi noted.
Improving Rural Water Supply
Also on Tuesday a project was launched to supply water to 21 rural areas in Taftan County. With 39 km of transmission lines 5,000 residents will have better access to potable water.
“Last year more than 100,000 residents in 320 villages of Sistan-Baluchestan were supplied piped water,” Qasemi said.
Almost half the population of the underdeveloped region live in rural areas and 250,000 people get drinking water via tankers.
According to the provincial authorities, if water infrastructure does not improve drought, joblessness plus the deteriorating economic conditions will force half a million people to migrate in search of work and a decent livelihood.
Rubber Dam
In related news, Paven said an inflatable rubber dam was inaugurated in the northern Mazandaran Province on Tuesday. Larim Dam on Siahroud River in Jouybar County can hold one million cubic meters of water to feed 4,200 hectares of farmlands in the region.
The first rubber dam in Mazandaran was built in 1996 and six such dams with storage capacity of five million cubic meters are operational in the tourist region located along the southern coast of the Caspian Sea and adjacent to the Central Alborz mountain range.
Inflatable rubber dams are cylindrical rubber fabrics placed across channels, streams and rivers to raise the upstream water level when inflated. The fabric is flexible and yet has good wear-resistance characteristics.
Rubber dams were developed in the early 1950s and are installed in stream and riverbeds, generally being bolted into concrete foundation. There are more than 2000 inflatable rubber dams around the world.
They can be filled with water, air or both. They are inflated by pumping air or water inside the rubber body until the design height or pressure is reached.
Rubber dams are one of the most useful and inexpensive ways to contain surface water. They help prevent salt water intrusion into fresh water areas, and are used to divert water for farming.
Mazandaran is a major producer of farmed fish, and aquaculture provides an important economic addition to traditional dominance of agriculture.
Over 70 kinds of agricultural products are grown in Mazandaran. It meets 40% of domestic demand for rice and 50% of citrus fruits. The province is also the sole domestic kiwi supplier.
The main advantage of rubber dams is having no sediment accumulation. This is a major benefit as it removes the need for dredging, which is costly and possibly harmful for the environment.
