EghtesadOnline: Construction of two inflatable rubber dams will be completed by March in northern Mazandaran Province, the deputy for planning and development at the Mazandaran Regional Water Company said.
“The rubber of Larim Dam on Siahrood River in Juybar County has been set up and the rubber for Pazevar Dam on Babolrood River, Babolsar County, is being installed,” Heydar Davoudian was quoted as saying by the Energy Ministry news portal Paven.
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 exhibits 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, according to Financial Tribune.
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.
Referring to the rubber dams as one of the most useful and inexpensive ways to contain surface water, Davoudian said: “These dams help prevent salt water intrusion into fresh water areas, and are used to divert water for farming.”
Water retention for aquifer recharge, enabling fish passage past diversion works, protecting low-lying coastal areas from tidal flooding, and for sewage retention/separation during flood events are other usages of such dams.
No Sediment Accumulation
Davoudian described the main advantage of rubber dams as 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.
“No sediment will pile up behind these dams. Useful life of these structures is usually between 25 and 30 years and after that, the dams can bus used again by replacing the rubber,” he added.
There are more than 2000 inflatable rubber dams around the world. Durability can be excellent: recently, a 35-year-old dam in eastern Ontario, Canada, was replaced, and while still functional in both freezing winter conditions when it was air filled, and water filled in summer, it was deemed to have served its useful life, and was replaced.
“The first rubber dam in Mazandaran was built in 1996 and currently five rubber dams with total storage capacity of four million cubic meters are operational in the province,” the official said.
Pazevar and Larim dams each have a capacity of six million cubic meters, and their water will be used to farm 6,000 hectares in the region.
Inflatable rubber dams have been used as water control structures for more than 50 years. They are relatively inexpensive and have versatile structures capable of creating pondage and/or controlling flow in a particular watercourse.
Mazandaran Province is located along the southern coast of the Caspian Sea and adjacent to the Central Alborz mountain range.
It 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.