The 390m long roller compacted concrete (RCC) storage dam will be located 60km southeast of Muscat. With a height of 73.6m and 100Mm3 storage capacity, the Wadi Dayqah project will provide approximately 35Mm3 of water a year – around 10Mm3 for villages down the wadi stream for agricultural purpose, with a further 5.7Mm3 and 19.3Mm3 for drinking water and domestic purposes in Qurayat and Muscat Governorate respectively, according to local reports.
Critics of the project have however suggested that the benefits of building the dam would not outweigh the costs. Although water flow in Wadi Dayqah is perennial in its upper and middle reaches, quantities of water are not guaranteed from year to year. It has also been pointed out that Oman has some of the highest possible flood maxima in the world, which means that huge quantities of alluvium, including boulders and rocks, could have an impact on the project.
The project’s owners, Sultanate of Oman Ministry of Regional Municipalities, Environment and Water Resources, has however stressed that the scheme is needed as it calculated only 10% of the water flow to be encompassed by the dam benefited agriculture, while the rest was lost to sea.
Work on the project will start in early summer this year, with a scheduled completion date of late 2008.