Will dredging save Gorgan Bay?

February 18, 2022 - 17:32

TEHRAN – More than 35 percent of Gorgan Bay at the south-eastern shore of the Caspian Sea has dried up. Dredging of canals leading to the bay has been announced as one of the solutions, but some experts believe that it needs assessment, considering the topographic conditions of the region.

Covering an area of about 400 square kilometers, the Gulf of Gorgan also known as Gorgan Bay, is located near the cities of Behshahr, Gorgan, and Sari and is separated from the main water body by the Miankaleh peninsula and extends until the Ashuradeh peninsula.

Geological evidence has shown that the Gulf of Gorgan had not yet formed about 2,600 years ago when the water level of the Caspian Sea was 22 meters high, and during the Little Ice Age, at the altitude of 24 meters, the Miankaleh Peninsula began to form and the Gorgan Bay was created.

The ecology of Gorgan Bay is affected by the Caspian Sea, adjacent rivers, and the Miankaleh Peninsula, which play an important role in the growth and reproduction of aquatic, bony, and cartilaginous fish and the attraction of migratory birds.

Therefore, it can be said that Miankaleh Peninsula and Gorgan Bay are environmentally and geographically inseparable.

The bay has a unique, but fragile, biodiversity and not only has valuable cartilaginous fish, white fish, and mullet but also provides a significant share of caviar needed by the country.

But this valuable water basin has been struggling with drought, as the Caspian Sea has dropped by about 25 cm over the past 5 years, which has caused more than 35 percent of Gorgan Bay to dry up.

However, earlier the former deputy director of the Department of Environment, Ahmad Reza Lahijanzadeh, said that a five-year plan has been prepared and announced to the related bodies, to solve the problems of Gorgan Bay and Miankaleh wetland.

The solutions approved for Gorgan Bay are compiled 5 years ago, the water level of the Caspian Sea has dropped by about 25 cm since that time, and the plans such as dredging may no longer be the right solution as the conditions have changed.

The credit predicted for the implementation of this program in 2016 is not sufficient anymore, and it should be doubled, he stated.

Considering the downward trend of the Caspian Sea level in 2021 which has increased almost 3 times compared to 2020, amounting to 12 cm drop, does dredging guarantee that the Caspian Sea water will be transferred to Gorgan Bay?

Therefore, it seems that dredging does not make sense, and assessment is required, he further noted.

According to forecasts, by the end of the current century, the water level of the Sea will decrease by 9 to 18 meters, making trafficking impossible through the Ashuradeh and Chap Oghli canals, while Golestan province will also lose access to Gaz and Turkmen port.

In addition to the impacts of climate change, global warming, and increased evaporation.

“Comprehensive management of this coastline should be in accordance with field evidence and engineering studies, for example, if dredging is to take place, new hydrography should be carried out on the Caspian Sea and Gorgan Bay to determine the difference in elevation.

Another issue is that we must have a safe canal at the best point, which is where the Caspian topography is at a suitable slope so that if the water level goes down, artificial canals and motor pumps drive water to the Bay,” he suggested.

Valuable ecological complex

Gorgan Bay was designated as a Ramsar site (defined by the Ramsar Convention for the conservation and sustainable use of wetlands, recognizing the fundamental ecological functions of wetlands and their economic, cultural, scientific, and recreational value) along with Miankaleh Wetland.

The bay and its surrounding area are recognized as a valuable ecological complex in the world which had a direct impact on the livelihood of local communities in addition to conserving the marine life cycle.

Ashuradeh Island, which hosts a variety of native and migratory birds throughout the year, was also introduced and registered as one of the world's first biosphere zones in 1975.

FB/MG