Construction work for mountainous erosion control at Alenze Sub-Basin of Masal River Basin (JPA-2017) was completed by the Watershed Management Sub-committee of the Anzali Wetland Management Committee in September 2017 as a Joint Pilot Activity under the project. An inspection was carried out in the middle of May 2018. It was confirmed in the inspection that all the constructed structures kept good condition after the most severe season from autumn to spring with heavy rain and snow.
After the spring season, normally no heavy rain is observed at the area. However, one big rain occurred in the area in beginning of June this year. It was abnormal weather event in the area.
Mr. Asadi, NRWGO Gilan, a main counterpart of the Watershed Management Sub-Committee, visited the site to check the condition of the construction area on 14 June 2018.
It was confirmed that all the constructed structures functioned as designed. The wall-structures stopped the sediment flow and reduce their energy, the water channels limit the water and sediment flows to prevent any damages on the both sides of the channel, and the ford crossing structure protected the road completely and no damage was seen on the road.
Can you image? If there were no structures there, the flash flood flowed quickly with high energy. It eroded the soil block, which located just upper side of the road, and eroded soil would be mixed with the flowing sediment and increase the energy much more than initial one. Then, the sediment flow attacked to the road directly, as result, destroyed the road completely.
However, current situation shows all constructed structures stopped such water and soil moving correctly. As result, no damages occurred on the road and the stream area as well.
Someone may say there are large holes on the water channels. Yes, there are. However, the purpose of the structures is “to prevent disaster influence and minimize the damages on the property and nature at the site”. Beautiful structures mean not working, getting dirty or damaged structures shall be evaluated as “functioned” by absorbing the energy of nature.
NRWGO Gilan is under preparation of the construction this year, which is on the track. The construction will be carried out at upper and downstream of the existing structures, which was constructed under the JPA-2017. The continuing construction until perfect formation of structures shall function much, and it is highly expected NRWGO Gilan would complete the works there.