PILOT PROYECT
They chose Peach Blossom Pool Park as a pilot project. It is a popular urban riverside landscape park located in the lower reaches of Chanhe River, covering an area of 101 hectares, including 40 hectares of water
surface. The small lake inside the park was heavily polluted, and residents had made a lot of complaints about it.
PILOT PROJECT
The flood discharge from Chanhe River and the overflow of sewage from the upstream sewage treatment plant caused problems: the sediments in the lake were silted up, the water body was polluted, and the aquatic environment been seriously deteriorated. It was decided that the pulluted sludge was to be removed by environmental dreddging techniques. The goal was to speed up the flow rate of the river, improve the ecological conditions, and restore the aquatic environment.
CHOOSING THE BEST TECHNOLOGY
It is not easy to carry out dredging works in Peach Blossom Pool Park, which is in the center of a densely populated metropolis.
First, it is difficult for large-scale machinery to access the site, and to transport the dredged sludge outside the city. Second, the working conditions and engineering construction were complex. For example, the water surface was covered by aquatic vegetation. The water depth was generally less than 50 cm, and some areas were even free of water, so ordinary dredgers could not work there. Third, the execution standards were high. The dredging works had to be carried out without disturbing
the surrounding environment and nearby residents. Fourth, the planned construction period was short. The total dredging volume was about 15,000 cubic meters.
It was expected that the machine should complete the project within 25 days.
One of the project partners, Shaanxi
Chenghai Water Engineering Co., had fortunately just purchased the perfect technology for the project from Finland. They chose the original amphibious multipurpose environment dredger, Watermaster, because of its leading performance and operational reliability. Aquamec Ltd. has developed and manufactured Watermaster environment dredgers for more than 30
years. The dredger is small, lightweight,
and easy to transport. It is suitable for shallow water or even water-free operation.
The machine can access almost every site imaginable. During the operation, there is no need for auxiliary equipment, and one Watermaster can perform the work of a complete dredging fleet. With accurate
and environmentally friendly operation
and high efficiency, it is much better than the traditional way of dredging.
CHALLENGING CONDITIONS
Watermaster is based on an amphibious design. It could be put into operation immediately upon arriving at the new site.
Watermaster first began to renovate the
revetment, widen the river channel, and
remove the construction waste from the
bottom of the lake by excavating. Then,
Watermaster used the rake to clean up
the debris and vegetation near the water surface. In four and a half days, 40,000 square meters had been cleaned up. Then Watermaster proceeded to remove the sludge by cutter suction dredging.
One of the difficulties of the project was
the transportation and disposal of dredged sludge. The following plan was agreed on: cutter suction dredging by Watermaster + transportation by pipeline + dewatering by
geotextile tubes. This combination made it possible to meet the strict requirements of environment dredging and ensured high dewatering efficiency. All the dewatered sludge was used for landscape reconstruction.
The whole project was completed 5
days in advance.
POSITIVE RESULTS AND FEEDBACK
The results were very positive. The overall water flowrate in the East Lake of Peach Blossom Pool Park increased significantly, the water quality and the visual effect of the water surface improved, and the quality of air in the surrounding residential zones enhanced. The residents’ feedback
was appreciative, which had never
happened before in any engineering construction site of the city.
Since the completion of the project, the
contractor has got recognition from the
project owner and praise from local people.
It has become a model leading the
field of environment dredging in Xi’an
and the whole northwest area.