Islamabad: The Capital Development Authority (CDA) is all set to construct three wetlands to cleanse contaminated water before it meets the Rawal Dam, according to the news sources. The project is likely to take a few months for completion.
CDA has taken on the responsibility to supervise and finance the project, however, the Sanitation Directorate of Metropolitan Corporation Islamabad (MCI) will execute it.
These wetlands are to be constructed at Muslim Colony Bari Imam, Banigala and Bari Imam Shahan. Under the treatment of these wetlands, the contaminated water of the nullahs will be directed to specified sewerage treatment tanks for sedimentation. Afterwards, the tank water will again be released in the nullahs, from where it will flow through soil with some special plants to further purify the water, before it can become part of the dam water. A special plastic membrane has been laid out at the bottom of the tanks to control seepage of contaminated water.
The wetlands in Muslim Colony and Banigala are expected to be operational in a couple of weeks. However, the construction work on Shahan Bari Imam is stalled due to rain.
Please note that CDA allocated area for wetlands at an earlier date, in order to treat water coming in the Rawal Dam from the seasonal nullah.