The Public Works Department (PWD) has started preliminary work on redeveloping the drainage system in a bid to resolve waterlogging woes that plague the capital every monsoon — beginning with the Najafgarh basin, which covers 123 drains.
It has also floated tenders for engaging a consultant to conduct a survey and come up with a Detailed Project Report (DPR) for redeveloping and re-constructing the drainage system. After finding the ‘Drainage Master Plan’ prepared by IIT-Delhi generic in nature, the Delhi government had last year appointed PWD as the nodal agency for the project.
A senior PWD official said: “Waterlogging and urban flooding are a perennial problem in the capital. The main reasons behind this are the city’s topography, which restricts the gravity flow of stormwater; mixed flow in stormwater drains; intense rainfall much higher than designed capacity of stormwater drains; disposal of silt and construction waste; and ineffective desilting.”
To address these problems, the government has decided to find drainage solutions for each of the three basins in Delhi at Najafgarh, covering an area of approximately 980 sq km, Barapullah, and Trans-Yamuna.
“We are kicking off work from the Najafgarh drain basin. The tender process to appoint a consultant has begun; they will study the entire basin area and the drains covered under it. The objective of the consultancy service is to provide solutions as per the framework of the drainage master plan and a system where no waterlogging occurs in the NCT of Delhi-Najafgarh Basin,” said the official.
Tenders for appointing consultants for the two other basins will also be floated.
The official added: “The consultant will further provide solutions for individual drainage at the macro level and specific locations. Reasons for waterlogging, delay in drain of surface runoff, constraints and solutions, rainfall distribution, reuse of stormwater etc., will be covered in the feasibility report.”
Besides, a hydraulic study to test soil and water, and a topographical survey of existing pipelines, drains, and other possible stormwater disposal systems at all probable waterlogging locations will be conducted.
Once the consultants are engaged, the DPR will be ready in 9 months and solutions will be implemented by the respective road, drain-owning agencies — PWD, MCD, DSIIDC, DDA, DJB and other departments concerned.
The city’s entire drainage system will be redeveloped by 2025 under the master plan, said the official.
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