Heavy rains lashed the city on Sunday, causing flooding in many parts of Bengaluru.
Incidentally, a report released by the Comptroller and Auditor General (CAG) of India in the last week of September indicated that this could happen. The report highlighted the issue of encroachment of lakes in the city and the failure of the Bruhat Bengaluru Mahanagara Palike (BBMP) to connect drains with storm water drains (SWD).
The CAG report titled ‘Performance audit of storm water management in Bengaluru urban area’ revealed that shrinkage of water bodies and drains has resulted in loss of connectivity between water bodies and drains.
According to the report, out of 2,626 encroachments identified near water bodies in various areas, the BBMP was yet to remove 714 encroachments. Audit noticed 23 cases of significant violations, out of which 16 cases were not in the list provided by BBMP. The CAG also observed that the report provided by BBMP Chief Engineer of Lakes Division was not reliable as joint inspection revealed that one of the removed encroachments existed and the removals carried out were also incomplete.
Joint inspection of drains revealed that SWDs were not directly connected to water bodies, lakes in some cases and runoff was flowing into created diversion canals. It has been said in the report that due to this the possibility of flash floods has increased.
“The flow paths/beds of the drains were paved. This not only affected the hydrological functional potential of the SWD but also affected the groundwater recharge. Besides, the concretization of SWD has also increased the chances of being vulnerable to repeated floods,” the report said.
The CAG also highlighted the issue of conversion and concretization of water bodies. For example, Kamakshipalya lake has been converted into a sports ground and Dasharahalli tank has been converted into Dr BR Ambedkar Stadium.
As per the data shared with the CAG by the Chief Engineer of the Lakes Division of BBMP, out of 210 lakes/water bodies in Bengaluru, 66 are yet to be developed, 18 unused and 37 lakes are in the process of being rejuvenated. The 18 lakes that were reported to be unusable are spread over a total area of 254 acres. There is a significant potential for these lakes to be encroached upon and converted for other uses in the future.
The report also noted that the failure of the BBMP to ensure the connectivity of drains with water bodies has facilitated the drying up of several lakes in Bengaluru city, leading to conversion of lakes for other purposes.
According to the CAG, SWD works with an estimated cost of Rs 61.21 crore were taken up especially for sewage diversion and to improve the environmental conditions near water bodies. Joint inspection revealed that sewage was always flowing in all sections of the drains and was being discharged directly into the lakes. This made expenditure largely unproductive.
Highlights of the CAG Report
- Encroachment of lakes and SWDs has resulted in a decline in the groundwater table, while increasing the risk of flooding.
- Dumping of solid waste, construction debris etc. in SWD, lake catchment area and lakes.
- The continuous flow of sewage, partially or untreated, pollutes existing surface and subsurface water resources.
- Due to accumulation of silt and debris, the water holding capacity decreases.
- Loss of interaction between water bodies.
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