Being separated from the seashore by 7 km should be a reasonable safeguard against frequent tidal flooding.
But for nearly 300 families of the low-lying Thuruthipuram-Vellottupuram area spread over three wards of Puthenvelikkara panchayat in Ernakulam district, one of the worst affected in the 2018-deluge, tidal flooding has become a monthly affair for four days following every full moon day.
Now, a community-driven tidal flooding mitigation programme is under way in the area under the joint aegis of Equinoct—a community-sourced modelling solution provider initiated by IIT Bombay and NIT-Calicut alumnus—and Community Resource Centre (CRC), Puthenvelikkara, with the support of the civil engineering department of SNM College, Maliankara.
“The project has been running for around six months now and during the period we have noticed an average tidal flooding of 10 cm to 30 cm, and it could well go beyond that during December. We are still in the first stage of the programme, where the emphasis is on data-gathering based on which we will do a contour mapping, identify the most vulnerable areas, and do a detailed study of streams contributing to flooding in the successive stages,” said C.G. Madhusoodhanan, CEO, Equinoct.
A proposal by the panchayat for undertaking a study on tidal flooding prior to getting into any mitigation work is now under the consideration of the District Planning Committee (DPC). This perhaps is the first time that a panchayat is going forward with scientific assessment of the situation before sanctioning any physical work, he added.
CRC has installed 17 tidal gauges in the area and has trained community members in gauging tidal flooding. “We have a WhatsApp group, where they will either post each gauge reading in real time or a consolidated report. We have codenamed each gauge from TG01 to TG17 and record the reading from each gauge separately during every 15 minutes during flooding,” said P.N. Maya, coordinator, CRC. Steps are under way to record them on a web-based platform.
The installation of gauges, measurement, and data upload into the platform have become a community education exercise, especially for children and women.
Gauging is done three hours before and after the maximum tidal flooding as forecast by the tidal gauge on Willingdon Island in Kochi. Though the area falls within the high tide line marked as part of the Coastal Regulation Zone mapping, water level has now gone beyond that mark.
“Tidal flooding has a detrimental effect on life and property in the area with frequent saline water intrusion inflicting structural damage to houses, a desertisation-like impact affecting agriculture, and drinking water shortage,” said Mr. Madhusoodhanan.
