Scenario – Basement flooding
One of the facilities in our portfolio had the utilities including electrical switch gear and back up gensets located in the basement. A mission critical, shared data centre was located in another floor of this facility.
Early morning, on 25th Oct 2005, it rained about 21 Cms within a six-hour period – unheard of in Chennai, India and not an emergency really planned for; considering the low probability of occurrence.
Water was flooding the basement through the WCs and urinals located below ground level. Luckily the Emergency Response Team responses were timely and communications were good. All the available portable pumps were put into use and people from all the groups worked as a team. Additional manpower was brought for assisting the site team, from other premises.
The utility supply had to be switched off when the water level rose to about 8 inches in the basement, but the gensets took over the supply. The connected critical data center continued to function without any interruption throughout the deluge.
Root Cause. During one of the modification done by the building owners, the sewage system made of 8 inch pipes were connected erroneously with the storm water drains leading to the rainwater harvesting well. The pipes were too small for the kind of flow experienced during the heavy rain and caused reverse flow into the basement through the WCs and urinals.
Once the problem was isolated, the pipes leading to the below ground level restrooms were blocked temporarily using small sand bags, cotton waste and cloth. They were permanently closed afterwards and the room was converted into a storage space for spares and consumables
A well-trained and motivated ERT, ready availability of portable pumps on site and common sense saved the day in the above event.
Part 3 will follow shortly.