A message from Vinay at Karmayogtells us that:
You can fill in details of rain-affected areas at the online SATYA form, which will help the authorities to take specific action. You can also upload pictures.
Your message will also be displayed on the Satya page at Karmayog.
You can also give direct feedback to the relevant person at Karmayog's BMC contact details page.
There are also monsoon tips and contacts available.