Conclusion

Urban flooding has become an annual event in the Bangalore city although it is situated on a very high ground and slopes in all directions. Much of the flood marks leaves behind a lot of USW in its wake and it is often suspected that the presence of a large load of USW chokes the water flow under road bridges, especially in low lying areas and causes water levels to rise and inundate the houses nearby. Three key locations of flooding were studied in detail and commonalities of flooding were observed.  Firstly it is clear that being a low lying area and poor drainage caused by encroached drainages makes the location quite prone to flooding.  Second, a large load of USW disposed into this drain upstream aggravates the situation by partially choking the water course under these road bridges to cause a temporary flooding.  Third the presence of other pipes across the flow path provides barriers on which solid waste particles can adhere and allow the drainage path to be choked.