I meant to post earlier, but was airborne traveling back the UK via another of the Gulf States.
Having spent many years working on water and sewage projects in this part of the world, the storms are extremely difficult to manage. The main problem is the lack of rainfall for 99% of the year but plenty of airborne sand and dust accumulating in the pipes & culverts. When the rain finally arrives - often in torrential downpours of more than 75mm/hour intensity - the accumulated sand & dirt are swept into the pumps. As you might image Storm pumps are robustly built but still unable to cope...