Poor drains that are overwhekmed in heavy rain flooding my garage

There are 2 drain entries at the bottom of the cul de sac which covers St Agnes Road nos 25 to 35. The road slopes to the. When it rains hard the drains fill and overflow sending water into the gardens and garages of numbers 30 down to 27. WSCC attended job number 902165 (WSCC-728960916). They stated initially: On inspection of the two gulleys at the end of the cul de sac closest to you property, both were clear of debris across the gulley grill, and both had water in, 60cm below the surface level indicating that water is draining away. Much of our drainage system was never constructed to handle some of the extreme weather events we have recently experienced which can often overwhelm a functioning drainage system. I am aware of the flooding you experienced both in your garage and across the front of your property. I will establish when the gulleys were last emptied and what the schedule for their next maintenance is. I will consult with our drainage team regarding the possibility of larger gulley grills as requested, but my experience is that no matter how large the gulley drill is, it will not mitigate flooding if the drainage system below the surface cannot cope with an extreme rain fall. A second email followed saying: no repair needed and the situation was not serious. I agree no repair needed but WSCC need to put in better drain or other mitigation to stop our properties flooding. There was also actions in the first response that require an update.