Need help in harvesting rainwater

Our apartment complex in Bengaluru has sloping roof which does not allow us to have a roof top collection of rainwater. All that water comes down and flows on the roads of the complex to the lowest point in our complex before it goes out. Can this water which has traversed the complex on ground level be used to recharge the borewell directly using just layers of differently sized gravel and sand or more sophisticated filtering will be required to remove cleaning chemicals and fertilisers (used in gardens) before it can recharge the borewell ?

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