Hi, installation is on a business park and they wish to have a bucket sink installed in an area where there is no foul water drainage. They have 4 inch rain water pipes near by and am not sure of the regs whether I can use the rainwater point for just a sink or weather they are shared drainage, please help.

Sink water is considered gray water and should not be run to storm run off. It must be run to a septic tank or sewer.
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