Problem with water from cold tank


New Member
I live in a house in eden gate delgany. All the houses have pumps in their cold water tank
I've got a problem whereby brownish colour water appears in sinks and wash hand basins/ toilets when you run the cold tap.
You have to run the cold tap for a while until the brownish colour goes away.

Someone said to me the pump in the cold water tank disturbs any dirt or sediment at the bottom of the tank and thats what this browish colour is.

But this has been going on for a while like a couple of months and surely any sediment in the bottom of the tank should be gone by now.
So does anyone else have the same problem??
I asked the builder and he just made out it was dirty water in the water mains which I don't believe.