A new build I'm doing on my land in the countryside, I'm hoping to run surface water into my own brook as it's about 15 meters from the edge of the property and the soil is heavy clay. It's seems the most logical answer rather than an attenuation tank because when the rain pours down, in the wettest times of the year, the soil not being free draining and the amount of water coming down the brook (it's taking road run off) it can on the very odd occasion burst it bank and overflow into the field (hence why I'm raising up my new build) and usually takes a good 1/2 day to begin to drain away and to stop my field looking like a lake. An attenuation tank would just fill up from the brook overflowing. Unfortunately the architect has popped in an attenuation tank into the drawings which unfortunately I asked them to remove because of what happens but they didn't so Building Regs now have this tank in their drawings and I'm hoping they will see that it's not necessary. Any experiences/thoughts on this please?