How to reach to net-0 water building

In my last blogger, I mentioned that algae cell may use brown water as its nutrition solution. That makes me think that whether we can reach to Net-0 water building through this processing which is another factor of reach green building. ( for example, LBC (Live Building Challenge) evaluation requires green building to be Net-0 building) 

In Florida, annually rainfall is about 50-60 inches. Most of the water goes into or under ground. Storm water are not portable in any culture, but they are not "dirty". We may use it for toilets and urinals flushing, irrigation or the fire sprinkler system so that valuable portable water can be saved. However, that's not enough to reach "Net-0" water building. We may want to go deeper on how to use these storm water. ( the amount of storm water is not a factor to be worried about in Florida but some other "water shortage” states such as Nevada.) 

If storm water is the only water resource other than tap water, and we have plenty of them, The first thing to do is to make it portable. A technology called membrane bio-reactor (MBR) can help reach the function. 

After purifying processing, we will have totally portable water. Next step will be how to treat the waste water. (because gray water and black water are too dirty to treat by MBR) We should at least transfer the gray or black water into the same cleanliness as storm water so that it won't pollute the nature (also can be recycled if necessary). We may use "Living Machine" to reach that goal: use soil and plants (algae mentioned before is also counted as plants) as first purifier:

As the a system, it should look like so:

   It is only a concept of how to achieve Net-0 water building in Florida. Further research and feasible reports will be needed.