Around the rocky's - I've noticed that storm drain systems are always a huge piece of infrastructure. They seem to dump to the local river. Why don't the citi

Around the rocky's - I've noticed that storm drain systems are always a huge piece of infrastructure. They seem to dump to the local river. Why don't the cities harvest that water and treat it instead of dumping it into the river? They may be able to build retention ponds and hold on to it for a while. Treat it later. No need to just toss it.