Here in southern California ...

Here in southern California stormwater and streamflow has been used extensively to recharge our aquifers for many years.  Generally this water has a moderate TDS (1000 or so mg/l) and may contain sediment and manmade chemicals.  The undesirable elements such as oils usually pass in the first part of storm water so delay the first flush so to speak.  Initial sediment can be avoided mostly by delaying diversion to  the spreading basins.  After time the bottom of the spreading basins begins to seal because of sediment deposition and biological clogging of soil pores.  To combat this construct spreading basins so that they have a high ratio of side slopes where most of the percolation takes place.  Such basins should be on a regular maintenance program.  You might consult my book "Unsaturated Zone Hydrology" Prentice-Hall 1994 as well as some of my papers.