I'm sure things are more strict in CA, but in CT my understanding of the regulations is that as long as the water isn't hitting the storm drains- I'm clear. This allows me to bypass reclamation when waste water is either evaporating or entering the ground. Additionally, parking garages are required by law to have an oil/water separator- so I'm covered there with property owner approval. In drainage sensitive areas I use a either ONR or a combination of sand barriers and a vacuberm- and I'm working on a self contained pump/tank setup. My reclaim is approx 40-60% of the water used depending on weather conditions.
I consider myself a fairly eco-conscious individual and I agree that car washing should be among the least of our government's concerns in terms of pollutants. If your using biodegradable and phosphate free chemicals, and not degreasing an engine you should be able to claim exemption.
"The most common method of compliance with the CWA is to prevent process wastewater discharges to waters of the United States. If your discharge does not reach waters of the United States, then there are no requirements under the CWA. Examples of compliance without a discharge are vacuuming up the process wastewater or berming the process water and allowing it to evaporate. An additional method of compliance is to discharge the water to an NPDES permitted sanitary sewer system (the municipality may have additional pretreatment requirements before accepting your discharge). The most common form of non-compliance is to discharge the process water into a storm sewer system or into a city street that drains to a storm water inlet. Most storm drainage systems discharge directly to waters of the United States without treatment, which means anything that discharges into a storm drain is the same as putting it directly into the waterbody receiving the storm drain discharge."
