Houston Sanitary Sewer problems

Does anyone know how to get permission to dispose of waste water in Conroe, Tx (close to Houston)? I've contacted the local and city sewers and they basically have no idea what I'm talking about. If I get a permit from the state to be a waste hauler do those sanitary sewers have to accept me? They aren't very eager or interested in helping a pressure washer owner of disposing of 500 gallons every few days. Any suggestions on how to proceed?

What is to stop you from using the sanitary sewer on site to discharge your water?
Around here, a sanitary sewer discharge permit is for a fixed location, and each business has one. Since you are disharging water their water, then you should not have a problem, unless you have some real nasty stuff.
I had a waste haulers permit, issued from the city, and it required me to discharge at the treatment plant, so they could test it first. I now discharge on site.


Also, who is to stop you from discharging in your home sanitary sewer?

Many cities have no clue how to deal with us. They may say that you need mnay expensive permits that you do not truly need, or they may say you need nothing.

What kind of wash water is this, and do you filter it, or just collect it?