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Re: degrease

To: Harry Trafford <traff@icon.hmsd.ufl.edu>
Subject: Re: degrease
From: pethier <pethier@isd.net>
Date: Wed, 04 Feb 1998 12:53:02 -0500
Harry Trafford wrote:
> 
> Most, if not all self-service car washes in the States recycle and filter 
> all that water that goes down the drain, where it is stored in huge holding 
>tanks. 

News to me.  Do you have a source for this information?

>It's the law. 

Whose law?  Federal?  State?  Local?

I have been the sewer-charge administrator in Saint Paul, Minnesota for
eight years.  I have never come across any such law.  All the car washes
of which I am aware dump their water straight into the sanitary sewer,
which leads to the Twin Cities' metro sewage-treatment plant at Pig's
Eye (yes, named after the same person as the beer).

If a car-wash operator wants to recycle and filter all the water, we
won't stop him.  But paying the water and sewer charges has to be
cheaper than huge tanks and an endless parade of filters.  I don't know
how the operator would economically get the dissolved salt out of the
wash water in the winter.  I don't think he'd stay in business long if
his customers found out they had been spraying salt-water on their cars
all winter.  If an operator did recycle, he would have to figure out
what to do with all the sand and garbage from his filters.  Eventually,
he'd have to dump a lot of water into the sewer anyway, because there
would be no place to put it.  Considering that water costs $1.31 per CCF
and sewer charge is $2.42 per CCF (1 CCF = 100 cubic feet = 748
gallons), I doubt that recycling could be done more cheaply than letting
Metropolitan Council Environmental Services clean it up and dump it in
the Mississippi.

Now maybe in Los Angeles or some other place where water is hard to come
by and therefore more expensive, this may make sense.

Phil Ethier

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