[8588] in North American Network Operators' Group
Re[2]: a generic water encapsulation technique [Re: floods]
daemon@ATHENA.MIT.EDU (pkavi@pcmail.casc.com)
Fri Apr 11 09:28:55 1997
From: pkavi@pcmail.casc.com
Date: Fri, 11 Apr 97 09:17:18 EST
To: kwe@6SigmaNets.com, peter@tdi.net
Cc: nanog@merit.edu, Hoisl@aol.com
Peter,
What you said is true if the drain system treats all fluids equally. But
consider the difference between these fluids.
It is much more important that sewage water, with its Constant Flow Rate, get to
its intended destination and not leech its pollutants into the ground. Storm
water, with a bursty Variable Flow Rate, will not cause environmental damage if
leeched into the ground during overflow cases. What is needed is a drain system
which can distinguish between storm water and sewage.
Prabhu
______________________________ Reply Separator _________________________________
Subject: Re: a generic water encapsulation technique [Re: floods]
Author: peter@tdi.net at SMTPLINK
Date: 4/10/97 10:56 PM
Kent W. England wrote:
>
> We could also multiplex the rain water with the sewage water in a
> multi-mode drain system. Internet drain specialists tend to take religious
> points of view on whether we should have separate drain systems, should
> combine them, or outlaw one in favor of the other. But, clearly,
> encapsulation is the favored approach.
>
The multiplexed drain system will never work. Sewage water we know
to be a fairly constant flow over time, and in fact sanitary engineers
refer to it as having a Constant Flow Rate. Storm water, on the other
hand, is
very bursty in nature, and sanitary engineers describe that as Variable
Flow Rate. In the old days they tried combining drain systems, sharing
the resources between the CFR water and the VFR water, and called the
result AFR (or
available flow rate). AFR had one weakness, however: it relied upon a
phenomena called precipitation shaping to keep the VFR storm water from
interfering with the CFR sewage water. As the clouds and the ground
didn't
have enough buffering to do proper precipitation shaping, the result was
a drain system which periodically suffered massive congestion, and all
users were equally unhappy.
-peter
