HomeMy WebLinkAbout10-07-2014 ph3 HitchnerRECE r-�.` --
Kremke, Kate I OCT ® 6 2014
From: Mejia, Anthony
Sent: Monday, October 06, 2014 8:04 AM
To: Kremke, Kate
Subject: Fwd: City Council Meeting October 7 -- on Chapter 9 of LUE and the impact of home
grey water recycling on long -term water supply
Agenda correspondence 10/07/14 PH 3. AGENDA
CORRESPONDENCE
Begin forwarded message:
Date "'-7 Item# PH-3
From: Bob Hitchner <bob(?nexusewater.com>
Date: October 5, 2014 at 10:46:16 PM PDT
To: <jashbaug_gslocity.org >, <dcaMentgslocit y�org >, <christi@slocity.org >,
<mcodrongslocity.org >, <cdietrick a slocity.org >, <klichtig_(kslocity.or >,
<jmarxgslocity.org >, <ksmith(a,slocity.org >, <amejia(a,slocity.org>
Cc: Andrew Christie <sierraclub8ggmail.com>
Subject: City Council Meeting October 7 -- on Chapter 9 of LUE and the impact of home
grey water recycling on long -term water supply
To: San Luis Obispo City Council
Re: Agenda, October 7 Council Meeting: Chapter 9 of the LUE -- Sustainability measures to
protect long -term water availability
Dear Members of the City Council:
I am writing with respect to the impact of the LUCE plan on water supply availability to support
growth and protect quality of life.
Chapter 9 currently calls for :
Quote:
9.3.7 Sustainable Design
D. Sustainable Design
Utilize plumbing fixtures that conserve or reuse water such as low flow faucets or grey water
systems, and encourage new Homes to be constructed to be arey water read )7. --
Unquote
I would like to help you quantify the possible value of residential grey water recycling, as called
for under the plan, with the hope that you will do more than simply "encourage" its use in the
years ahead.
On -site home water recycling can significantly cut the use of water in homes. Grey water is
actually an abundant resource found in every home, accounting for about 2 out of every 3 gallons
of water used inside the home. By recycling it, therefore, you can cut indoor consumption of city
water by that same amount, 2 /3rds.
Under the Plan, the population of San Luis Obispo is projected to grow by over 13,000 residents
over the coming twenty years, to 58,625. This is a population growth of 29 %.
4,900 new homes will be built to house the new residents. This increases the number of
households from 20,697 to 25,601.
The Water Supply Assessment (Appendix I) shows that San Luis Obispo can supply water to
these residents, but the extra water margin to protect against long -term drought is significantly
reduced.
Water Supply is estimated at 10,471 acre feet per year, with 5,541 acre feet used currently. This
means that San Luis Obispo currently has a "drought margin" of 47% excess water.
Under the Plan, without recycling, water use grows to 7,821 acre feet to accommodate the new
population. At that point, the "drought margin" of excess water will drop from 47% to just
25 %.
If all new homes were to be built the a robust "recycle- ready" standard, then any of them could
begin recycling water on site at any future date.
If every new home were converted to on -site recycling, how big would the impact be on San
Luis Obispo's water requirements?
In this case, water demand would increase at a much slower rate, and the city would have more
"drought margin" to protect itself against drought in the future. Instead of needing 7,821 acre
feet annually, the city would need 7,321 acre feet -- a saving of 500 acre feet, which cuts the
growth over the twenty years by 22 %.
The "drought margin" will grow by five full percentage points, from 25% to 30 %.
Obviously, on -site home water recycling in new construction is not the only measure that San
Luis Obispo should take to protect its long -term water supply. However, it is probably the most
cost - effective measure, and it is best taken at the time of initial home construction.
For this reason, I hope that you will be clear in your support and encouragement for building new
homes with appropriate on -site grey water infrastructure.
Regards
Bob Hitchner
PS -- "Home Water Recycling" and "On -site grey water reuse" are two different but similar
approached to reusing grey water on site. The first one actually treats the water before
reuse. The second one uses untreated water, with certain restrictions. Both are effective at
cutting water demand by homes.
Bob Hitchner
Chief Sales & Marketing Officer
Nexus eWater, Inc.
www.nexusewater.com
Mob 805- 444 -3275
Imagine H2O International Water Prize - 2012 Runner -Up
LAUNCH Beyond Waste Challenge - 2012 Semi - Finalist
US Cleantech Open - 2012 Semi - Finalist
SXSW Startup Showcase - 2012 Semi - Finalist
SXSW Eco i2i Awards - 2012 Finalist
Member - US Green Building Council