HomeMy WebLinkAbout12-15-2015 Item 14 ShanbromCOUNCIL MEETING:
ITEM NO.:
To: Maier, John Paul
Subject: RE: AC - FW: Water /climate projections
DEC 14 2015
From: j
Sent: Monday, December 14, 2015 7:36 AM
To: Floyd, Aaron; Carpenter, Dan; Carpenter, Dan; Rivoire, Dan; Ashbaugh, John; Marx, Jan; Christianson, Carlyn; Maier,
John Paul; Goodwin, Heather; Lichtig, Katie
Cc: Mattingly, Carrie
Subject: Re: Water /climate projections
Hi Aaron,
PLEASE INCLUDE IN CORRESPONDENCE REGARDING THE APPROPRIATE AGENDA ITEM FOR THE COMING
MEETING, DEC. 15.
cc: Mayor, Council, Clerk, CM, Carrie Mattingly
I don't feel I'm getting my questions answered adequately....
At what points does Lake Nacimiento go to operational minimum pool (go dry)? There are many scenarios for this
question as drought is a product of lack of rainfall over time, so I have posed some specifics again below for your
consideration....
a) Would Lake Nacimiento go dry if our current drought (60% of normal rainfall over four seasons) lasted one more year?
two more years? three more years? What would the city do if Lake Nacimiento went dry? Please let me know in acre -feet
per year by source, i.e, emergency groundwater, recycled, re -used, desal, etc.
b) Some climate models predict that San Diego's climate will migrate to SF over the next century. That would mean that
our watershed would receive about 50% of current rainfall. Would Lake Nacimiento go dry at some point during that
scenario? Again, what would the city do? Please let me know in acre -feet per year by source, i.e,
emergency groundwater, recycled, re -used, desal, etc.
c) How much water would be in Lake Nacimiento right now if the County were to allot the 6100 of /year up for grabs (of
which the city is requesting one - third, 2100 of /year)? How much sooner would Lake Nacimiento go
d) How does adding approximately 20% to our city's population by 2035 make us more water secure, if at all?
e) Do you anticipate a shortfall in sewer revenue in the coming year? How would such a shortfall be covered? By
another rate hike (surcharge) or by some other means? Would adding 20% to our population tend to trigger earlier rate
hikes (surcharges)?
Thank you.
Bob Shanbrom
364 Montrose Drive
- - - -- Original Message---- -
From: Floyd, Aaron <afloyd@slocity.org>
To: shanbrom <
Cc: Mattingly, Carrie <cmattingy @slocity.orq>
Sent: Thu, Dec 10, 2015 6:37 pm
Subject: RE: Water /climate projections
Hi Bob,
Thanks for the wait while I found a moment to respond to your questions.
Here's a piece of information and web link from the Monterey County Water resource Agency
www.mcwra.co.monterev.ca.us/ reservoirs - dams /reservoirs -dams overview.Dhc
The physical minimum pool or dead pool is at an elevation of 670 feet, 10,300 acre feet of storage. The operational minimum pool is at
elevation 687.8 feet, 22,300 acre feet of storage. Water below an elevation of 687.8 feet is reserved for fish and wildlife habitat as well
as a water entitlement belonging to the County of San Luis Obispo.
This highlighted section addresses the contractual water rights the City has with its partners in Nacimiento. By
contract, we receive the first water in and the last water to come out of the reservoir.
Attached is a diagram that shows historical lake levels at Nacimiento including the operational minimum
pool. Up until the early 1990's a required release of around 100,000 acre feet annually was also in
effect. That can be seen by the lower storage levels throughout the 1980's. This is no longer the situation, so
the reservoir levels stay higher. It's also important to remember that at the operational minimum (red line), we
still have our full entitlement, including the proposed additional 2100 acre feet.
Beyond this immediate situation, the point you raise regarding where we will be in the future is an important
question. The lens through which I look at water supply issues is in the 50 to 100 years out timeframe. I'm
pleased to say that the City of San Luis Obispo is well positioned to meet our future needs. Unlike many
communities that receive water from a single source, the City utilizes three surface water reservoirs. This helps
if maintenance or repairs needs arise. The City also has groundwater available to assist with meeting potable
water needs. Additionally, we also have a recycled water system that offsets potable water use.
The City is also preparing for the quickly approaching upgrade to the Water Resource Recovery Facility
(wastewater treatment facility). With this upgrade, we will have a system in place in which we will be able to
quickly adapt our process to allow highly treated wastewater to be injected back into the groundwater basin
and pumped out after a length of time - or directly used for drinking water. This will require regulations to be
adopted at the State level, a reality that will likely be coming within the next five years.
Lastly, our conservation program and the work of the community to save water is strong. This extends beyond
just taking shorter showers and includes new water conserving plumbing standards and landscape
requirements. Saving water equals creating water and these efforts will further help us meet our needs into the
future.
With all of that said, I am enjoying today's rain, looking forward to Sunday's continued storm
forecast, watching the El Nino predictions, and looking forward to the day when this current drought will be
over.
Thanks again, Bob.
Aaron
From:
Sent: Tuesday, December 08, 2015 11:41 AM
To: Floyd, Aaron
Subject: Fwd: Water /climate projections
Hi Aaron,
Here is my recent email to Carrie. These are the same questions I posed in Sept when Carrie, Ron Munds and you and I
met. I would like to know what the minimum pool is for Nacimiento. If the current drought were to continue one more year
or two more years or three more years what are your projections for Lake Nacimento a) at current allotment b) at
proposed allotment? Currently Lake Nacimiento is at 18 %, just four seasons after overtopping. If we had been receiving
an additional 2100 of then it would be at about 14 -15 %. Doesn't this seem like a 5 or 6 year drought like our current 4
year drought would empty LN?
Bob
- - - -- Original Message---- -
From: Mattingly, Carrie <cmattingly@slocity .or g>
To: shanbrom <
Cc: Floyd, Aaron <afloyd(@s1ocity.org>
Sent: Fri, Dec 4, 2015 4:51 pm
Subject: RE: Water /climate projections
Dear Mr. Shanbrom,
Good to hear from you. And thank you for the kind words.
I've forwarded this email (and your email from today) to our water division manager Aaron Floyd. Aaron has
been out of the office the last two days. I'm sure he'll get in touch with you early next week.
Sincerely,
Carrie Mattingly
From:
Sent: Thursday, December 03, 2015 7:28 AM
To: Mattingly, Carrie; Mattingly, Carrie; Carpenter, Dan; Carpenter, Dan; Rivoire, Dan; Marx, Jan; Christianson, Carlyn;
Ashbaugh,John
Subject: Water /climate projections
Dear Carrie,
Mayor, Council- -could you please respond with an acknowledgement so that I know you have
received my email. Thank you.
Do you have the water supply /climate projections ready for my viewing? Specifically, I would like to see the figures that
relate water supply to a "new normal" rainfall for the watershed of 20 inches (normalized to SLOtown) /17.5 inches /15
inches/ 12.5 inches. Or, 90 %, 80 %, 70 %, 60 %, 50% of normal for the watershed. Do you have price projections and
household allotments that correspond to these conditions?
At some projection point I think that our only unassailable supply becomes Lake Nacimiento. Beyond another projection
point even LN becomes questionable. If LN were our only source then I'm estimating that the average residential use
would need to be in the neighborhood of 50 -60 gallons /person /day at buildout plus projected annexations (all hookups
completed and growth capped). Does this figure seem reasonable to you?
Thank you for your hard work on this critical issue.
Bob Shanbrom