News Release - Save Los Osos Water

News Release
For Immediate Release
November 7, 2014
Los Osos, California
New report shows accelerated rate of seawater intrusion in Los Osos
Groundwater Basin
Los Osos water purveyors urge conservation of critical water supply
President
Craig V. Baltimore
Vice President
R. Michael Wright
Directors
Leonard A. Moothart
Marshall E. Ochylski
Jon-Erik G. Storm
General Manager
Kathy A. Kivley
District Accountant
Michael L. Doyel
Fire Chief
Robert Lewin
Battalion Chief
Phill Veneris
Mailing Address:
P.O. Box 6064
Los Osos, CA 93412
Offices:
2122 9th Street, Suite 102
Los Osos, CA 93402
Phone: 805/528-9370
FAX: 805/528-9377
Los Osos, CA – A newly released study has documented a significant increase
in the rate of seawater intrusion in the Los Osos Groundwater Basin, worsening
an already critical water supply situation. The new study was prepared for a
technical working group comprised of representatives from the three water
purveyors in Los Osos and San Luis Obispo County. The Los Osos water
purveyors are urging residents to continue efforts to conserve water in an effort
to improve the situation.
The study, conducted by Cleath Harris Geologists in July and August of this
year, details the seawater intrusion rate within several of the basin’s aquifers,
with the most notable change in a zone that serves as a principal water supply
for the community (see Figure 1).
In the critical water supply aquifer known as Zone D, intrusion increased from
an average rate of 60 feet per year from 1985 to 2005, to a current rate of
approximately 200-250 feet per year. Geologists expect the front could reach
an important water supply well known as the Palisades well (see Figure 2)
within the next five years if the basin situation does not improve.
The study underlines the three purveyor’s ongoing efforts to implore water
users to cut back, as increased seawater intrusion is directly related to declining
fresh water levels in the basin. Although groundwater pumping has declined
since 2009, that progress is offset by the ongoing drought and lack of
freshwater recharge to the basin, and additional conservation is critical.
The Los Osos Community Services District recently launched a new public
awareness campaign to encourage increased conservation, called “Together
We Can Bear It: Save Los Osos Water.” The campaign points residents to
LosOsosCSD.org, where they can learn more about free water conservation
tools, as well as landscaping tips and conservation rebates available to them.
In September, the Los Osos CSD Board of Directors implemented the Water
Shortage Contingency Plan Phase II, which places restrictions on outdoor
water usage for residents and construction.
On November 13, the board will receive the official seawater intrusion report
and will discuss the need to expedite both conservation and other physical
solutions listed in the basin plan.
To see the plan summary, visit http://www.losososcsd.org/cm/Home.html
Contact: Kathy Kivley
General Manager, Los Osos CSD
kkivley@losososcsd.org
www.locsd.org
###
B
West
Rosina Well
Pecho Well
Sea Pines Well
200
B’
East
Palisades Well
Los Osos Creek
Dune sand
100
Zone A
0
Zone C
Moved 2,000 feet
from 2005 to 2014
-200
-300
-400
-500
-600
1000
y
Cla
y top
la
AT3 C
Moved 1,200 feet
from 1985 to 2005
le
Zone E
f
eo
b
ea
se
ts
en
dim
rm
pe
s
Ba
Moved 4,600 feet
from 1977 to 2004
Sandstone
stone
Sandstone/mud
(projected)
0
AT3
Zone D
-700
-800
lay
C
AT2
AT2 Clay top
Fault-bounded basin boundary
Elevation in feet above sea level
Sea Level
1985-2005
transition
zone
?
-100
Zone B
Sand spit
Pacific Ocean
2000
3000
4000
5000
6000
Siltstone
7000
Base of permeable sediments
8000
9000
10000
11000
12000
Moved 1,500 feet
from 1977 to 2005
13000
14000
Moved 1,000 feet
from 2005 to 2014
15000
16000
17000
18000
19000
20000
21000
22000
23000
24000
25000
26000
27000
28000
Horizontal distance in feet
Estimated extent of intrusion
NOTE: the transition zone lines are interpreted from
available water quality and geophysical data, and include
consideration of well construction and use. Intrusion
rates are estimates based on interpreted advance
of toe of transition zone. Rates within zones can vary
based on preferential pathways. The generalized slopes of
the transition zones were based on geophysical logs and
water quality obtained during the 2005 study and have
been maintained for consistency.
Aquifer Zones:
Zone A - Perched Aquifer
Zone B - Transitional Aquifer
Zone C - Upper Aquifer
Zone D - Lower Aquifer (shallow)
Zone E - Lower Aquifer (deep)
1977 (Zone E)
1985 (Zone D)
2005
2010
2014
Inferred location of seawater fresh water transition zones
1977 (Zone E)
1985 (Zone D)
2005
2010
2014
Figure 1
Lower Aquifer
Seawater Intrusion - 2014 Update
Los Osos Valley Groundwater Basin
Los Osos ISJ
Cleath-Harris Geologists
hS
10t
t
tree
Intrusion in
Zone D in 2009
ven
tion
Cross-sec
re 1)
line (Figu
der
alley Road
Los Osos V
Bro
Intrusion in
Zone D in 2005
A
son
Intrusion in
Zone D in 1985
ue
Intrusion in
Zone D in 2014
Figure 2
Zone D Intrusion Front
Seawater Intrusion
2014 Update
Explanation
Well location
approx. basin limits
Scale: 1” = 2000’
Base Map: USGS Topographic Map
Morro Bay South, 1994
0
2000