Docstoc

Coachella Canal is Drained for Repairs and Thorough Inspection

Document Sample
Coachella Canal is Drained for Repairs and Thorough Inspection Powered By Docstoc
					Volume 8, Number 7                             Coachella Valley Water District                                     August 2004

Salvinia is a Giant
Pest in Waterways




   Giant salvinia (Salvinia molesta) is a
free-floating fern with a well-deserved
reputation as one of the worst aquatic
plants in the world.
   The United States Department of          Coachella Canal is Drained for
Agriculture listed it as a noxious weed
in 1983. The plant is native to South       Repairs and Thorough Inspection
America, but has found its way into
several United States waterways from          Concrete repairs were made at two          One section of the canal was filled
North Carolina to Hawaii, including         locations and most of the lined portions   to above normal capacity, and served
portions of the Colorado River.             of the Coachella Canal were inspected      as a reservoir to fill orders while work
   Mature plants weave themselves           during the last week in July.              was completed.
into a thick mat that excludes oxygen         To allow for repairs and inspections       Although there were interruptions in
and light. Under ideal conditions giant     the diversion of water into it from the    deliveries while repairs and inspections
salvinia has the ability to double its      All-American Canal was stopped for         were made, these were minor.
mat size in about a week.                   several days, which allowed the              Two concrete sections of 100 and
                  (Continued on Page 2)     waterway to drain almost entirely.         50 feet were replaced, about 30 miles
                                                                                       west of where the canal begins.
                                                                                                         (Continued on Page 4)

                                                                                        2003 Groundwater Pumping in
                                                                                         the Lower Coachella Valley
                                                                                         Pumper              AF*      %
                                                                                         CVWD                27.0 15.7
                                                                                         Indio               19.0 11.0
                        BRIDGE—Construction
      BIDDERS ON A BRIDGE—Construction
                        BRIDGE                                                           Coachella           17.0 9.9
      firm representatives seeking a contract to                                         Agriculture         62.5 36.3
      line the earthen portions of the Coachella
      Canal attended a pre-bid meeting July 29.                                          Aquaculture         15.0 8.7
      Bids will be submitted August 26. About                                            Golf Courses        24.0 13.9
      35 miles of the canal will be lined with
      concrete. (See article on Page 3)
                                                                                         Other                7.5 4.5
                                                                                        *1,000 acre-feet. 172,000 AF total
Page 2                                                                                                                      August 2004


No Silver Lining Was Found During Canal Inspection
              by Steve Robbins                             It’s also near the amount of water      In most cases, however, we will be
     general manager-chief engineer                     found underground in the lower           using coffer dams or other techniques
   Except for those who rely upon it                    Coachella Valley (Thermal subarea)       so the canal’s water level will have to
for irrigation water, I suspect most                    aquifer—estimated at 19.4 million        be lowered only partially, if at all.
of the valley takes the Coachella                       acre-feet to a depth of 1,000 feet.        So while some interruptions appear
Canal for granted, especially people                       Had the 17 million acre-feet been     unavoidable in the future, they will
who do not live or work close to it.                    pumped out of the ground instead         be kept to an absolute minimum.
   Without this important waterway,                     of delivered by canal, farming here        Coachella Valley’s aquifer made it
however, the area’s history since                       as we know it would be on the            possible for those who settled in this
                                                        verge of extinction, assuming it had     area to do so. Without groundwater,
1949 would be very different, and
                                                        not already ceased to be viable.         there would have been no beginning.
little would appear as it does today.
                                                           Naturally, some water would have        To ensure that we have a promising
   Since deliveries began, nearly 17
                                                        found its way from the upper valley      future, however, means preserving
million acre-feet of water has been
                                                        into the lower, but 17 million acre-     the aquifer today. Maintaining the
utilized by agriculture and others
                                                        feet represents 60 percent of all the    canal to make sure imported water
for irrigation purposes.
                                                        water in the (Whitewater subbasin)       continues to be available is among the
   This is close to enough water to
                                                        aquifer beneath most of developed        most effective ways to do this.
fulfill the domestic needs of the                        and soon-to-be developed areas.            The chart below is among those
entire population of the state of                          Take that much water out of the       presented during one of the special
California for about two years.                         ground and you have big problems         meetings we are hosting for local
                                                        with the quality of what remained,       growers. These sessions have been
Pest . . .                                              along with significant subsidence.        very informative and show how
(Continued from Page 1)
                                                           I’d venture to say that were it not   quickly this area’s groundwater can
   Mats can grow to a depth of more                     for the canal, Coachella Valley would    be used up—or made unusable—if
than two feet, covering an entire pond,                 be a very inhospitable place.            we do not manage it wisely.
reservoir—even a small lake—blocking                       During recent
out sunlight that other plants need;                    inspections of
using up oxygen that fish, insects and                   the canal we
other aquatic dwellers depend upon.                     found about 50
   Unchecked, giant salvinia clogs up                   locations where
irrigation systems and fouls the water.                 repairs will be
None has yet been discovered in the                     needed, and in a
Coachella Canal, its distribution system                few instances
or valley irrigation ststems, but growers               holes or other
are cautioned to watch for the plant                    damage is in the
and report its presence to officials.                    canal bottom.
                                                           Most of this
                                                        work will be
  Published by Coachella Valley Water District to       performed along
   inform users about governmental actions and
other conditions affecting agricultural water service   the first 49 miles
Volume 8 - Number 7                   August 2004       of the canal, far
          Coachella Valley Water District               from sections
              Post Office Box 1058
               (85-995 Avenue 52)                       where deliveries
              Coachella, CA 92236                       are made.
           Telephone: (760) 398-2651
               Fax: (760) 398-3711                         To make these
           Email: cvwdmail@cvwd.org                     repairs we again
             Website: www.cvwd.org
 Steve Robbins, general manager-chief engineer          will have to
Dennis Mahr, communications & legislative director      drain some
                Jack Porrelli, editor
                                                        canal sections.
August 2004                                                                                                              Page 3


Contractors Eager                                                                        Water Advisory
To Bid On Canal                                                                          Group Includes
   Lining about 35 miles of still earthen
portions of the Coachella Canal will                                                     Agricultural Rep
cost about $80 million, according to
                                                                                            An outgrowth of the discussions
the latest estimates, with a significant
                                                                                         between Coachella Valley Water
portion of that going toward actual
                                                                                         District and the cities of Indio and
construction.
                                                                                         Coachella about the lower valley
   Bids for the lining—which in reality is     BY THE NUMBERS . . . Coachella
the construction of a new, concrete-                                                     replenishment assessment charge
                                             Canal Lining project manager Wayne
lined canal segment that will replace                                                    was the creation of a Joint Water
                                             Dahl reviews some of the statistics with
the current earthen sections—are due                                                     Policy Advisory Committee.
                                             contractors during a July 29 pre-bid
by August 26. So a pre-bid meeting at                                                       A panel of 13 representatives is
                                             meeting at the water district.
the water district’s Coachella facilities                                                being recommended, with one of
attracted a big crowd from contractors                                                   the committee members officially
                                                After factoring in water that will be
and subcontractors.                                                                      representing agricultural interests.
                                             used for environmental mitigation, the         Several of the members will be
   Those who attended also spent several
                                             project will net about 26,000 acre-feet     appointed by CVWD’s board of
hours touring the canal by bus, getting
                                             that currently is lost to seepage.          directors, who have not yet done
a first-hand look at the environmental
issues and other concerns that will have       A portion of this saved water will go     so but have recommendations from
to be addressed by the project.              to fulfill a treaty between the federal      general manager-chief engineer
   The current schedule calls for the        government and Indian tribes. The           Steve Robbins.
contract to be awarded on Sept 14., so       balance goes to the San Diego County           Among those the CVWD board
it is expected that actual construction      Water Authority, a condition of the         will appoint is the representative
will begin this year.                        Quantification Settlement Agreement.         from the agricultural industry.
                                                                                            Anyone interested in the position
CV Groundwater Is A Major Focus of                                                       is encouraged to contact CVWD.
                                                                                         Other representatives will include
Latest Ag Water Conservation Sessions                                                    Indio (2), Coachella (2), La Quinta,
                                                                                         CVWD (2), Indian tribes, Building
  Two sessions in July, sponsored by            During the next meeting Ben              Industry Association, golf courses,
the water district and conducted by          Olson, of Olson Engineering Systems,        Riverside County and aquaculture.
JMLord, Inc., focused on the value of        reported that when all expenses are
protecting the aquifer and the benefits       factored in, costs for
from switching from groundwater to           using groundwater
canal water for irrigation purposes.         instead of imported
  The meetings go to a once-a-month          canal water are
schedule beginning this month. The           more than double.
next session is Aug. 18. All meetings           The next session
are on the third Wednesday of the            focuses on the past,
month, at noon, at the water district’s      present and future
Coachella facilities.                        of the Colorado
  On July 21 Dave Ringel, a consultant       River, with Steve
                                                                                  Aquatard
to the district on the Lower Valley          Jones of the Bureau
Replenishment Assessment, reiterated         of Reclamation as
negative impacts on the aquifer—and          the guest speaker.
farming—if overdraft is not curtailed.          There is no charge
                                                                                  Salinity increases dramatically after the
The chart at right demonstrates how          to attend and lunch
                                                                                  water has been used to irrigate crops
agricultural drainage affects salinity.      is included.
Page 4                                                                                                         August 2004

Canal Repairs . . .
(Continued from Page 1)
  Between 80 and 90 percent of the
two, 49- and 39-mile concrete-lined
sections of the canal were inspected
while the repairs were being made.
  Earthen sections of the waterway
were not inspected because they are
being replaced by a parallel, concrete
canal, the construction of which could
begin before the end of this year.
  Silt dredging also was performed at
some sections of the canal.
  Diversions into the canal began at 5
p.m. on Monday, July 26, and by 6
a.m. Wednesday some sections were
                                           Once the canal was back to normal,     CV Water Symposium
                                         water district personnel turned their
completely drained. These areas were     attention to another important form      Is Planned For October
“dry” until 1 p.m. Friday, but by the    of maintenance by restocking areas of      Details were being finalized as Farm
end of the day the canal was filled and   the waterway with grass-eating carp.     Water Watch went to press, but the
fully operational.                         A special, sterilized breed is used.   water district is organizing a valleywide
                                                                                  water symposium for late October.
                                                                                    Various agencies and stakeholders
                                                                                  are being invited to participate. Policy
                                                                                  makers and representatives from many
                                                                                  diverse groups are expected to discuss
                                                                                  a wide variety of water-related issues.

                                                                                  Drought Continues to
                                                                                  Take Toll on Colorado
                                                                                    Lake Mead was at 13.95 million
                                                                                  acre-feet—54 percent of capacity–as
                                                                                  of late July with no signs that an end
                                                                                  to the drought is near. The Colorado
                                                                                  River for April through July is projected
                                                                                  to have flows of 3.6 million acre-feet,
                                                                                  which is 45 percent of its average.

Coachella Valley Water District                                                                      Presort Standard
Post Office Box 1058                                                                                 U.S. POSTAGE
Coachella, CA 92236                                                                                      PAID
                                                                                                     Permit No. 20
                                                                                                    Coachella, Calif.
                                                                                                         92236

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:7
posted:7/6/2011
language:English
pages:4