SYNTHETIC CANAL LINING EVALUATION PROJECT€¦ · shotcrete will stick when sprayed on to the liner...
Transcript of SYNTHETIC CANAL LINING EVALUATION PROJECT€¦ · shotcrete will stick when sprayed on to the liner...
SYNTHETIC CANAL LINING
EVALUATION PROJECT
USCID Water Management Conference
Meeting Irrigation Demands in a Water-Challenged Environment
SCADA and Technology: Tools to Improve Production
Fort Collins, Colorado
September 28 - October 1, 2010
Eric Leigh Extension Associate
Askar Karimov Graduate Student
Guy Fipps
Professor and Extension Agricultural Engineer
Director, ITC
Irrigation Technology Center
Texas AgriLife Extension Service
Department of Biological and Agricultural Engineering
Texas A&M University, College Station
Project based upon work supported by the Cooperative State Research, Education, and
Extension Service, U.S. Department of Agriculture, under Agreement No. 2005‐45048‐03208
For program information, see http://riogrande.tamu.edu
Canal Lining Evaluation
Program
Annual evaluations
and ratings to
determine durability
and long-term
viability of canal
lining
Ensure continued water savings
Help districts select durable canal lining material
Develop guidelines for preventing damage and maintaining performance in such areas as:
vandalism material installation maintenance/repair
Purpose of Lining Evaluations
Evaluation Methodology
Bureau of Reclamation used a general
rating methodology in their 10 year
study of canal liners on rocky segments
Canal Lining Demonstration Project,
Year 10 Final Report, 2002 (R-02-03)
Authors: Jay Swihart, Jack Haynes
Evaluation Methodology
Conducted seepage loss (ponding) tests
and collected cost data
Used a rating scale:
Excellent
Very Good
Good
Fair
Removed
Previous work for a regional water planning
effort: 1999-2002
Rating system for the condition of
concrete lined canals
Synthetic Canal Lining
Rating Evaluation
General performance ratings
Identified 28 lining segments, totaling 20 miles in 7 irrigation districts with 6 different lining materials
Inspections began in 2005
Initially conducted every six months, but little
change was observed
In 2006, switched to once a year during the winter months
Activities
Table 1. Descriptions of lining material components
Most damage observed occurred
from District maintenance activities (mowing and cleaning
out vegetation and sedimentation with heavy
equipment)
UV Light
Animals
Vandalism
Product failure
Range of performance results
Excellent performance is with a geo-membrane overlaid
with a protective barrier (2-3 inches of shotcrete)
Has not required maintenance
Hairline cracks but no problems to-date
Liners with a Protective Barrier
Considerations
Polyester liner has rough fibrous surface for
shotcrete to adhere to.
PVC liner has a slick surface. Required an
additional wire mesh and support system to
hold shotcrete
Performed pre- and post- re-lining seepage loss tests on
Lateral A canal of Hidalgo County Irrigation District No.2
7 mile long section of concrete canal in poor condition
was re-lined with Polyester/shotcrete
Significant Water Savings
pre-lining test – September 2002
Lining project completed – October 2004
First post-lining test – November 2004
Second post-lining test – July 2005
Water losses were reduced after lining up to 94%
Before 1-month after 82% 8-months after
1.36 gal/ft2/day 0.27 gal/ft2/day 0.09 gal/ft2/day
134 ac-ft/mi/yr 24.7 ac-ft/mi/yr 8.6 ac-ft/mi/yr
Significant Water Savings
More susceptible to damage; performance varied
significantly
Amount of damage varied by location; remote areas
performed better than in high traffic areas
Liners without a Protective Barrier
Polypropylene
Good performance (Rating of Excellent to Good)
Applied to existing concrete canals
Some installation problems observed
Polypropylene cont.
Wrinkles could accelerate sedimentation and loose
material can get hung on and damaged
1-foot wide concrete sections poured on top to keep
liner in place and provide access point s for sediment
removal
PVC Alloy
Excellent to Good performance
No major damage
Top exposed areas were damage
EPDM rubber
Poor performance (Rating of Excellent to Serious
Problems)
Problems observed: vandalism, mowing damage,
rotting, inadvertent damage, vegetation under the
material
Very susceptible to animal punctures
Significantly weakened by UV
EPDM rubber cont.
Polyurethane
Worst performance (Rating of Excellent to
Serious Problems)
Severe UV damage (layers are peeling off walls)
Polyurethane
On-site manufacturing requires handling of
dangerous chemicals
Inconsistency in product thickness
No maintenance since installation
Results
EPDM and Polyurethane liners ranged from
good performance to having serious problems
The PVC alloy is the toughest of the 4 liners
installed without a protective barrier
Without question, the best lining system is a
synthetic liner with a protective barrier of
shotcrete.
Considerations when planning new lining projects
Lining Installation
the methods used to overlap and mend/seam the layers
of lining material together
the methods used for attaching the material to the canal
walls, around structures, and to the top of the levee (top
anchor)
the total width of the liner and extension
on top of the levee (“top anchor”) in
relation to the normal and maximum
operating depth of the canals
Use of a Protective Barrier
Increases cost, but these costs may be
offset by the reduction in costs of
maintenance and repairs over the life of
the project.
An important consideration is the ability
shotcrete to adhere to the liner
Use of a Protective Barrier
The polyester material has small fibers (similar
to the harden side of Velcro) to which the
shotcrete will stick when sprayed on to the liner
The PVC liner has a smooth texture to which the
shotcrete will not stick, and a wire mesh needs
to be used on the top of the liner to provide grip
and added reinforcement.
Maintenance
A regular inspection and maintenance program
is important so that repairs can be completed on
a time basis.
Districts should consider having their personnel
trained to performed the repair and maintenance
which sometimes requires specialized
equipment, and similar glues and adhesives
used during the installation process.
Removing sediment from lined canals may be more
difficult due to the limitations of using heavy machinery,
and may require increased manual labor
Conclusions Regular maintenance is required for all non-covered
materials
Inspections should be carried out al least once a year during non-irrigation season (December-January)
The materials without a shotcrete layer are exposed to vandalism and other damage, and may be inadvertently damaged by animals/people
Poor installation of any of the materials makes the product more susceptible to vandalism by leaving folds and loose areas that are easy to cut
Conclusions
• Most damage has occurred on the exposed areas of the
liner and top side walls of the canal from cuts made with
a sharp object (probably intentional vandalism).
• In areas where kids are playing, swimming in the canals,
or being mischievous, intentional and unintentional
vandalism will occur.
• Vultures have been reported to pick at the seams on the
EPDM Rubber; animal hoofs can cut some liners.
Firestone Has developed 3 new types of rubber
liners In 2009, three segments were lined with
these EPDM materials in Adams Garden ID
Canal Lining
Evaluation
Report
June 29, 2009
Report is on the website of the
Irrigation District
Engineering and Assistance Program
Irrigation Technology Center
http://idea.tamu.edu