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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