SYNTHETIC CANAL LINING EVALUATION PROJECT

Transcription

1 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

2 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 For program information, see

3 Canal Lining Evaluation Program Annual evaluations and ratings to determine durability and long-term viability of canal lining

4 Purpose of Lining Evaluations 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

5 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

6 Evaluation Methodology Conducted seepage loss (ponding) tests and collected cost data Used a rating scale: Excellent Very Good Good Fair Removed

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8 Previous work for a regional water planning effort: Rating system for the condition of concrete lined canals

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12 Synthetic Canal Lining Rating Evaluation

13 General performance ratings

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16 Activities 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

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18 Table 1. Descriptions of lining material components

19 Most damage observed occurred from District maintenance activities (mowing and cleaning out vegetation and sedimentation with heavy equipment) UV Light Animals Vandalism Product failure

20 Range of performance results

21 Liners with a Protective Barrier 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

22 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

23 Significant Water Savings 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

24 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/ft 2 /day 0.27 gal/ft 2 /day 0.09 gal/ft 2 /day 134 ac-ft/mi/yr 24.7 ac-ft/mi/yr 8.6 ac-ft/mi/yr

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27 Liners without a Protective Barrier More susceptible to damage; performance varied significantly Amount of damage varied by location; remote areas performed better than in high traffic areas

28 Polypropylene Good performance (Rating of Excellent to Good) Applied to existing concrete canals Some installation problems observed

29 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

30 PVC Alloy Excellent to Good performance No major damage Top exposed areas were damage

31 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

32 EPDM rubber cont.

33 Polyurethane Worst performance (Rating of Excellent to Serious Problems) Severe UV damage (layers are peeling off walls)

34 Polyurethane On-site manufacturing requires handling of dangerous chemicals Inconsistency in product thickness No maintenance since installation

35 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.

36 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)

37 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

38 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

39 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.

40 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.

41 Removing sediment from lined canals may be more difficult due to the limitations of using heavy machinery, and may require increased manual labor

42 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

43 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.

44 Firestone Has developed 3 new types of rubber liners In 2009, three segments were lined with these EPDM materials in Adams Garden ID

45 Canal Lining Evaluation Report June 29, 2009

46 Report is on the website of the Irrigation District Engineering and Assistance Program Irrigation Technology Center