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deal with sewer flows, groundwater leaks, contaminated substrate, insects, animals, traffic, dangerous gasses and so on. Less-than-ideal environmental conditions are also a challenge in properly applying concrete coatings and affect their long-term performance. Rain, heat, cold, humidity and extremely dry conditions make it difficult to apply coatings on the porous surface of concrete. Increases in surface temperature during the initial coat to bare concrete may cause expansion of air and solvent within the concrete surface resulting in pinholes and bubbling as they escape through the uncured film. Concrete moisture can also cause a substrate side amine blush that is concealed from routine inspection and later results in osmotic blistering in immersion service. Many times the applicator will start with acceptable conditions and changes occur throughout the day that may cause the work to be ruined, or questionable at the very least. Field conditions must be continuously monitored to understand and adjust for their potential effects on the coating system being installed. Often, it is beneficial to control the environment to the extent possible using techniques such as containment, temperature control and dehumidification. Qualification of Applicators Even the very best coating system will fail if not properly installed. Similar to product selection and specification writing, the use of a qualified applicator is a critical element of a successful coatings project. Inexperienced buyers often sort “painting contractors” into one single group. In reality, coating application typically involves very specialized processes and equipment, and the most qualified applicators are often the ones that specialize in a particular area, such as concrete tank linings, manhole coatings, floor coatings or structural steel. Specialization fosters the development of best practices, work efficiency and improved product quality. When the same processes are repeated, mistakes are usually reduced or eliminated, and the process can be continuously improved. Risks are reduced and the odds of success are increased. In contrast, using inexperienced applicators predictably results in a large learning curve. With complex coating and lining systems, this learning curve can be very costly. The best contractor on the last job might not be the best for the next job if the type of coating work to be performed is significantly different than the last time. The applicator’s area of expertise should be a prime consideration when developing a short list of bidders for a project. A good source to find qualified applicators is the manufacturer of the selected products. Generally, they will want to recommend qualified applicators to better ensure the success of their product. Some manufacturers of high-performance coatings only sell to contractors that have gone through some form of a manufacturer training and qualification program to become an “approved” applicator. Requiring the contactor to be a manufacturer-approved applicator is almost always a good idea. Proof of approval should always be in writing from the manufacturer. References and referrals from other past projects should always be required and fully investigated in the applicator selection process. To ensure the “low-bid” is meaningful, final consideration of bidders should be limited to only those that are truly qualified to perform the work. Otherwise, an apparent lower price may only be due to a lack of understanding of the project requirements. Accepting an inappropriately low bid from an inexperienced applicator contractor will predictably result in unsatisfactory results as well as change orders, schedule delays and excessive rework. In-Process Inspection Some coatings applicators do excellent work. Some do not. However, if an applicator knows that all of its work will be inspected thoroughly, it is far more likely to do a good job. Full-time, in-process quality control inspection helps ensure that the selected coating system is properly implemented. Although the utility owner should monitor and inspect the quality of the work, the applicator must be ultimately responsible for its performance, quality control and workmanship. In cases where the owner assigns an inspector, the applicator will often attempt to use the inspector as a gauge for its work. If problems arise, the applicator often responds by saying it was doing what it was told and it passed all inspections, suggesting it is not the problem of the applicator. This undesirable scenario blurs lines of responsibility because the owner’s inspector has inadvertently become part of the applicator’s work process. The system specifier must make it clear in the project procurement documents that the owner reserves the right to inspect, but has no burden or responsibility for the final outcome. It must be clear that quality control is the sole responsibility of the contractor. It is ideal for every coatings applicator to have its own qualified, full-time inspector working at all times during the installation process. Even when an applicator has a qualified inspector, it can still be difficult to always get quality workmanship. The inspector’s paycheck comes from the applicator, which sometimes makes it difficult to perform inspections and report in an effective and unbiased manner. For this reason, on larger or complex projects, it is usually advisable for the owner to hire a qualified NACE-certified coating inspector to monitor the work to ensure project requirements are being followed. This added oversight usually enables the applicator’s inspector to do a better job. However, as previously noted, the owner’s assignment of an inspector should never replace the requirement for the applicator to inspect its own work. Another useful tool to ensure project quality is to require that the applicator utilize a manufacturer’s technical representative to provide field training and verify on a continuous basis that work is being completed in accordance with the manufacturer’s requirements. The manufacturer should inspect storage, surface preparation, mixing, application, testing and should ultimately provide some form of a Certificate of Proper Installation. After all, the manufacturer is the expert with its material and is in the best position to resolve unexpected challenges that develop in the field. To the uniformed, this level of oversight and precaution might seem a little overboard. However, due to their cost and complexity, coatings and linings in wastewater environments have demonstrated an unusually high rate of failure compared with most other construction activities. 38 Water Utility Infrastructure Management November/December 2011
The consequences of failure usually far outweigh the cost and inconvenience of the increased project oversight. Recommendations The ultimate success of a coatings project can be best assured by up-front product evaluation and validation. It is also necessary to spend the time to research and to gain an in-depth understanding of the conditions under which the coating system will be applied and the associated long-term exposure challenges. This knowledge, along with local experience and that of other users, is then applied to establish coating system performance criteria and to develop comprehensive specification of materials and methods. Other important steps to achieve success include qualification of material suppliers and applicators and comprehensive field quality control practices. Jeff Maxcy is a construction manager with CH2M HILL. He graduated from Mississippi State University in 1985 with a BS in Construction Engineering and started working with CH2M HILL in 1987 as a construction inspector. For the past 20 years he has been involved with determining how to specify and install waterproofing materials, concrete restoration materials and coatings properly in a sanitary sewer system. Tom Iseley, Ph.D., P.E., is a Professor and Director of Construction Engineering Management Technology, Purdue School of Engineering & Technology at IUPUI. Iseley has over 35 years of experience in the planning, design and construction of underground infrastructure systems. He served on the faculty of Mississippi State University, Purdue University and Louisiana Tech University. He founded the Trenchless Technology Center at Louisiana Tech and was a founding member of the North American Society for Trenchless Technology. For more information visit www.uimonline.com/info November/December 2011 For more information visit www.uimonline.com/info Water Utility Infrastructure Management 39
Page 2 and 3: For more information visit www.uimo
Page 4 and 5: CONTENTS November/december 2011 COV
Page 6 and 7: 36 34 Teaming Up for Water Delivery
Page 8 and 9: CONTRIBUTORS Pamela A. Malone serve
Page 10 and 11: FROM THE PUBLISHER’S DESK CWC and
Page 12 and 13: NEWS WEFTEC 2011 Attracts Strong Cr
Page 14 and 15: NEWS MEETINGS U.S. Conference of Ma
Page 16 and 17: NEWS LEAK DETECTION Wachs Water Ser
Page 18 and 19: W A S H I N G T O N R E P O R T Mob
Page 20: For more information visit www.uimo
Page 23 and 24: the Wadsworth Mutual Water Company
Page 25 and 26: Water Utility Infrastructure Manage
Page 27 and 28: Background Utility: Douglasville-Do
Page 29 and 30: screen. The ratio of productive, sc
Page 31 and 32: There are common issues across util
Page 33 and 34: P3 Implementation in Canada Public-
Page 35 and 36: Tampa Bay Water, Veolia Water North
Page 37: eports. Future reviews, validation
Page 41 and 42: PROFESSIONAL INDEX Company Website
Page 43 and 44: Uniting the Trenchless World Presen

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