Document nke8aNBxJz0o4xBeaOnokZq9X

REPORT ON ASBESTOS/CEMENT PIPE USE AT THE SAN GABRIEL VALLEY WATER COMPANY, CALIFORNIA PREPARED FORi THE A/C PIPE PRODUCERS ASSOCIATION 1600 WILSON BOULEVARD ARLINGTON, VA 22209 PREPARED BY: WADE MILLER ASSOCIATES, INC, 6260 15TH PLACE NORTH ARLINGTON, VA 22205 APRIL 20, 1982 CAPCO JEN 0023591 REPORT ON ASBESTOS/CEMENT PIPE USE AT THE SAN GABRIEL VALLEY WATER COMPANY, CALIFORNIA Introduction The San Gabriel Valley Water Company, located in El Monte, California, is the third of ten water systems studied under the Municipal Analysis Program of the A/C Pipe Producers Associa tion. In this detailed site visit, as well as the other nine, the objective was to investigate the use of A/C pipe from every perspective. The broad functional categories covered by this fact-finding mission are as follows: Institutional Operational - Decisionmaking, Specification, and Procurement - Installation and Testing - Operation and Maintenance - Repair and Replacement - Detection and prevention Financial Each of these categories of information is discussed in detail in this report. Background on the San Gabriel Valley Site Visit The two day site visit to the San Gabriel Valley Water Company was conducted on January 11-12, 1982. Officials interviewed during the course of the visit included the following: Ivan G. Holmberg, Vice President & General Manager G. J. Black, General Superintendent W. F. Gray, Distribution Superintendent F. A. Lo Guidice, Chief Engineer R. L. Watts, Purchasing Agent Initially, Mr. Holmberg questioned carefully the purpose of the survey and the uses that would be made of the data. He also participated in most of the interviews, either directly or by i CAPCO JEN 0023592 2- - remaining in the room when others were being interviewed. How ever, both he and his staff participated fully in the survey and gave their time willingly. In general, they were quite pleased with the performance of A/C pipe although they did not express any particular interest in working further with the Association. This is not unusual since they do not participate in AWWA or other associations. Institutional and Background Information The San Gabriel Valley Water Company is a subsidiary of the Utility Investment Company of Nevada, a privately owned utility holding company. San Gabriel dates from 1935 and has grown steadily over the years. In 1979, it purchased the Arizona Water Company for $5.6 million. San Gabriel is divided into two districts: Los Angeles County and Fontana. Jointly, they serve about 210,000 persons with 60,000 service connections with 125 mgd of water (including untreated water sold for irrigation of cropland). About 70 per cent of the raw water supply is groundwater, with the remaining 30 percent drawn from surface waters purchased from the Metro politan Water District of Southern California (MWDSC). The groundwater is chlorinated only; surface water is filtered and chlorinated. In both cases, the waters can be classified as non-aggressive. The MWDSC obtains its surface water supply from the California Aqueduct, which conveys water from the Colorado River to Southern California. Of the two divisions, L. A. County is by far the largest. San Gabriel's overall management is located in El Monte, which is also the headquarters for L. A. County operations. However, the majority of the system's annual growth rate of 1000 connec tions is occurring in the Fontana service area. Major engineer ing decisions, such as pipe purchasing, are made largely by Mr. Holmberg and apply to both divisions. A copy of the Company's organization chart is attached. The Los Angeles County Division is divided into five opera ting groups headed by the General Superintendent, Jerry Black. Bill Gray is chiefly responsible for the 14 man group that hand les maintenance of the distribution system including main break repair. San Gabriel is a regulated public water utility under the jurisdiction of the California Public Utilities Commission (PUC). It is required annually to submit a report to the PUC providing separate and combined financial data for the L.A. County and Fontana districts. A complete copy of the system's 1980 PUC report was provided at the time of the site visit. The Transmission and Distribution System The San Gabriel system is a heavy user of A/C pipe, having i' CAPCO JEN 0023593 V:- 3- - about 450 miles of A/C, 240 miles of cement lined and coated steel, 40 miles of iron pipe and 1 mile of PVC. The steel pipe is used largely for lines larger than 16 inch diameter, and for those lines laid within 10 feet of a sewer or under roadways or rail lines. The 1980 PUC report lists the footage of A/C by size as follows: Pipe Diameter (inches) Feet Installed Percent of Tota 3 446 >0.1 4 372,443 16.1 6 1,008,874 43.7 8 496,238 21.5 10 282,027 12.3 12 84,523 3.7 14 26,257 0.6 16 46,660 2.0 18 1,313 >0.1 The usage distribution of pipe materials also is detailed in the PUC report: Pipe Material Amount (feet) cast iron cast iron (cement lined) concrete copper riveted steel standard screw screw or welded casing cement asbestos welded steel plastic 23,815 216,784 10,477 632 106,206 255,148 332,678 2,307,246 1,137,652 4,515 TOTAL 4,345,203 As of December 31, 1980, A/C comprised 53.1 percent of the total footage. Steel pipe was second with 42 percent of the system. Cast iron footage is minimal and is not growing. Some PVC is used, usually in very small sizes (2 inch), but Holmberg showed little inclination toward expanding the system's use of PVC. In fact, he cited a recent incident at the Arizona Water Company where PVC pipe was substituted for an A/C pipe order by the supplier. Although the substitution was ultimately accepted, it resulted in a policy specifically banning such changes in the future. Service connections usually are installed with polybutylene pipe. Some problems have been experienced with these, related to faulty resins manufactured in 1974-1975. However, the system continues to use this material, but the quality of pipe receiv ed is monitored carefully. CAPCO JEN 0023594 -4- Most of the cast iron ir the system is older pipe which has experienced some problems witn internal and external corrosion. San Gabriel has found that cement lining and wrapping of steel pipe is adequate protection under their conditions of mildly agressive water and soils. They attribute the excellent perfor mance of A/C in the system to the quality and integrity of the pipe, plus close control of contractor-installers. OPERATIONS Specification, Decisionmaking, and Procurement San Gabriel purchases pipe directly from the suppliers on an annual contract basis, with supplemental purchases as requir ed. The system contracts out the installation to a select group of contractors, who pick up the required materials from the Company's supply yards. Installation contractors are required to have extensive experience with pipeline construction and they must be prequalified for the system's approved bidders list. There are currently 6 approved contractors on this list. As an added incentive to attract competent contractors, the system stresses prompt payment of contractor invoices, forwarding pay ment within 15 days of billing. In lieu of writing highly detailed specifications which can then be bid by all nominally qualified pipe suppliers and con tractors, the system exercises a high degree of selectivity for both pipe suppliers and installers. Bidding is highly restrict ed as a means of maintaining quality control and also to stand ardize the materials and construction techniques within the sys tem. Only two A/C pipe manufacturers, Johns-Manvilie and Certain Teed, are allowed to bid A/C pipe; foreign manufacturers are specifically excluded. Materials and installation specifica tions are written around the applicable ASTM and AWWA standards, plus those of J-M and Certain Teed. In 1981, the latter was the sole source supplier of pipe used by San Gabriel. Within the boundaries of the limited and rigorous prequali fication procedure, purchasing decisions are made based on the price quoted by the lowest bidder. A/C pipe has been found by San Gabriel to be highly competitive in sizes up to and includ ing 16 inches. Consideration is being given to using larger A/C pipe more extensively because of non competitive conditions in the steel pipe market. System officials noted that U.S. Steel has a "virtual monopoly" in many of the larger steel pipe sizes. Design Considerations For the most part, San Gabriel uses Class 150 A/C pipe in the valley portions of its service area where system pressures range from 70-80 psi. Hillside areas can have pressures as high as 125 psi and sometimes require the use of Class 200 pipe. The standard design practice requires 30 inches or more of cover. Where possible, the pipe network is looped to avoid dead end and ii CAPCO JEN 0023595 I I. stagnant conditions. Other design requirements largely paral lel those suggested by J-M and Certain Teed. Truck delivery of pipe is required and material is carefully inspected when received. Installation and Testing Contractors are required to install A/C pipe in accordance with the AWWA C603 standard. To facilitate pipe location, the system requires the installation of 18 gauge copper wire on the top center of the pipeline. Pipe is normally installed in the shoulder of or immediately adjacent to roadways because some problems have occurred from tree root intrusion into pipe that is installed in yards, greenspaces, and parklands. Holmberg has a laminated tree root with an ingrown corporation stop in his office. It is labeled, "Automatic Corp Stop Remover." This display received an AWWA award in 1970. With only two exceptions in recent years, San Gabriel has assumed direct control and responsibility for all pipe installa tions within its service area. System officials noted they can install pipe at a lower cost than developers can and with fewer ensuing problems. Data on the amount of A/C and steel pipe installed annually since 1970 was also provided and is tabulated below. The rate of increase of A/C pipe usage has been relatively flat in the L. A. County Division, but continues to increase sharply in the Fontana Divison, reflecting continued strong growth of the ser vice area. Steel pipe is retaining a minor percentage of the total, particularly in the Fontana system. Year Los Angeles County A/C Steel Fontana A/C Steel 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 21,697 18,739 25,859 23,341 22,801 19,606 27,893 27,134 39,938 37,555 23,961 17,945 25,421 21,629 5,502 14,154 1,845 4,470 9,635 3,304 3,370 15,872 13,133 12,429 19,406 47,117 16,403 28,213 19,768 17,403 28,814 17,624 72,082 58,490 65,247 67,049 7,451 4,696 710 9,945 204 90 80 213 633 207 15,802 4,512 Virtually all of the A/C pipe is accounted for by 6, 8 and 10 inch diameter pipe. At the Los Angeles County Division, 8 inch pipe is used most frequently, followed closely by 6 inch. The reverse is true at Fontana, where 6 inch pipe predominates. In 1980 for example, 8 inch A/C pipe installed in the L.A. CAPCO JEN 0023596 6- - County Division accounted for 47.3 percent of the total A/C foot age, versus 17.4 percent for 6 inch and 1^.8 percent for 10 inch. At Fontana, 6 inch pipe accounted for 49.5 percent of the total A/C footage, versus 28.7 percent for 8 inch and 16.6 per cent for ,10 inch. Although the sharp upward trend in pipe usage by this utility has flattened out somewhat, it will continue to purchase significant quantities of pipe each year. A/C pipe is highly price competitive and, as detailed later, an outstanding performer in this system. Also, the A/C pipe and health issue has not been particularly active. Mr. Holmberg noted that the most interest occurred one or two years ago when they received several calls from water customers. Pipe Handling Procedures Contractors are expected to follow handling procedures recommended by the pipe manufacturers. The contractor is responsible for any damage to the pipe after it is picked up at the Company's supply yard. San Gabriel requires truck shipment of the pipe. Rail shipment is not allowed. Field machining of the pipe is avoided by using MOA sections where needed. Trenching, Bedding, and Backfilling Minimum trench width specified is 18 inches for pipe of inch or less diameter. Trenches for larger pipe must exceed nominal diameter of the pipe by 12 inches. Minimum cover requirements are as follows: Depth of Top of Main Pipe Size From Flow Line of Gutter 8 the 4" - 6" 8" 10" 12" & Larger 36" 42" 46" 48" Sand backfilling is required only where the trench has been overcut. Otherwise, the specification only forbids backfilling with rocks or lumpy material greater than 3 inches in diameter closer than 12 inches to the pipe. Compaction is by water jet ting after the trench has been backfilled to within 12 inches of the surface. Tapping San Gabriel allows direct tapping and threading of A/C pipe with the following restrictions: 1. No 3/4 inch taps are allowed on 4 inch A/C. 2. No one inch taps are allowed on 4 or 6 inch A/C. i i CAPCO JEN 0023597 -7- 3. No direct taps are allowed on Class 100 A/C pipe regardless of size. 4. Where direct taps are not allowed, tapping saddles are required. Wet tapping is normally performed using a Mueller purged tapping machine. In the early 1950's, the system used pretapped couplings but experienced sand fouling of the taps. Disinfection and Pressure Testing A/C pipe at San Gabriel is pressure tested per AWWA specifi cations. No special requirements are imposed in addition to AWWA specs. Contractors are responsible for mainbreaks on newly installed pipe. Attached is a copy of the Company's standard pressure test table. Disinfection and flushing are required as per AWWA standards, local health regulations, and manufacturers' recommendations. Recommended Work Practices Contractors are responsible for following OSHA approved methods for working with A/C pipe. San Gabriel does not train contractors on safe methods of cutting and machining A/C pipe and does not require them to use approved tools other than for hot tapping. Mr. Holmberg was not aware of any AACPP publica tions on Recommended Practices. He requested that the Associa tion send him 12 copies of the booklet. Operation and Maintenance San Gabriel does not collect and analyze main break data. The reason given for this is that the frequency of breaks is so low that the effort is not justified. Mr. Holmberg noted that breaks in the system average about one per month for A/C, and two per month for metallic pipe (cast iron and steel). For the most part, A/C breaks are caused by contractor error during construction of adjacent storm drains or other utilities. Another cause of main breaks is intrusion of tree roots where the pipe passes through greenspace. Current installation prac tices note the location of trees and avoid such areas as park ways when possible. Mainbreaks are repaired using stainless steel repair clamps. Usually, repairs are made by the system's own repair crews, though contractors may be called in on the larger breaks. The comment was made that A/C breaks tend to be quite large as the pipe will often crack or break across its entire cross sec tion when it fails. San Gabriel's 1980 PUC report shows an expenditure of less than $170,000 for maintenance of transmis sion and distribution mains. Total unaccounted for water in the system is about 4 per- i' CAPCO JEN 0023598 8- - cent, including fire flows, street cleaning, contractor usage, and losses from broken mains. Purchased and pumped water is metered carefully and compared with metered water sales to arrive at the 4 percent figure. Because water loss is so low, there is no formal leak detection and repair program in opera tion and none is contemplated at this time. Mr. Holmberg cited service connection failures and improper ly set or stuck valves as the system's principal maintenance problem. The maintenance department has a program of checking valves and taps and has found numerous conditions of incorrectly closed valves and leaking or partially open taps. He also noted that there are no problems with declining flow coefficients with the system's pipe. Rather, flow problems occur where existing mains are not large enough to handle current demands. A/C pipe has performed very well throughout the system. It has survived minor earthquakes without breakage and San Gabriel managers consider it superior in all regards with the exception of beam strength. Mr. Holmberg noted his belief in the flexibility of A/C pipe in earthquake situations and stated a strong preference for 13 foot pipe lengths and rubber ring sealed couplings. He also stated, ."if A/C does have a fault, it is brittleness--we get large breaks." He emphasized the low cost, ease and economy of installation, superior earthquake performance, and immunity to corrosion as the primary reasons why San Gabriel will continue to install A/C pipe. FINANCIAL The San Gabriel Valley Water Company appears to be a finan cially healthy and well managed organization. Total operating expenses in 1980 were just under $7 million. Operating reven ues, including metered water revenues, fire protection charges, and irrigation amounted to $10.56 million. Net income after interest expense and taxes was $1.65 million, a 15.6 percent return on sales. Bonded indebtedness as of the end of 1980 was $11 million, which was 36 percent of the water plant value of $30.5 million. Pipe is depreciated on a 50 year schedule. Where developers do not install system extensions (the usual case), they contribute to the cost of any extension. In turn, they are refunded 22 percent of gross revenues from the new service area until the initial contribution is refunded. This is a California PUC requirement. San Gabriel also finances system extensions out of retained earnings. San Gabriel managers believe they are purchasing and installing pipe in a very cost effective manner. They provided the winning bid data for their major 1981 A/C pipe purchase tabu lated on the next page: i CAPCO JEN 0023599 ! t Size 4" 6" 8" 10" 12" 14" 16" Approx. Quantity 1,500' 25,000' 25,000' 12,000' 3,000' 500' 1,500' Price, $/ft. Class 150 Class 200 2.05 2.87 4.24 6.21 8.07 9.92 12.06 2.28 3.30 4.61 7.22 9.43 10.98 14.00 These prices include delivery to the El Monte supply yard. No installation cost data was provided. No bid data was provided for steel, PVC, or ductile iron pipe. System officials stated that A/C is quite cost competitive up to 16 inches in size and is becoming more so in the larger sizes due to monopolistic con ditions in the steel pipe market. CONCLUSIONS San Gabriel has had outstanding experience with A/C pipe. The very low main break and leakage rates speak well for the pipe and the system's installation practices. System managers are enthusiastic in their praise of A/C pipe and obviously expect to make it their first choice in the future. Moreover, uncompetitive supplier conditions in the larger diameters, where steel pipe is currently being used, present a marketing opportun ity for suppliers of A/C transmission pipe. This very well managed utility is a perfect example of the attributes of A/C pipe that can be portrayed effectively in pro duct advertising based on case studies. It is recommended that the Association seek approval from San Gabriel (through Ivan Holmberg) for a case history advertisement which could be pub lished in the AWWA Journal, Public Works, or other major trade journals. CAPCO JEN 0023600