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Project 153 - Project Report - 2000-09-01 PROJECT REPORT PROJECT #153 SEWER LATERAL ROOT INTRUSION STUDY Robin B Hamers Manager/District Engineer Q�OFESS/0N 4.47 . 11441 /I N0. (<,9N 2G? C7 ( RC 31720 s EXP (1/2000 * •/VIt e %()P'CAtIF�P September 2000 Table of Contents Purpose of Project II. Background III. Root Growth in Sewers IV Removing Roots V Review of Areas Televised VI. List of Addresses Contacted VII. Sample Letter Mailed to Property Owner VIII. Conclusion I. Purpose The purpose of the project is to review video tapes of the District's sewer mains and observe and tabulate the incidence of roots in property owner laterals at their point of connection with the main line. A notification is then made to the property owner to advise them that maintenance of the lateral is recommended. II. Background District ordinances require the property owner be responsible for keeping the sewer lateral running free and clear from the building all the way to its point of connection with the District main line. Typically the District main line is located in the center of the street, usually about 30 feet from the property line. When a property owner notifies the District that their lateral is backing up the District field crews first verify the main line in the street is running free and clear Next, they run the jetter hose in the main line to insure it is completely clear When there is no doubt the main line is fine and the problem is definitely in the lateral, the crew meets with the property owner to advise them of the possible problems in their lateral. The District Inspector and engineering staff usually provide follow-up consultation to assist the property owner in arranging for maintenance or reconstruction of the lateral. Although the District has very few incidences of blocked sewer flow in the main line due to root intrusion, incidence of lateral blockage due to roots is more frequent. The biggest offender is ficus trees which have very aggressive root systems. III. Root Growth in Sewers When the District runs a camera down the main line, the only part of the property owner lateral that is visible is the connection point or discharge point of the lateral into the main line. Observation of roots at the end of the lateral is an indication that roots are prevalent throughout the lateral. Oftentimes a small ball of roots is observed that over the years may become very dense and restrict flow Roots usually enter the lateral through the joints between pipe sections. Tests completed by the National Institute of Clay Pipe disclosed that roots will not enter a joint if it is properly installed and the trench is properly backfilled, however rarely are actual field conditions this perfect. Pipe joints installed in the late 1940's and early 1950's do not have the same flexibility and soundness of today's jointing system and can easily crack or separate. Once a slight separation in the joint starts to occur roots will penetrate the opening and expand the separation by the entry of more roots and the growth in diameter of the original roots. The slight separation can be caused by imperfect pipe laying methods, improper backfill operations, or earth movement associated with mild earthquakes. IV Removing Roots Once roots are prevalent they must be removed prior to the roots cracking and collapsing the pipe or a backup occurring. Roots can literally strangle a pipe at a joint and root masses can become so dense that they will cause separation of the joints. In either of these occurrences, excavation from the ground surface down to the pipe along with pipe replacement is usually necessary and is very costly The cost will vary depending on the depth of the lateral and whether it is located in a front yard or in the driving lanes of the street. If roots have not yet destroyed the pipe they can either be cut out or killed with a chemical foaming agent. Cutting roots requires the services of a plumbing contractor and once the cutting is completed the roots flow down through the line. Chemical agents kill the roots and the roots remain attached for a period of time, usually at least one month, before they fall off and travel down the line. Chemical agents are readily available in hardware stores and can be introduced by the homeowner Root cutting presents its own problems because it is similar to pruning a tree; the ends split and grow back more dense. Due to this, current thinking is to apply a chemical agent first to kill the roots, then cut them out as soon as the agent has completely invaded the root system. Regardless of the method used, homeowners should perform regular maintenance on the lateral to insure it is running free and clear Today's plumbers have camera equipment and can locate and video problem areas. V Areas Televised Televising Area No. 7 (N/o Adams Ave. W/o Mesa Verde Drive East, E/o West boundary of City of Costa Mesa) 72,000 L.F (Linear Feet) of sewer televised 1325 laterals were observed Televised August 1988 Televising Area No. 2 (N/o Fair Drive, S/o Merrimac Way W/o Harbor Blvd. E/o Fairview Rd.) 22,300 L.F of sewer televised 442 laterals were observed Televised October 1988 Televising Area No. 1 (N/o Presideo Dr S/o Baker St. W/o Mendoza Dr E/o Bristol St.) 38,000 L.F of sewer lines televised 808 Laterals Televised February 1989 VI. List of Addresses contacted PROJECT 1112100-153 SEWER LATERAL ROOT INTRUSION STUDY PHASE I LATERAL UPSTREAM LINE SEGMENT NO. PROPERTY ADDRESS STATION MANHOLE STATION NUMBER 1 1843 Tanager Dr. 1+13 187 L 7.972-973 2 2729 Cardinal Dr 2+86 9 L 7.985-986 3 2717 Cardinal Dr 0+94 46 R 7.986-987 4 1920 Balearic Dr 18+61 92 L 7 1052-7 1051 5 2824 Boa Vista Dr. 3+33 115 L 7 1062-1061 6 2832 Nevis Cir 3+62 215 L 7 1058-1057 7 2824 Nevis Cir 3+59 218 L 7 1058-1057 9 2808 Boa Vista Dr 8+36 108 M 7 1060-1059 10 3062 Club House Rd. 142 L 7 1072-1073 11 3058 Club House Rd. 184 L 7 1072-1073 13 3038 Club House Rd. 78 L 7 1073-1074 14 3034 Club House Rd. 120 L 7 1073-1074 15 2904 Club House Rd. 4+35 280 R 7 1078-1077 16 Timor Dr (Mesa Verde Park) 59 R 7 1080-1134 17 2871 Stromboli 93 R 71090-1091 18 2865 Stromboli 185 R 7 1092-1093 19 1868 Paros Circle 3+74 41 L 7 1099-1098 20 1851 Rhodes Dr 0+44 299 R 7 1100-1091 21 1854 Boa Vista Dr 1+35 97 L 7 1102-1090 22 3054 Java Rd. 10+89 139 R 7 1115-1114 22 3049 Java Rd. 10+15 63 L 7 1115-1114 23 3058 Java Rd. 11+69 12 L 7 1116-1115 24 3060 Java Rd. 12+14 80 L 7 1116-1115 25 3057 Java Rd. 11+99 108 R 7.1116-1115 26 1881 Maui Circle 1+64 214 L 7 1125-1124 27 2983 Java Rd. 0+80 153 L 7 1126-1108 28 2959 Java Rd. 3+96 189 L 7 1127 1126 29 2922 Java Rd. 9+06 56 R 7 1128-1127 30 2970 Maui Circle 0+75 103 R 7 1129-1107 31 2979 Mindanao 2+02 266 L 7 1151-1152 32 2983 Mindanao 0+98 12 L 7 1152-1116 33 1801 Tahiti Dr 1+36 67 R 7 1153-1137 34 1813 Tahiti Dr 9+05 286 R 7 1154-1153 35 1825 Tahiti Dr 7+51 135 R 7 1154-1153 36 1819 Tahiti Dr 8+28 209 R 7 1154-1153 37 1841 Tahiti Dr 4+97 123 L 7 1154-1155 38 1860 Tahiti Dr 2+50 28 R 7 1155-1106 39 1864 Tahiti Dr 1+51 128 R 7 1155-1106 40 1870 Tahiti Dr 0+67 211 R 7 1155-1106 41 3006 Club House Dr 258 L 7.1163-1074 42 3007 Club House Dr 258 R 7 1163-1074 43 3004 Club House Dr 270 L 7 1163-1074 44 3005 Club House Dr 283 R 7 1163-1074 45 3008 Club House Dr 222 L 7 1163-1074 46 3010 Club House Dr. 197 R 7 1163-1074 47 3014 Club House Dr. 159 L 7 1163-1074 48 2816 Nevis Cir 125 L 7 1059-1058 49 1853 Elba Cir 1+05 110 L 7 1096-1093 50 1834 Samar Rd. 6+70 105 R 7 1133-1132 51 1807 Tahiti Dr. 9+95 6 R 7 1153-1137 52 1915 Sumba 1+99 12 L 7 1164-1052 VI. List of Addresses contacted 53 1692 Palau PI. 0+87 270 L 7 1188-1189 54 3014 Club House 125 L 7.1163-1074 55 2580 Carnegie Ave. 5+86 167 R 2.217-205 56 2510 Carnegie Ave. 3+50 37 R 2.220-219 57 2526 Carnegie Ave. 0+74 219 L 2.257-219 58 414 Carnegie Ave. 4+71 63 R 2.257-219 59 2518 Colby Pl. 4+71 78 R 2.258-257 60 2884 Mission Dr. 254 R 1.19-18 61 839 St. Clair St. 4+39 224 L 1.23-22 62 833 St. Clair St. 5+95 67 L 1.23-22 63 834 St. Clair St. 5+59 102 R 1.23-22 64 2858 Drake Ave. 18+09 160 R 1.25-24 65 2869 Drake Ave. 16+95 39 L 1.25-24 66 2865 Drake Ave. 16+29 195 L 1.26-25 67 2734 Drake Ave. 3+55 107 R 1.30-29 68 998 El Camino Dr 6+30 72 R 1 71-70 69 923 Presido Dr 1+22 139 R 1.90-82 70 979 Presido Dr 11+63 188 R 1.94-93 71 1032 Presido Dr 0+45 99 L 1.96-95 72 865 Sonora Rd. 3+87 194 L 1 119-118 73 2761 Portola Dr 7+78 136 L 1 145-144 74 2803 Portola Dr. 7+11 203 L 1 145-144 75 2802 Portola Dr 7+08 205 R 1 145-144 76 2766 Portola Dr 7+71 142 R 1 145-144 VIII. Conclusion District Staff found the project to be very beneficial for the District and the property owners. Notifying the property owners allows them to take remedial steps before the problem expands into a costly break or backup. Having property owners remove small amounts of roots decreases the chances of a large amount of property owner roots from becoming lodged in a District main line. This has happened on a few occasions over the years. Most importantly a sewer backup causes immediate health concerns and disrupts the property owners and District Staff's schedule as it must be immediately resolved. As a service to the residents, District Staff has taken an inventory of all the root control products in the local hardware stores. A list of the products and their prices is on file and is available upon request. Over the last 20 years the incidence of root intrusion in laterals is not frequent, however the trees and root systems are continually growing and expanding. By notifying certain residents of their potential problems along with providing information and recommendations in various publications, the District Staff is being proactive in helping residents avoid sewer problems. When the next full scale District wide televising is started, it is recommended this service be continued.