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RIVERSIDE PUBLIC UTILITIES Board Memorandum PUBLIC UTILITIES BOARD OF PUBLIC UTILITIES DATE: April 1, 2011 ITEM NO: 3 SUBJECT: REPLACE ANCHORS ON THE VISTA — MT. VIEW 69 KV TRANSMISSION LINE WORK ORDER NO. 1113535 ISSUE: Board of Public Utilities approval is requested for Work Order No. 1113535. RECOMMENDATIONS: That the Board of Public Utilities: 1. Approve the estimated capital expenditure of $125,000 for Work Order No. 1113535 to replace existing anchors and down guys on the Vista— Mt. View 69 kV transmission line; and 2. Authorize the General Manager to issue change orders to the construction contract awarded for this project in an amount not to exceed 20% of the original contract amount of$85,300. BACKGROUND: On Sunday, January 9, 2011, at 6:39 AM the Vista — Mt. View 69 kV transmission line tripped off line. The SCE operator at Vista Substation tested the line at 6:43 AM, in accordance with standing orders. The test was unsuccessful. The troubleshooter patrolled the line and at 7:32 AM reported multiple transmission poles down in the Santa Ana river bottom northerly of Palo Verde Lane along the bicycle trail. Three overhead crews were called out to perform emergency repairs. Crews replaced two poles at their existing locations and installed three new poles at new locations with better access to replace four other failed poles. An additional pole was replaced due to deterioration resulting from termite damage. The failed anchor was replaced and a second anchor was installed at a new pole location. Investigation determined that an anchor rod failed due to corrosion at Pole 25141 J. The sudden release of tension snapped insulators at three poles and caused five poles to snap at ground line. Detailed visual inspections of the wood poles, insulators and anchors and intrusive inspections of the wood poles on the Vista — Mt. View 69 kV transmission line were last conducted in 2009 by contract crews in accordance with GO 165. The failed anchor had been rated in good condition based on a visual inspection. Staff prepared Work Order No. 1113535 to replace the existing 79 anchors and 90 down guys on this transmission line. Staff will also evaluate available non-destructive testing options on the existing anchors to determine the most effective method for identifying defects or corrosion. Each existing anchor will be pull tested to its design strength before removal 18 inches below grade. Change order authorization of 20% of the original contract construction amount of$85,300 or$17,060, is requested as the area is undeveloped and has limited vehicle access and unknown interference or conditions may be encountered. In order to keep the construction on schedule for this critical transmission line, staff is requesting authorization ahead of time in case it necessitates the need for unexpected change orders and having to request re-approval.