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6.3A Page 17 If any reach has an elevation lower than the anticipated high water elevation, steps should be taken to provide emergency topping to raise the levee grade to forecasted flood heights. The following is a brief description of the various methods that may be used to increase dike height. 1. Sack Toppinq - Sack topping may be used to raise the crown of the levee about three feet. The sacks should be laid stretch-wise or along the levee crest for the first layer, crosswise for the second layer, and so on. Sacks should be lapped at least one-third either way and well mauled into place. When properly sacked and tamped, one sack will give about three to four inches of topping. 2. Lumber and Sack Topping - A common method of raising low reaches during emergencies is by the use of lumber and sack topping. This method utilizes wooden panels on the watershed side of the levee crown. The panels are reinforced on the landward side of sandbags. Stakes, 2"x4"x6' and spaced 6 feet apart, should be driven into the levee on the bayside of the crown. Panels shall then be attached to the side of the stakes facing away from the channel. The wall should then be backed with a sufficient number of sand bags to support the panels against the anticipated high water. In extreme cases, a three- foot topping may be provided if properly braced behind with sacks and earth. In some instances, it may be practical to back up the panels with tamped earth, obtained in the vicinity, in lieu of sandbags. VIII. Operation and Maintenance A. Maintenance The City shall at all times provide such maintenance as may be required to ensure serviceability of the flood control structures in time of flood. Full responsibility for making repairs is placed on the Public Works Services Department under the direction of the Public Works Services Director. All repairs shall be made upon consultation with the Engineering & Construction Division and in accordance with standard engineering practice. No change or alteration shall be made to any feature without prior evaluation by a licensed engineer and authorization by the City that such alteration will not adversely affect the stability and operational integrity of the protective facilities. B. Inspections Levee inspections will include the following: 1. Levees will be visually inspected every six months for signs of erosion, settlement, or other conditions indicating the necessity for maintenance. 10 Apri12008