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• • 23 CCESS long and 1/i inch wide should be measured and recorded. Access to the dam site as well as to Larger cracks or cracking systems should bemonitored.(See $ operating equipment and monitoring Chapter 12.)The ends of cracks or cracking systems should devices must be available. Lost keys be marked with a pin or stake to allow measurement of any should be replaced and broken locks growth. repaired or replaced. 4.5-4 DISPLACEMENTS OR SLIDES Displacements or slides often indi- SCARP cate a structural problem. The dam can no longer maintain its shape. ,VAUCTED Areas that require inspection can be These areas should be thoroughly �«f(F obstructed by tumbleweeds,trash,or examined for surrounding cracks, rock slides. These obstructions need ` to especially uphill from the displace- to be burned or shoveled out.A lot of ment or scarp. The entire area should ' snakes in an area can make the area be probed to determine the condition " unsafe. If the dam site cannot be of the surface materials. The hand inspected when the snakes are inac- level should be used to locate accu- tive, special safety precautions are Side view rately the top of the scarp (x). This recommended. will allow progressive deterioration INUNDATED Provisions must be made to shut off to be detected.The base width should outlet flows and/or pump out low w—r— be measured or accurately paced. +. areas where water ponds in order to t- t Any seepage flows should be located Finspect the area thoroughly. When a r— ,v and the quantity measured or esti- �� worsening condition is suspected,the mated. It is extremely important to inspection must be done immediately y note if the seepage water is muddy or in spite of water user needs. if it is carrying off soil material. It is _ Front view helpful if the type of soil can be iden- 4,5-2 • UNEVEN SURFACES tifted, i.e., sand, clay, etc. SWALE OR BOWS Swale and bows are depressions and q 5-5 LEAKAGE AREAS bulges that are evenly distributed over a large area. A swale is also CONCENTRATED Exact location and quantity of flow referred to as a dished area.Thissub- FLOW must be determined as accurately as SwALE tle type of change from a continuous possible. The water should be care- surface can be indicative of a serious fully examined to see if it is carrying I Y structural problem. Sighting can be embankment materials. Ajar sample used to identify the condition.Dished WATER is recommended. At a minimum,the BOw or bowed areas should be closely r= -- inspector should allow the water to i --- examined forany developing cracking run over a cupped hand for 15 sec- pattern. The location of the mis- onds,then see if any soil grains have aligned area along the dam's length, Side view beendeposited.Waterthatlooksvery plus the size of area affected and estimated amount of clear can be carrying quite a few soil deviation,or offset should be recorded. If the condition will T---1-- particles. The area around the exit show up on a photograph, a picture should be taken. T point should be probed to determine _ . _ _ if area surrounds the leak. BULGE AND A bulge or depression is a localized Quantity measurements should be DEPRESSION condition. This should be closely i begun to allow accurate comparison. inspected for adjacent cracking pat- 1 This will allow increases to be detec- BULGE terns. Probing should be done to find Front view ted and recorded. out if any excessive moisture or soft SATURATED AREAS Location and extent of wet or satur- material is present, ated areas must be recorded along DEPRESSION with any measurable flow quantities. WATER These areas are usually "squishy' Y 4.5-3 CRACKS Cracks or various sizes can be found when walked on.There can be a visible in earth, concrete, asphalt, and steel flow on the surface. These areas i portions of the dam. They always ! should be probed to determine how require close up observation and soft the material has become. If very should usually be recorded.Cracks in Side View soft, it may lead to local slides. The earthwork should be investigated with presence of vegetation which flour- the probe to determine their depth ishes in wet places can indicate a t and whether they may be associated saturated area.� -r - � with excess moisture. Measurements should be made to determine the width,depth,and displacement. Nor- '. mally,cracks in earth less than 10 feet From view