RESERVOIR SEDIMENTATION ASSESSMENT GUIDELINE - Aneel

Reservoir Sedimentation Assessment GuidelineSedimentdischargetotalIndirectTopo-bathymetric survey for thereservoir, determination of depositsvolume and trap efficiency in the lakeCollection of suspended and bedmaterial, concentration analysis,granulometric analysis, temperaturemeasurement, hydraulic parameters andcomputation of total discharge –Einstein’s method modified andColby’s method simplified1) For small reservoirs, it allowsfor the computation of bedsediment2) For large reservoirs, it allowsfor the computation of totalsedimentSeveral kinds of equipment –pumping, equipment using bottlesand bags, being instantaneouspoint, points by integration andvertical integrators (in Brazil ismainly used the North-Americanseries U-59, DH-48, DH-59, D-49, P-61 and bag sampler)Several measurement or suspended sampling equipment may be classified indifferent kinds, such as:• Instantaneous or integrators, where the instantaneous quickly gets the sampling orread them, while integrators admit sampling in a few seconds through a beak or abill, storing it in a recipient;• Portable or fixed, where portable ones are manually operated, by pole or shrill, oreven fixed to a boat, while the fixed ones are installed in a adequate structure, eitheron a bridge or at the bed;• Beak or with bill, where the beak are of pumping or other, and those using bills arethe portable ones furnished with bottles, plastic recipient or plastic bag;• Punctual instantaneous, punctual by integration and by vertical integration, wherepunctual instantaneous are cylinder-like with a device for capturing the samplingsending a messenger/weight that closes the valves. The punctual by integrationcollects sampling in a few seconds at a vertical point. The vertical integrators or indeep waters collect sampling by moving the equipment along vertical in a steadymovement that may be in a single way or back and forward from surface to bottom.• Horizontal tube sampler, of bottle, collapsible bag, pumping, integration,photoelectrical, nuclear, optical ultrasonic flowmeter, dispersion ultrasonic,Doppler Ultrasonic Flowmeter– the horizontal sampler is a punctual instantaneousone. The bottle sampler is hydrodinamically built and has a cavity for inserting acollection bottle; the sampling is performed through a bill that may report severaldiameters (1/4”, 3/16” e 1/8”) while the air is expelled through a tube. Thecollapsible bag sampler is also hydrodinamically built and has an aluminum-maderecipient for holding the plastic bag, which is compressed in order to expel the air;its capacity is greater than the bottle’s capacity and it also uses exchangeable bills.The pumping device may be settled on a boat or installed at the bed; normally, it isused a hose furnished with a beak or a bill adjusted for allowing in the sampling;the pumping is monitored according to the stream velocity, and there are severalkinds of such equipment. The equipment working through integration is bottle orbag collapsible . The photoelectrical and the nuclear ones operate through light andrays, respectively, through a constant intensity source. The optical and thedispersion ultrasonic work with sources that produce ultrasonic rays that arereceived by adequate equipment. The Doppler Ultrasonic Flowmeter uses Doppler19ANEEL – Brazilian Electricity Regulatory Agency / SIH – Hydrologic Studies and Information Department