SMALL DAMS PETITS BARRAGES

Fig. 6.11 – Small earthfill dam with weir gauge installed at the exit of the internal
drainage system (L < 200m)
At small dams with some hundreds meters in length, it is usually recommendable
installing two triangular weir gauges at the downstream toe, in order to measure the seepage
water contribution from both abutments separately. But this separation can only be attained
with the construction of an internal barrier at the drainage blanket, in order to divide the
seepage coming from the right abutment from that coming from the left abutment, as can be
seeing in Fig. 6.12.
Fig. 6.12 – Small earthfill dam with two weir gauges installed at the exit of the internal
drainage system length in the range of some hundreds of meters.
For small dams of similar length but with a swamp area at the downstream toe, it is
usually recommendable installing two triangular weir gauges at the downstream toe, in order
to measure the leakage water from both abutments separately. But this separation can only be
attained with the construction of two internal barriers at the drainage blanket, in both sides of
the swamp area, in order to allow the measurement the leakage coming from the right
abutment from that coming from the left abutment, as can be seeing in Fig.6.13
Fig.6.13 – Small earthfill dam with two weir gauges installed at the exit of the internal
drainage system, in both sides of the downstream swamp area.
For small dams with more than some hundreds of meters in length it is usually necessary
to measure the water exiting from the internal drainage in more than two points. In this case
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