Major flood

Stage = 82cm, Ta = 19.7C, Tw = 14.4C

Yesterday we had a major flood at Takiya River, with stage reaching 1.8m and discharge estimated at 60m3/s (basin area is 19.45km2). Over July 17-18, 127mm of rain fell on already saturated ground, with a peak intensity of 35mm/h. Under these conditions flash floods often occur at Takiya River with stage rising by as much as a metre in a matter of minutes. The hydrograph below shows two other large floods during the past week, both of which exceeded 1.4m in stage.

Unfortunately the depth and velocity of the flow was too high to allow wading of the river and so we could not take a discharge measurement. I have used a sounding weight and cable from the road bridge, but this method is hardly effective and prone to large errors. I need to investigate other methods and instruments to estimate peak flows at Takiya River.