Rainfall has been reduced in the upper catchments of both the Juba and Shabelle rivers over the past week. River levels on the Shabelle in Gode have been reported as decreasing since Saturday 14th, but there still remains a high risk of flooding in the areas around Belet Weyne and Bulo Burti as flood waters in the Ethiopian catchments move downstream. The risk of floods in the lower reaches of the Shabelle is also high, though actual downstream river levels will be reduced by catchment attenuation processes.
The levels on the Juba are reported as being high and are rising but the flood risk for the coming week remains moderate.
The rainfall forecast for the coming week is for up to 75 mm of rain in the Ethiopian catchments and for between 30-45 mm in the riverine areas of Somalia. Cumulative rainfall for the Gu season remains below average. Low levels of antecedent soil moisture reduces the risk of flooding caused by in-country precipitation and flood risk will be mainly driven by high river levels in Ethiopia. The already high flood levels in Ethiopia and forecasted additional rainfall in these catchments imposes a high flood risk on the Shabelle in particular.
Flooding in Belet Weyne has drowned the gauge and prevented readings being taken. The Shabelle forecast is based upon a simulated trend and cannot be considered quantitatively accurate. River levels may fluctuate over the coming week in response to fresh inputs from Ethiopia. Localised flooding is expected in the lower reaches as the flood wave travels down stream. Predicted levels at downstream stations will be reduced by irrigation and out of bank flow. The risk of severe flooding remains high throughout the Shabelle's reaches and close monitoring of local conditions is required.
Figure 1: Predicted water levels on Shabelle
SHABELLE & JUBA GU 2005 FLOW BULLETIN NO.6 17th May – 23rd May, 2005
River levels have fluctuated over the last week, but the overall trend is for increasing stage on the Juba over the coming week. The levels predicted at downstream stations will be reduced due to irrigation and dheshek filling throughout the course of the river. The flood risk remains moderate on the Juba but is increasing.
This bulletin is produced by FAO Somalia Water and Land Information Management (SWALIM) Project and USGS/FEWS NET Somalia. SWALIM and USGS/FEWS NET acknowledge Care Somalia, CINS & SCUK for their continued assistance.