The newest post and image entries are on top of the page. Scroll from the bottom upwards to follow the flow status timeline of the Ruaha River per location

No significant flow in Mbarali downstream of weir on October 30, 2021, which corresponds with near zero flow in Mabarali upstream of confluence. (Click on image to enlarge)

Flow Mbarali at New NAFCO Headworks re-established (October 20, 2021)

Flow over New NAFCO weir re-eastablished on October 20, 2021. The suspected zero flow would have contradicted with the large drainage flow from the Rice Plain (>8 cumecs) and the temporary drying of the weir seems to have been related to some cleaning or other works.

Flushing Operation or Extreme Low Flow to Zero Flow at Mbarali Headworks? (since October 5, 2021)

Flushing or diversion exercise Mbarali or (near) Zero flow status at New NAFCO Headwork still continuous on October 18, 2021.
The exposed riverbed (left image) at the weir on October 15 and October 5, 2021 (below) has not yet remotely been observed on Sentinel images (since 2015). Compare sentinel images with high resolution image June 23, 2019. and image of August 29, 2021 below.
Drainage flow in Mbarali Branch close to confluence with Ruaha River on October 8, 2021. Drainage from Kimani and Ruaha Branches rather than Mbarali, see flow details Mbarali at New NAFCO headworks on October 5, below.
Part of Mbarali Riverbed dried (first remote observation) and dry canal, on October 5, 2021 either for flushing Mbarali Primary Canal entrance through sluice or due to zero flow at Mbarali. The drainage from the Mbarali River close to the confluence with the Ruaha (several kilometres) is still visible on October 8, 2021, but seems to originate from the Kimani and Ruaha branches joining the Mbarali channel.
Compare New NAFCO Mbarali headworks on October 5, 2021 with lowest flow Mbarali below of 1.4 cumecs on September 14, 2017. For detail headworks see above.
Drainage Mbarali close to confluence still holds water in branch canal on September 3, 2021. Compare high resolution image June 25, 2009, below.
Turbulence of flow over crest further reduced on September 5, 2021. Minor drainage flow from New NAFCO headworks (yellow circle and arrow flow direction). Mbarali Primary Canal clearly diverting water.
Zero Overflow or Near Zero Overflow Mbarali Headworks (New NAFCO) on August 26, 2021
Compare August 19, 2021 Drainage Mbarali with drainage flow June 25, 2009 with some water in tributary at bottom right.
Zero Flow or near zero flow. 1.15km upstream from confluence with Ruaha River. Compare with 10m resolution near infrared image Sentinel 2, assessed Zero Flow on September 24, 2019.
Reduced drainage from Mbarali River to Ruaha on June 25, 2009 (left), November 15, 2013 (centre left), September 26, 2014 (centre right) and zero flow on November 21, 2013. (Click on Image to Enlarge)

Sentinel 2 image (S2A) on August 19, 2021 overflow over Mbarali NEW NAFCO headworks further dropping (see previoius image) and less than 3 cumecs.

Mabarali Headworks (New NAFCO) on June 23, 2019 with representation weir detail on Sentinel-2 (S2B) near infra red image on same date. The flow turbulence of the weir is clearly visible.
Estimated Overflow over Mbarali weir (New NAFCO) on July 27, 2021 (image right) is less than the ~3 cumecs which is the overflow on June 23 2019, relected by Sentinel 2 image on the left (5m resolution).
Flow indicators: 1. water level – flow primary canal ~ freeboard or exposure side slope, 2. Submersion divide wall 3. width and turbulence overflow weir 4. Turbulence drop collected overflow right bank section weir appr. 3.5cumecs(?) 5. width overflow and turbulence end sill stilling basin.
Estimated overflow 1 to 2 cumecs (divide wall exposure) compare with August 23, 2011. Primary Canal diversion 3 to 4 cumecs.
Overflow 3 to 4 cumecs, diversion primary canals 1.3 to 2.3cumecs.
Overflow 2.5 to 3.5 cumecs, diversion 1.2 to 2.2cumecs.
Overflow 1 to 2 cumecs, diversion primary canal ~ 2 cumecs
Zero Overflow weir, diversion primary canal ~ 1.4 cumecs