Mapping period: April 29th until May 29th 2015
Surface area: 1.17 km2
Flood prone area: 0.35 km2 (30%)
Population (2012 census): 54,781
Total number of buildings: 9,504
School and hospital buildings: 12
Buildings at risk of flooding: 1,948, of which 12 are school or hospital buildings.
Description and recommendations: The area was first mapped on OpenStreetMap in 2011. This map was updated and improved this spring using aerial drone imagery collected by our team. Drains blocked by trash have worsened the situation in these areas, and houses have been abandoned due to flooding. The area was first mapped on OpenStreetMap in 2011. This map was updated and improved using aerial drone imagery collected by our team.

In the north, Tandale is bordered by the Ng’ombe river, which forms the boundaries with Kijitonyama and Magomeni wards. This part of the ward (comprising largely of Mharitan, Mkunduge and Mtogole subwards) is heavily affected by flooding. The most detrimentally affected parts are the lower grounds along the river Ng’ombe, while the higher grounds are at very limited risk.

Pakacha subward of western Tandale is mainly affected by a stream called Kiboko, which drains the area to join the river Ngo’mbe. The residential buildings along this stream are exceptionally vulnerable to flooding..

In the southern part of the ward, there is a stream that flows from Pakacha to Sokoni and Tumbo subwards to join the river Ng’ombe. The stream is man made and has been reinforced with a lot of packed waste materials along its walls to increase its depth. The height of these materials, however, rarely suffices, and the stream leaves surrounding buildings inaccessible when it rains. There have been many initiatives by local residents to clean the stream, and these efforts have made significant improvements, though often only short-term.

Related post: Drainage in Tandale

Tandale ward before mapping Source: OpenStreetMap

Tandale ward before mapping Source: OpenStreetMap

Tandale ward before mapping Source: OpenStreetMap

Tandale ward before mapping Source: OpenStreetMap