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Development of an extensive irrigation system downstream the Bagré Dam in Burkina Faso 

Background:

The story concerns a extensive irrigation system downstream the Bagré Dam, in Burkina Faso. The Bagré dam was inaugurated in 1994 and the irrigation scheme of the dam lies approximately 150 km south east of Burkina Faso's capital, Ouagadougou within the department of Bagré in Boulgou province.

Developing hydropower and large-scale irrigated agriculture were the two main objectives in constructing the Bagré dam. The dam's irrigation objective aims to address food security for the local and national population. Traditional cereal farming on rain-fed land is the main source of livelihood in the region, along with the raising of livestock, including pastoralism. Improving and increasing the production of rice is a key component of the government's national development policies.

Here is the link to the presentation that was made for the hand-in-hand meeting (on Earth Map).

Region:

Burkina Faso, West Africa 

Topic:

Surface Water, Irrigation Systems

Findings:

The vegetation, water and demographic data compiled in Earth Map can show the direct consequences of the construction of a dam and the expansion of irrigation systems, such as the production of improved rice seed  in the Bagré area which  is helping local rice-producing smallholders in Bagré become self-sufficient in rice production as well as providing  new employment opportunities.

i) Looking at the satellite images in December 2019 (Figure 1) we can observe that different land covers such as water, savanna and agricultural plantations can be easily differentiated with the satellite image colours. Big infrastructures such as damns are clearly spotted in the image;

(ii) The agriculture expansion can be identified from images in 1984, 1998, 2002 and 2018 (Figure 2) as a direct consequence of the construction of the dam in 1994. In 2019, the extension of irrigated agriculture is approximately 5 000 ha;

(iii) New permanent (7 782 ha) and new seasonal (13 685 ha) flooded areas (Figure 3) have been identified within the timeframe between 1984 and 2018 due to the building of the dam;

(iv) Population in the area (Figure 4) has more than doubled in 15 years (from 65 711 inhabitants in 2000 to 15 8402 inhabitants in 2015) which most likely is related to local small-hold farmers producing their own rice and their households becoming more resilient.

Figure 1: Screenshot of the Imagery Compare Tool, with zoom into the Bagré Dam. Sentinel 2 cloud free mosaic images are represented in December 2019 . In the image, water (purple colour), savanna (yellow/green colour) and agricultural plantations (orange colour) can be identified based on satellite image colours.

Figure 2: Vegetation intensity with zoom-in to the irrigation system, images in 1984, 1998, 2002 and 2018 (based on Landsat - Greenest Pixel Yearly 1984-2018).

Figure 3: New permanent and new seasonal flooded areas between 1984-2018 (based on the European Commission’s Joint Research Centre Global Surface Water Explorer

Figure 4: Population data (drawn from GHSL: Global Human Settlement Layers, Population Grid 1975-1990-2000-2015).