Sustainable Irrigation Water Harvesting and Storage

 

Background

Historically, agriculture has faced challenges traceable to unpredictable rainfall patterns which is a characteristic of the dominant arid and semi-arid climate. In Kenya the ASAL areas occupy 80-89% of the country as shown in figure 1. As a consequence of climate change, the frequency and severity of drought periods appear to be increasing mainly in these ASAL areas.

With a national average rainfall of 400 mm, the country needs to harvest and store adequate water for agriculture and other uses through investment in water management infrastructure across the country. Notably, the arid counties are characterized by a network of ephemeral streams as shown in figure 2 that only flow during the rainy seasons. These streams provide a unique opportunity of increasing access to water for communities in these regions through construction of inline water harvesting and storage structures. Additionally, in areas where there are no streams, water harvesting using small ponds or what has come to be known as household water pans has increased access to water for farming communities.

The authority is implementing large water pans for use by communities and household water pans across the country. The community water pans have a capacity of 30,000 to 250,000m3 where neighboring farmers using portable pumps abstract water for irrigation. The focus has been desilting the existing large water pans and small dams as well as construct new one in the arid areas. The list of large water pans by the Authority can be found here Large Dams

The household water pan concept entails providing water harvesting reservoirs at household level whose capacity is 1000-3000m3. The Authority excavates the water pans while farmers are required to fence and utilize the stored water for irrigation. Learning from the Operation Mwolyo Out (OMO) initiative in Yatta, it has been demonstrated that using a combination of a localised reservoir and efficient irrigation system households can sustain their livelihoods in arid areas.

Objectives

  • Realise localized water access solution by providing water harvesting and storage reservoirs for irrigation purposes at the household level.
  • The target is to harness surface water (runoff) resulting from rainfall received in the reservoir areas in the arid counties.
  • Use harvested water for agricultural production.

Benefits of this approach

  • The programme is easy to achieve due to less complications in land acquisition for construction
  • Due to the distribution, the project has a wide coverage benefiting a large population in vast areas
  • The programme purely depends on runoff therefore a suitable water access solution for areas without rivers
  • The investment on conveyance is minimal and is incurred by farmers.

Identification

Identification of the sites for construction will carried out by engineers under the supervision of the Authority working closely with local administration and opinion leaders. The following will considered: –

  • Location will ensure that rainfall runoff is collected,
  • Site is free from hard rock as much as possible to eliminate use of a breakers
  • Farmer is willing to cede land for the construction of the pan
  • Farmer will take responsibility of utilizing the water and fence for safety purposes
  • Depending on the size of land farmers have a choice of selecting a pan ranging from 1000-3000m3

The proposed crops to be grown using the installed system include maize (green maize), tomatoes, onions, capsicums, bananas and watermelons. It is projected that productivity for all the other proposed crops will increase by more than 100%; with tomatoes being the highest at 240%. This way the project will increase food security access to water for the benefiting households thus contributing to the “BIG FOUR” agenda of the government.

 

Last Update: November 11, 2021
November 11, 2021 126 adminIrrigation
Total 0 Votes
0

Tell us how can we improve this post?

+ = Verify Human or Spambot ?

Log In is required for submitting new question.

Log In is required for submitting new question.

Scroll to Top