Topographic Satellite Mapping

Topographic maps consist of elevation contours and planimetric detail of varied scale, and serve as general base information for civilian and military use. They represent various things such as physical features, population, political boundaries, climate, economic activities, natural resources, roads, climate, and topography. Traditionally they have been produced by surveyors photographing an area from the air. In more recent years, satellites have been providing the images required to produce more detailed and accurate topographic maps. 
 

Sources

Related Content

Article

Interview with Basuti Gerty Bolo

Interview with Basuti Gerty Bolo

Photo of Basuti Gerty Bolo
Basuti Gerty Bolo dreamt of space science and of becoming an astronaut when she was only 8 years old. She then wanted to be a pilot, before studying space applications and space and atmospheric science.  Her curiosity for space science was sparked by an interest in knowing more about unexplained mysteries of things happening in space, such as the cause of some plane crashes. Basuti works exceptionally hard to disseminate space knowledge. She is an Endowed Chair for Educational Technologies at Africa University in Zimbabwe, a UNOOSA Space for Women Network mentor, and is starting a space for women and girls network called Space4Women_AfricaDreamers to spread space awareness and promote gender equality.
Read More

Can space technologies help improve WASH provision in camps and informal settlements?

Can space technologies help improve WASH provision in camps and informal settlements?

Informal settlement

The Human Right to water and sanitation

What does your morning routine look like? For most readers I’d assume you use the toilet, wash your hands, and maybe take a shower.  However, do you ever stop to consider the water you use to shower, or the soap you use to wash your hands? Often, especially in developed countries, these things are taken for granted, rightly considering access to adequate water, sanitation, and hygiene (WASH) as basic Human Rights (Figure 1).

Read More

Est ce que les Technologies Spatiales Peuvent Améliorer les Provisions WASH dans les Camps et Quartiers Informels

Est ce que les Technologies Spatiales Peuvent Améliorer les Provisions WASH dans les Camps et Quartiers Informels

Informal settlement

Le droit humain à l'eau et à l'assainissement 

À quoi ressemble votre routine matinale ? Pour la plupart des lecteurs, je suppose que vous utilisez les toilettes, vous vous lavez les mains et peut-être que vous prenez une douche. Cependant, vous arrive-t-il de vous arrêter pour réfléchir à l'eau que vous utilisez sous la douche ou au savon que vous utilisez pour vous laver les mains ?

Read More

Interview with Basuti Gerty Bolo

Interview with Basuti Gerty Bolo

Photo of Basuti Gerty Bolo
Basuti Gerty Bolo dreamt of space science and of becoming an astronaut when she was only 8 years old. She then wanted to be a pilot, before studying space applications and space and atmospheric science.  Her curiosity for space science was sparked by an interest in knowing more about unexplained mysteries of things happening in space, such as the cause of some plane crashes. Basuti works exceptionally hard to disseminate space knowledge. She is an Endowed Chair for Educational Technologies at Africa University in Zimbabwe, a UNOOSA Space for Women Network mentor, and is starting a space for women and girls network called Space4Women_AfricaDreamers to spread space awareness and promote gender equality.
Read More

Space-based Solution

Water suitability map (Samburu County, Kenya) - in development

Addressed challenge(s)
Collaborating actors (stakeholders, professionals, young professionals or Indigenous voices)
Suggested solution

Background information on the geology of Kenya

The geology of Kenya shows Metamorphic rocks in the western part due to high metamorphic processes. The Great Rift Valley is a plate boundary.

Tertiary and Quaternary Volcanic Rocks: East African Rift System: volcanic activity during these periods

Geology map of Kenya
Fig.1: National Atlas of Kenya - Geological Map. (n.d.). European Commission, Joint Research Centre. ​

Resources used for addressing the challenge

Map of community locations

Map of important community locations
Figure 2: Map of locations of the community, from where water access would be needed in the vicinity.
Legend of the map of community locations

Software

  • QGIS: A Free and Open Source Geographic Information System. Version 3.32.3 / Version 3.28.11 LTR. 
  • ArcGIS Pro. Version ArcGIS Pro 3.

Data sources

Publications used for methodology and background research

see references indicated below.

Steps outlining the solution

  1. To find where water is situated, compare a topographic map with the Normalised Differentiated Vegetation Index (NDVI). Recharge occurs where water accumulates and hence vegetation is available/the healthiest at the driest times. This step could be implemented using Google Earth Engine.
     

    Topographic map of Samburu province in Kenya
    Figure 3: Topographic map of Samburu province in Kenya. Credit: Topographic Map (2023)

     

    Map showing the Samburu county Normalised difference vegetation index
    Figure 4: NDVI made with QGIS. Version 3.32.3 / Version 3.28.11 LTR.
  2. Develop a geology map and potentially a geophysical survey (mineral composition). Mineral data and geophysical characteristics are well mapped in Kenya. It is likely that the geology in Kenya requires a basement rock drilling using air hammers / air compressors and pneumatic hammering.
     
    Figure 3: Zoom into Samburu county from the National Atlas of Kenya - Geological Map. (n.d.). European Commission, Joint Research Centre.
    Figure 5: Zoom into Samburu county at the National Atlas of Kenya - Geological Map. (n.d.). European Commission, Joint Research Centre. Orange: Basement rock, Yellow Quarternary Sediments.

     

  3. The communities are located in the South-West of Samburu County. The geology in the area is mostly magmatic and metamorphic. This suggests that the ground has very low permeability. However, near the location of the communities there are two springs. These springs point to an aquifer in the area, where a well for the communities in the area could be developed. ---
    Map of water sources in Samburu county, Kenya.
    Figure 6: Water sources in the Samburu county. Map provided by Kenya Space Agency. Source: G. de Sourza, Dept. Geography, University of Nairobi, J. Keza, Ministry of Water Development.

     
  4. A desk study compares the geology with the topography
     
    Geology map of Samburu County Krhoda et al. (2015).
    Figure 7: Geology of Samburu County Krhoda et al. (2015).

     

Samburu county elevation map
Figure 8: Elevation Map made with QGIS. Version 3.32.3 / Version 3.28.11 LTR.

Location of water sources

The area of interest has two springs, which are natural groundwater outflow in the surface.

Map showing the Samburu county water points
Figure 9: Elevation Map made with QGIS. Version 3.32.3 / Version 3.28.11 LTR.

 

Groundwater resources

Aquifer in magmatic/metamorphic basement: moderate productivity

  • magmatic rocks have low permeability
  • Groundwater recharge is low

Ideal outcome: A possible groundwater source exists near the communities homes and borehole could be developed

Map showing possible groundwater resources in the Samburu County based on the geology
Figure 10. Possible groundwater resources in the Samburu County based on the geology.

 

Next steps to be taken with external actors

  1. Work with hydrogeologists to prepare a borehole siting report as well as an Environmental Impact Assessment. Groundwater relief has some trusted hydrogeologists in their network in Kenya who could implement that and submit the information to the Kenya Water Resources Agency.
     
  2. Kenya Water Resources Agency needs to grant permission for drilling.
     
  3. Drilling and pumping test: A contractor performs drilling and a pumping test. The latter is to identify the appropriate pump to be used.

  4. Groundwater level, type of aquifer, groundwater recharge, groundwater vulnerability.

 

Other solutions based on space technology and geophysics

List of commonly used geophysical methods in hydrology and geophysical properties they sense
Source: Binley et al., 2015.

 

Electromagnetic and seismic solutions

Electromagnetic and seismic solutions, image showing saprolite thickness in meters, the depth to bedrock in meters, and the water capacity of the aquifer in m.
Figure 11: Good results in hard rock terrains: metamorphic and magnetic rock areas. Source: Flinchum et al. (2018).

 

Sources

Barasa, M., Crane, E., Upton, K., Ó Dochartaigh, B.É. & Bellwood-Howard, I. (2018): Africa Groundwater Atlas: Hydrogeology of Kenya. British Geological Survey. Accessed [22.09.2023]. http://earthwise.bgs.ac.uk/index.php/Hydrogeology_of_Kenya

Kuria, Z. (2013): Groundwater Distribution and Aquifer Characteristics in Kenya. Developments in Earth Surface Processes, Elsevier. 16, 8, p. 83-107.

Krhoda, G., Nyandega, I. & Amimo, M. (2015): Geophysical investigations of Suyien Earthdam in Maralal, Samburu County, Kenya. International Journal of Physical Sciences. 2, p.33-49.

Makinouchi, T., Koyaguchi, T., Matsuda, T., Mitsushio, H. & Ishida, S. (1984): GEOLOGY OF  THE NACHOLA AREA AND THE SAMBURU HILLS, WEST OF BARAGOI, NORTHERN KENYA. African Study Monographs, Supplementary Issue 2, p. 15-44.

Touber, L. (1986): Landforms and solid of samburu District, Kenya. A site evaluation for rangeland use. The Winand Staring Centre for Integrated Land, Soil and Water Research. Report 6. 

Data sources (maps)

National Atlas of Kenya - Geological Map. (n.d.). European Commission, Joint Research Centre. https://esdac.jrc.ec.europa.eu/content/national-atlas-kenya-geological-map (visited: 19.10.2021). 

Samburu District - Type and Location of Water Sources, Key Landforms, and Soils (Symbols - See Map 11). (n.d.). European Commission, Joint Research Centre. https://esdac.jrc.ec.europa.eu/content/samburu-district-type-and-location-water-sources-key-landforms-and-soils-symbols-see-map-11 (visited: 19.10.2021)

Links to Space4Water resources that are part of the solution
Map with y axis being latitude and x axis being longitude indicatingdecadal precipitation in Kenya

Rainwater harvesting in semi-arid to arid climate - in development

Image showing hands reaching into the night sky. Source: ESA

Identify locations for the creation of sand dams - in development

Keywords (for the solution)
Topographic Satellite MappingNormalized Difference Vegetation Index (NDVI)Bored wellGroundwaterGroundwater abstractionWellSpring
Climate Zone (addressed by the solution)
Dry
Habitat (addressed by the solution)
Region/Country (the solution was designed for, if any)
Kenya
Relevant SDGs