space
About UNEP
space
space
United Nations Environment Programme
Division of Technology, Industry and Economics
top image
space
space space space
space
space

Newsletter and Technical Publications

<Sourcebook of Alternative Technologies for Freshwater Augumentation in Africa>

2.1.4 Groundwater Abstraction in Urban Residential Areas

Technical Description

This is the abstraction of groundwater through boreholes, by private householders or water supply agencies.

Extent of Use

The technique is extensively used in a number of countries in Africa. In rural areas, it may be the only reliable source of water supply. In urban centres, it augments conventional municipal supplies.

Operation and Maintenance

The operation and maintenance requirements for groundwater abstraction systems usually relate to type of pumping system used. For poorly constructed boreholes, collapse may be experienced.

Level of Involvement

Both household and water supply agencies make use of this technology.

Costs

Borehole drilling and components costs have been estimated to be about $3 000 for a typical installation. Energy costs depend on source of energy used, usually the cost of electricity.

Effectiveness of the Technology

Household use of groundwater reduces demand for treated urban water. It is also efficient for industrial use since each industry can treat the water to meet its own requirements.

Suitability

This technology is suitable in all areas with groundwater reserves, in particular, during droughts.

Environmental Benefits

There could be environmental damage from over pumping as the water table recedes. In years of water shortage, this over-pumping may negatively affect the groundwater discharge into rivers, lakes and reservoirs.

Advantages

The advantages of this technology include its site-specificity; no significant delivery (reticulation) systems are necessary. The technology may be used where urban services are poor or unreliable.

Disadvantages

Over pumping may lead to ground subsidence. Subsidence is of great concern in crowded urban areas. Further, groundwater is susceptible to contamination from wastes.

Cultural Acceptability

Generally, there are no cultural problems with the use of groundwater supplies.

Further Development of the Technology

Techniques for the rapid assessment of safe yield to avoid over pumping are required..

Information Sources

Simpson, G.C. 1990. Research into Groundwater Abstraction in Residential Areas. Vol 1. Water Research Commission Report No. 211/1/90, Division of Building Technology, CSIR, Pretoria.

Back

Table of ContentsTable of Contents Next

  • Brochure
  • IETC Brochure


  • International Year of Forests
  • International Year of Forests


  • World Environment Day
  • ??????


  • UNEP Campaign
  • UNite to Combat Climate Change