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A network of consultants in: water resources, hydrology, hydraulics, hydrogeology and water quality
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Arid Zone Hydrogeology
Arid and semi-arid zones present special problems to hydrologists. Describing the hydrological balance is difficult as very little of the potential evaporation demand need be satisfied. Only a small proportion of the rainfall becomes runoff except in extreme storms. Also, rainfall tends to be highly variable in arid regions both in time and space, which leads to very high variability of runoff.
 

Well in oasis

 Groundwater can be a major source of water. Aquifers range from: localised occurrences replenished by current ephemeral runoff , to regional systems containing pluvial(fossil) water. Localised resources include shallow alluvial, stream-related deposits, which are used throughout the world by rural peoples. Elsewhere, the thin superficial weathered hard rocks are exploited by dug wells and more recently slim air-hammer drilled boreholes. Regional aquifer systems are amenable to centralised management. They are multi-aquifer sedimentary sequencies which may be consolidated or not and typically have no significant recharge from rainfall.
Experience shows sustainable development of all groundwater, local or regional, must have regard to hydrogeology ,socio- economics and environmental issues.

GROUNDWATER DEVELOPMENT:

Our principals include ex-advisers in hydrogeology to the British Aid Programme and have experience throughout the developing world, this includes:

Localised aquifer studies:

Botswana , Zimbabwe:
Ephemeral so-called sand rivers occur throughout the arid regions. Our principals are active in advising on the development of sand river deposits .In Botswana on the Shashi river several town supplies have been created. In Zimbabwe a scheme for using the Sabi river groundwater supplies is underway using EC funding.

Well , Borehole Management Techniques
Well design and yield enhancement techniques have been developed and utilised by our Principals. Hydrofracturing ,Scavanger and Collector wells have been used to enhance yields in Pakistan and Bangladesh as well as Africa.

Software has been written which greatly assists analysis and prediction of well and borehole performance in real-life situations.

Regional Studies:

Botswana, Zimbabwe, Malawi, Sri-Lanka:
Our principals led studies of the regional groundwater system of weathered crystalline basement . Better means for safe development and exploitation, including collector wells, were derived and utilised in all the above countries.