Hydrogeology of the Nakuru-Elementeita-Naivasha watershed (Kenyan Rift)

Abstract

The study area is located between longitudes 35° 52' to 36° 40' E and latitudes 0°10'to 0°50' S. It is found within Nakuru district, and has area coverage of about 10100sq.km. The Nakuru- Elmenteita-Naivasha area is accessed by the Nairobi Naivasha-Elmentita-Nakuru-Uganda international tarmac road and railway line, and many local routes. A hydrogeological study with sufficient hydrogeological and hydrogeochemical information and maps that can serve as a basis for water resource development and monitoring is very important for such an area where groundwater is highly abstracted for various activities, such as for industries, irrigation in many large scale mechanized farms, animal rearing, domestic use, and locally for recreation. The high abstraction of groundwater, the waste disposal mechanism and irrigation return water will cause a significant change in quality of the groundwater with time unless awareness is created and protective measures are practiced. Therefore, the objective of the study was to assess the general hydrogeological condition in the area, address some of the problems seen mainly due to man's interference. The basic geological, hydrogeological, and hydt$eochemical thematic maps prepared for some elements and the other information can be used as basic information for water resource development and will enable to create awareness to users and the general public about the condition in the area before the problems aggravate and cause significant hydrogeological and ecological change to this economically essential area. The method used focuses on existing data evaluation, field assessment, some on spot hydrogeological parameter measurement and group discussion, representative sample collection and laboratory analysis, and interpretation of data using GIS based and other software's, and other approaches and