In some cases one may encounter weak stratum this prompts need for improving the ground if a structure is to be constructed, to make sure that safety of the structure and the stability of adjacent buildings. Improvement of ground can be done using several techniques, in particular granular soils like sandy soil can be improved using different techniques such as; Grouting, Vibro-compaction, Thermal treatment, Pre-compressing, Ground freezing, Soil nailing, Micro- piles and stone columns.

Over the past few decades, there has been an increase in global population. This increase has resulted into greater consumption of resources such as water, thus putting a strain on the water resources available for use on earth (Charania, Principles of Hydrology for Practising Engineers: Basic Hydrology, 2016).

Based on the latest United Nations estimates, as per October 21st 2018, the population of Kenya stands at 51.3 million. This shows an annual growth of around 2.5% every year. The approximate population of Nairobi is around 6.5 million in the metropolitan area and 3.5 million in the city proper as per 2009.The Ongata Rongai population has increased from 40178 in 2009 to approximately 66042 in 2018.The increasing population is due to the rapid urbanization.