The note in link put forward the concept of maintenance and the distinction that can be done between preventive or corrective maintenance and rehabilitation. It highlights notions of regular care and diagnosis for water systems in rural areas (not only for SIerra Leone !) for gravity schemes, wells and boreholes equipped of hand pumps).
www.interaide.org/pratiques/sites/default/files/definitions_of_the_maintenance_-_april_16_2013.pdf 
