Impact of land use/land cover changes on ecosystem service values in the cherangany hills water tower, Kenya

•Cropland, water bodies, and built-up areas increased whereas forest, grassland, and bareland areas decreased.•Huge conversions of grassland and forestland to cropland negatively affected the provision of ecosystem services.•An estimated loss of 8.68 million USD in total ESV within the past 37 years in the Cherangani Hills Water Tower.•Estimates of the individual and total ESV changes are significant for policy formulation and decision making.