Water Urbanism and Land Use Change: A Conservation Strategy for Nanyuki Riverine Ecosystem, Laikipia County

Abstract

Urban riverine ecosystems are increasingly threatened by rapid land use transformations driven by urbanization, agricultural expansion, and infrastructure development in the Global South. This study develops a conservation strategy for the Nanyuki River by examining the effects of land use change on hydrology, water quality, and biodiversity within a water urbanism framework. A mixed-methods approach integrating spatial analysis, field measurements, water quality assessment, biodiversity surveys, and stakeholder perspectives was employed. Findings reveal significant spatial variation along the river corridor. Upstream sections remained relatively stable, while urbanized midstream areas experienced reduced flows, biodiversity decline, and severe microbial contamination. Downstream sections exhibited cumulative pollution impacts associated with increased impervious surfaces, riparian encroachment, and wastewater discharge. The study demonstrates that land use intensity is a major driver of ecological degradation and reduced river health. It proposes a water urbanism conservation framework integrating land use planning, riparian protection, decentralized wastewater management, and community-based governance to support sustainable river restoration and adaptive urban water management.