Composted Sewage Sludge as Soil Amendment in Colombia: Challenges and Opportunities to Scale Up

Abstract

Composted Sewage Sludge is a rich material that can improve the soil's physical and chemical properties when it meets the corresponding national regulations and follows specific soil and crop needs. This review explores composted sewage sludge (SS) as a soil amendment in Colombia, focusing on its challenges and opportunities for scaling up. Sewage sludge, a by-product of wastewater treatment, is rich in organic matter and essential nutrients but requires proper treatment due to potential contaminants. Compositing SS presents an effective method for transforming this waste into a valuable soil amendment, improving soil fertility, water retention, and organic content. Despite its benefits, SS composting faces hurdles in Colombia, including limited regulatory support and underdeveloped applications. Colombian regulations, such as Decree 1287 of 2014 and CONPES 4004, provide bases for SS usage but lack updates on emerging contaminants or specific goals for SS deployment. This review identifies a gap in documented experiments and industrial applications within Colombia and highlights the need for enhanced regulatory diffusion and updated standards. It also emphasizes the importance of promoting financial incentives for SS composting projects. The review concludes that while composted SS offers significant environmental and economic benefits, including soil restoration and reduced chemical fertilizer use, realizing its full potential requires addressing regulatory, financial, and research challenges.