Penilaian Kerusakan dan Model Pengelolaan Hulu Daerah Aliran Sungai Deli Provinsi Sumatera Utara

Abstract

The Deli Watershed (DAS) is designated as a watershed whose carrying capacity needs to be restored based on the Decree of the Minister of Forestry of the Republic of Indonesia Number: SK. 328/Menhut-II/2009 concerning Determination of Priority Watersheds in the Framework of Medium-Term Development 2010-2014. This status is supported by watershed conditions prone to environmental damage, such as erosion, landslides, floods, droughts, and critical land and sedimentation. One of the reasons the status of the Deli Watershed has not changed since it was first established is the lack of green vegetation (forest) in the Deli Watershed, which is only 2,610.96 ha (6.68%) of the total watershed area. Meanwhile, the forest area ideally is 30% of the entire watershed area as regulated in the Law of the Republic of Indonesia Number 41 of 1999 concerning Forestry. The environmental degradation in the Deli Watershed is determined by the condition of its upstream, which functions as a conservation area. Good environmental conditions do not support the function of the upstream Deli Watershed as a water regulator, so this area is experiencing various problems, including soil erosion/slides, critical land, and decreased soil nutrient content. These environmental problems result in economic losses for the community as resource users and the government as policymakers. Based on this explanation, this study aimed to 1) identify the factors causing the damage to the upstream Deli Watershed; 2) estimate the value of the economic loss from the damage to the upstream Deli Watershed; and 3) analyze the institutional management of the upstream Deli Watershed. The methods used in this research were Root Cause Analysis (RCA), Geographic Information System (GIS), Universal Soil Loss Equation (USLE), replacement cost, content analysis, and actor analysis using primary and secondary data. The results of the root cause analysis stated that limited ownership of the land area, business capital, and skills of farmers was the core problems of environmental damage in the upstream Deli Watershed. The solution is by developing additional income/livelihood of the community through guidance and counseling by relevant government and local government agencies. The calculation of economic losses due to damage to soil fertility in the upstream Deli Watershed was IDR 2,179,828,456/ha/year. This nominal represents the replacement cost of soil macronutrients (N, P, K) lost due to 267.93 tons/ha/year erosion on Ultisol soil types. This calculation used the nutrient content of chicken manure as a substitute for the lost soil nutrient content. The institutional analysis of the upstream Deli Watershed management consists of a content analysis of statutory regulations and an actor analysis involving five groups of formal actors (central government, provincial government, district government, non-structural institutions, and resource users). The existing regulations have been implemented according to their substance by the managing actors. However, environmental degradation still occurs due to the ineffective performance of actors in managing the upstream Deli Watershed. Institutions with a working area covering the upstream Deli Watershed have not been actively involved in preparing the Deli Watershed management plan. Furthermore, the institution as a coordination forum has not been able to oversee all stakeholders managing the Deli Watershed. Therefore, the role, capacity, and coordination of managing actors, both cross-administrative and cross-sectoral, need to be improved to achieve the expected management objectives following the laws and regulations.