Semarang City, Makassar City, and Ambon City are the pilot cities of the implementation of the Clean Cities, Blue Ocean (CCBO) project. Partnering with local partners and international experts, CCBO is implementing and testing relevant and sustainable local approaches to reduce plastic waste that drifts into the sea. Semarang City is one of its focus due to several factors, including (1) the lack of significant action in improving waste management; (2) the implementation of waste sorting still needs to be improved; and (3) the neglect of waste processing facilities