Building with Nature and reuse of dredged materials in the Colombian context Building with nature – The beneficial use of dredged materials in the Colombian contextIntroductionSeveral master plans have been developed for various water management topics under the Delta cooperation between the governments of Colombia and the Netherlands since 2017. Colombia's National Development Plan 2018 - 2022 highlighted the opportunity for beneficial use of dredged materials for multiple needs of the country's coasts, recommending:•	Change the conception about the disposal of dredged material offshore and recognize it as a valuable resource to be used, both in water and on land;•	Adapt or develop legislation favorable to the use of dredged material;•	Develop methodologies to evaluate the benefit to society of using dredged material instead of discarding it.•	Develop mechanisms to articulate supply and demand for dredged material.Based on these recommendations and the topics addressed in previous webinars, it was suggested to conduct a study on the beneficial use of dredged materials with the concept of Building with Nature in the Colombian context. The project focuses on this topic through the following four activities:Activity 1: Opportunities to expand the range of beneficial uses of dredged materialFor this activity, a methodology was developed to identify the function (type of use) appropriate for the Colombian context, whereby the dredging activities (supply) and local challenges (demand) determine the potential application of dredged material, in conjunction with the type of landscape and ecological characteristics present. This methodology provides ample room to include and embed Building with Nature approaches in potential uses of dredged material. Throughout the study, five port areas were analyzed in more detail to identify opportunities to expand the range of beneficial uses of dredged material: ZP 9: Tumaco, ZP 8: Buenaventura, ZP 5: Cartagena, ZP 4: Barranquilla, and ZP 1: San Andres.The beneficial uses of dredged material are wide-ranging, and Colombia's opportunities vary depending on the specific dredging location. In terms of social equity, the economic benefits generated by the beneficial use of dredged material depend on how the labor force is incorporated and how these initiatives are conducted. Uses of dredged sediments related to the restoration of wetlands and the reinforcement of the natural defense systems of the coastline are significant as they contribute to the improvement of ecosystem services that have a positive impact on the social conditions of humans and the environment. Activity 2: Case studies and examples of legal frameworks and regulatory requirementsDuring the study, Colombia’s legal system was compared to the legal frameworks of the Netherlands, the United States of America, and Panama. This comparison was conducted to analyze how Colombia can facilitate and stimulate the beneficial use of dredged material. Several conclusions can be drawn based on the comparative analysis, such as: •	There is no legal framework that can simply be transferred to Colombia. Each country has its cultural context and corresponding legal framework.•	In most legal frameworks compared, the beneficial use of dredged material (non-polluted) is prioritized and encouraged.•	The philosophy that accompanies the legal frameworks of countries that do not require a specific permit for the beneficial use of dredged material is simplicity and ease for the project operator or executor, as it seeks to encourage beneficial use, avoiding making it an additional and disproportionate burden for the project operator or executor. •	It is not common in comparative legal regimes that the beneficial use of dredged material is included in the environmental impact studies of the main activity that generates it, i.e., dredging. Activity 3: Buenaventura Case StudyOf the five port areas identified, Buenaventura was analyzed as a case study based on the following aspects: the natural system, the socio-economic circumstances, and the dredged material's characteristics. The analysis has provided four (4) options for the beneficial use of dredged material in the outer bay and two (2) options for dredged material from the inner bay, compared to the reference option (dispose of in the sea). Two workshops were held with stakeholders and project counterparts to discuss their views and considerations regarding the development and implementation of the proposed solution(s). It is important to highlight that any future process of selection and/or development of one or more of the proposed options must consider the human rights context in Colombia and the historical events in Buenaventura, specifically the allegations made about the human rights violations in the Estero de San Antonio. Currently a precautionary measure of December 2021 by the Special Jurisdiction for Peace (JEP) prohibits any intervention of dredging and civil works on the Estero de San Antonio for 180 days. Any potential intervention to promote the use of dredged material in the municipality of Buenaventura must respect the reconciliation and peace process that the Buenaventura community is going through, as well as the provisions of the jurisdiction for peace - JEP.Activity 4: Barriers and enablers to the beneficial use of dredged materialBeneficial use of dredged material, building with nature, and solutions based on such concepts are dynamic and innovative ideas that can be harnessed to meet societal needs, whether economic, ecological, and/or social. However, these concepts require a thorough understanding of the natural and socio-economic system to contextualize the solution appropriately. The main barriers can be summarized to: 1. finding adequate solutions, 2. pollution, 3. costs, 4. inequitable benefits, 5. negative perception, and 6. complex or non-existent legal system. However, there are also enablers for these barriers that can facilitate and propel the beneficial use of dredged material in alignment with local needs and Building with Nature. Facilitators for this process can be: 1. connecting the demand and supply of dredged material, 2. assessing the physical and chemical composition within legal boundaries, 3. non-monetary values or environmental compensation, 4. stakeholder consultation, 5. contribution to a broader development plan, 6. connecting to the stakeholders, 7. revising the legal norms, and 8. adjusting the Terms of References in dredging contracts.