Catchment Management in your city

Catchment management in your city

Many cities and municipalities globally are experiencing high levels of urbanization, which creates vibrant centers of social and technical innovation and economic opportunities and growth, but also places immense pressure on natural resources and their ability to provide benefits to people. Natural resources — and specifically urban water resources — are essential in providing water for drinking, household use, economic development, recreation, hydropower, in addition to supporting transporting and assimilating of waste, as well as biodiversity. However, these urban water resources typically become degraded unless local governments, civil society and businesses work together to promote their wise management and use.

Challenges that are typical of urban water systems include drought, flooding, fecal and solid waste pollution, aging water provision and waste treatment infrastructure, spatial and development planning that do not accommodate catchment goals or ecosystem limitations, degraded riparian open spaces and demand for settlement leading to encroachment into river courses. Catchment management planning — which facilitates collective action — is one approach to securing the wise use and management of urban water resources.

Globally, there is a paradigm shift towards ‘water sensitive cities’. This way of thinking incorporates stormwater as part of the available urban water resource and focuses municipal water planning to address multiple service delivery functions as well as complex sustainability challenges such as climate risks, quality of life and equity. Catchment management planning creates a platform for this integration of functions, involving stakeholders across many sectors and levels of governance.

What is Catchment Management?

What is a catchment?

A catchment can be described as an area of land surrounded by higher ground like hills and mountains, where water drains to the lowest point (e.g. a creek, river, lake or ocean). The catchment area includes all the land area that drains rainfall into rivers or streams (and some may flow underground) that flow out to the coast and may affect mangrove forests, seagrass beds and coral reefs. The term catchment is also used for the area of land that drains water into dams; or includes sedimentation basins.

A large catchment area is often made up of a number of smaller catchments called sub-catchments. A catchment can be as small as one or two houses or a small village or it could cover an area greater than 250,000 km2, like the Amazon basin. Because water flows downhill, any activities involving the use or management of natural resources in the upper catchment can affect the lower part of the catchment and the overall marine environment. Catchments can be affected by numerous factors including seasons - whether dry or rainy, topography, soil types, population density, forestry, development - such as industrial or mining activities, and farming practices. Consequently, there is a need to adopt a whole or integrated catchment approach to ensure that damaging activities such as pollution do not impact others — particularly downstream communities of the catchment.

Read more on IUCN

What is catchment management?

Catchment management can broadly be defined as the process of setting a vision, goals, indicators and measurable targets for change to achieve a healthy catchment area, and ensuring that there is an accompanying monitoring program in place. In addition, managing a catchment includes the coordination of stakeholders and their relationships, as they engage with the goals and actions that, collectively, should promote positive change as reflected in both the measured indicators and in the quality of catchment-related services for urban communities. There are numerous tools that support catchment management planning but there is no one size fits all and each municipality will define their objectives differently, depending on the local context and priorities. Thus, one urban catchment management plan might focus on local community river health initiatives while another might be more focused on improved stormwater management or the need for water security through groundwater recharge. The scale of a CMP can also vary, based on the scale at which action is effective, the scale most appropriate for hydrological modeling and/or the municipal boundary.

What is integrated catchment management?

As mentioned above, effective catchment management requires an integrated approach that considers the impacts on both upstream and downstream communities of a specific catchment.

ICM can be defined as a system-based approach, which aims to combine the objectives of environmental protection, sustainable agriculture, and natural resource management within catchments, with the principles of ecologically sustainable development. ICM acknowledges that because the flows and stocks of water, sediment and contaminants are usually contained within topographical boundaries, the river basin or catchment is the appropriate organizing unit for understanding and managing ecosystem processes in a context that includes social, economic and political considerations, and guides communities towards an agreed vision of sustainable natural resource management in their catchment. Accordingly, ICM comprises not just the outcome of sustainable levels of resource exploitation, but the ongoing process to achieve and improve sustainability.

Synonyms used in catchment management approaches

Watershed

Drainage basin

Urban rivers

Integrated river basin management

integrated water resource management (IWRM)

natural resource management (NRM)

What can you expect from this Guide?

This is a general guide to managing and carrying out Catchment Management Planning that can be applied globally, in alignment with the legislation of your national, subnational and local government. As noted above, the terminology used to define a ‘catchment’ varies in different geographical contexts, and that this guide specifically offers an approach to managing urban rivers (see Information Box for synonyms).

Our Catchment Management guide offers useful case studies and references, some of which describe available management techniques in a format that is easy to use and access, to provide resources to cities which should contribute to the restoration and conservation of freshwater ecosystems and safeguard their benefits to people. To be applicable anywhere in the world and enable its general use, this guide is deliberately broad.

(1) The guide first outlines the importance of developing a catchment management plan by initially defining and understanding the problem area. Baseline knowledge of an urban catchment is an essential prerequisite to efficient and suitable management efforts.

(2) Second, the guide provides suitable tools and resources to ensure the successful implementation of the catchment management plan.