Many rivers, lakes and other inland waters have been modified and degraded by human activities. Rehabilitation of degraded systems and mitigation of impacts of ongoing stresses are needed to preserve ecosystem services and fisheries and are of a high priority if the aquatic biodiversity of inland waters is to be conserved. A number of technical solutions for rehabilitation and mitigation are available to restore habitat diversity, provide for environmental flows and ensure longitudinal and lateral connectivity within such systems. It is recommended that such methods are applied on a basin-wide scale but it is recognized that more restricted sections of waterbodies may have to be targeted. Planning for rehabilitation projects needs to be carefully conceived with clear objectives of the rehabilitation and selection methods to be used. Selecting appropriate methods for any particular waterbody depends on local, social and economic conditions and priorities. Land tenure, local laws and the interests of other local stakeholders in the resource also need to be incorporated into rehabilitation plans.
In international rivers and lakes, rehabilitation plans may need negotiation and cooperation by all riparian states. After execution, rehabilitation projects should be carefully monitored in order to meet the objectives.