A watershed assessment is required before any forest development plan is prepared for a community watershed. Assessments may also be requested jointly by a Ministry of Forests district manager and a designated environment official in watersheds that are determined to have significant sensitivity, significant downstream fisheries values, or licensed domestic water users. A district manager can also require a watershed assessment for any situations in which he or she deems it to be necessary.
The Watershed Assessment Procedure (WAP) is an analytical procedure to help forest managers understand the type and extent of current water-related problems that may exist in a watershed, and to recognize the possible hydrological implications of proposed forestry-related development or restoration in that watershed.
The WAP considers the cumulative effects of forest practices on the aquatic environment. The assessment of hydrological impacts focuses on: 1) the potential for changes to peak streamflows; 2) the potential for accelerated landslide activity; 3) the potential for accelerated surface erosion; 4) channel bank erosion and changes to channel morphology as a result of logging the riparian vegetation; 5) the potential for change to the stream channel; and 6) the interaction of all of these processes, an evaluation of which indicates the sensitivity of the watershed to further forest development. The assessment also draws attention to natural processes occurring in the watershed. Using the results of a WAP, forest managers can make recommendations to prevent or mitigate the impacts of forestry-related activities in the watershed. Results can also be used to guide watershed restoration activities.
To accommodate the hydrological differences that exist between the coast and the interior of the province, the WAP differs slightly in some of its components. These differences are indicated in text by "CWAP" (Coastal Watershed Assessment Procedure) and "IWAP" (Interior Watershed Assessment Procedure).
This guidebook is intended to provide direction to all professionals - hydrologists - required to conduct watershed assessments. It is assumed that the individual conducting the assessment will use his or her professional judgment and experience in selecting methods best suited to the specific goals of the assessment and the characteristics of the specific watersheds and clients. It is also assumed that he or she will use judgment to determine how to incorporate non-forestry land uses, such as cattle ranging, recreation or mining, into the assessment.
BC Forest Service - Research Division. 1999. Coastal watershed assessment procedure guidebook (CWAP); Interior watershed assessment procedure guidebook (IWAP). 2nd ed., Ver. 2.1. British Columbia Ministry of Forests, Lands, Natural Resource Operations and Rural Development
Topic: FLNRORD Research Program
Keywords: watershed, assessment
To copy the URL of a document, Right Click on the document title, select "Copy Shortcut/Copy Link", then paste as needed. Only documents available to the public have this feature enabled.