Water Stewardship Information Sources
| Citation | Wright, HM. 2003. Stream flow, water quality, and low-level nutrient monitoring in the Englishman River Watershed, 2002. Prepared for Pacific Salmon Foundation. |
|---|---|
| Organization | Pacific Salmon Foundation |
| URL | http://www.bccf.com/steelhead/pdf/eman%20_flow_and_wq_2003.pdf |
| Abstract/Description or Keywords | Following initial habitat assessments and literature reviews, the Pacific Salmon Foundation identified further flow and water quality monitoring as a priority under the Englishman River Watershed Recovery Plan. In 2002, Lough and Morley determined reduced summer flow was limiting to fish production and northwest hydraulic consultants identified potential loss of Englishman River surface water through groundwater seepage. Discharge was monitored in the mainstem and Morison Creek with semi-permanent stage recorders and flow metering. Fish habitat suitability was measured as discharge decreased through the low water period by conducting depth/velocity transects, measuring wetted width, and photographing habitat. Results confirmed mainstem discharge dropped below the minimum threshold of the current Provisional Operation Rule for Arrowsmith Dam fisheries flow releases. Loss of flow by groundwater seepage appeared insignificant, but results were inconsistent. Habitat suitability monitoring reconfirmed ideal base summer flow would be near 20% of mean annual discharge, or 2.76 m3 /s. The current minimum base flow is 1.6 m3 /s, or approximately 10% of mean annual discharge. Hydrometric data for Morison Creek identified a rapid decrease in flow in early August, possibly a result of rural or agricultural withdrawals. Water samples collected from the mainstem indicated lack of inorganic nutrients may be limiting to fish production. Harmful bacteria and metals were present only in very low concentrations and were not considered a risk to salmonid fish species. Recommendations resulting from this study are as follows: 1. Reassess mainstem discharge to confirm potential loss of flow by groundwater seepage. 2. Determine the cause of water loss in Morison Creek. 3. Maintain summer flow near 20% of mean annual discharge (2.76 m3 /s), with a short term minimum base flow of 10% (1.38 m3 /s). 4. Initiate stream enrichment in the mainstem to increase primary autotrophic productivity. |
| Information Type | report |
| Regional Watershed | Vancouver Island South |
| Sub-watershed if known | Englishman River |
| Aquifer # | |
| Comments | |
| Project status | complete |
| Contact Name | |
| Contact Email |