back to landscape team notes

 

 

Blue River Landscape Study Team

Aquatic Team Notes - 12/17/99

Present: John P., Dave K., Ray R., John C.

1. Sediment and large wood source area proposal

We reviewed the notes from our last meeting and the revised map John P. presented. We made the following agreements:

- accept John P.'s revised map as the map of S/LW source areas as amended during the meeting, and we will add data to GIS so these blocks can be plotted

- John P. will document the rationale and criteria used to map the S/LW source areas

- we will add language to the spatial pattern of retention trees to indicate that potential source areas of sediment and large wood to streams will be important areas to leave clumps and retention trees

- in addition, mapped sediment and large wood source areas in landscape areas two and three will have additional prescriptions:

             in Tidbits, Cook and Quentin subdrainages specific slope elements within mapped areas that meet the criteria identified in John P.'s documentation will have the same prescription as landscape area one; these are areas of shallow soils on steep (>70%) slope;

            in Mann and Wolf subdrainages there will be a no-cut buffer of one tree height where perennial streams are adjacent to earthflows, and one half to one tree height where intermittent streams are adjacent to earthflows; these are areas of extensive earthflow soils

2. High-value aquatic habitat reaches

- Dave will work with Tere to get his mapped reaches into GIS so we can plot them

- Dave and Ray will document the rationale and criteria for mapping aquatic habitat reaches

3. Water and nutrient source areas

We reviewed the summer baseflow and wetland maps to identify blocks for particular water quality and quantity emphasis. We looked for areas of substantial summer baseflow and areas with substantial wetlands. We made the following agreements:

- we accepted Dave's map as amended during the meeting and we will add data to GIS so these blocks can be plotted

- Dave will document the rationale and criteria used to map the water quality source areas

- additional prescriptions will be applied in these water quality source areas as follows:

            all perennial streams with a significant flow will have a one tree height buffer where at least 70% canopy cover will be retained on the south side of east-west flowing streams, and a one half tree height buffer where at least 70% canopy cover will be retained on both sides of north-south flowing streams in the mapped baseflow areas

            no road construction, ground skidding or other activity that potentially affects surface and subsurface water flow paths should be permitted in wetlands

4. Road restoration

We reviewed the road rankings produced by the watershed process equations we developed at our last meeting, and discussed alternative ways to summarize rankings including weighting the mass movement sum more heavily, using the fine sediment and hydrologic effects rankings more heavily for maintenance priorities. We will develop a couple more variations of aquatic summary rankings.

We discussed a couple of ways to display the logic process for making decisions as a hierarchical key; e.g.,

on system         keep                 high maintenance priority

                                                medium maintenance priority

                                                low maintenance priority

                        store                 high priority for action

                                                medium priority for action

                                                low priority for action

off system         high priority for action

                        medium priority for action

                        low priority for action

 

We also developed a subdrainage rating system:

Subdrainage    Dominant terrain/ranking       RoS      Stream/road density Priority

Mann               earthflow          low                   medium            1                      medium

Wolf                 glacial               medium            medium            3                      medium

Quentin            dissected          high                  high                  4                      high

Cook               dissected          high                  high                  5                      high

Tidbits/Ore       dissected          high                  high                  6                      high

Quartz+            dissected          medium            medium            7                      low

BR Face           glacial               low                   medium            2                      medium

BR Reservoir    dissected          low                   low                   8                      low

We will generate the GIS overlays to validate this ranking with data. Subdrainage rankings will then be used to establish overall priorities for restoration activities.