SECTION 2
Project and Watershed Description
CHARACTERIZATION of the WATERSHED
The Tsolum River is a low gradient stream that flows parallel to the coastal
plain of Vancouver Island for approximately 30 km from its headwaters near
Mt. Washington to the lower Comox Valley where it joins the Puntledge River.
The river is unusual, as it does not have any impassible barriers on its
mainstem. This 258 km2 watershed is fed by several small lakes, and supported
historical runs of pink, coho and steelhead and cutthroat trout which have
steadily declined since the late 1950’s. Some of the fish populations
are now near extinction levels despite intensive enhancement efforts to
raise coho and pink salmon at the DFO Tsolum River Facility.
There are six major, and dozens of minor, tributaries to the Tsolum
River. The main tributaries in the lower watershed are Portuguese Creek,
Dove Creek, and Headquarters Creek. Murex Creek, McKay Creek and Pyrrhotite
Creeks are located in the upper watershed, draining the abandoned open
pit copper mine previously operated by Mt. Washington Copper Co. (see Appendix
A).
LAND USE in the TSOLUM RIVER WATERSHED
The Tsolum River watershed is influenced by urban development, agriculture,
logging, and the abandoned mine. Residential and agricultural development
is in the lower watershed, mainly downstream from Headquarters Creek. Pasture
for dairy and beef cattle border portions of the lower Tsolum River. Second
pass forest harvesting occurs in the upper reaches of the watershed. An
extensive portion of the upper watershed is owned by TimberWest Forest
Limited, a forest harvesting and manufacturing company. Comox First Nation’s
Indian Reserve (IR) # 2 is located at the Tsolum River confluence with
the Puntledge River.
The project identified five main land use regions within the watershed
as shown in Appendix A. They include lowland agricultural, rural residential,
suburban residential, forested upper slopes and the upper watershed and
wetlands.
1) Lowland agricultural
This region extends from the confluence of the Tsolum and Puntledge Rivers
to the confluence of the Tsolum River with Dove Creek. Land use in the
region is predominantly agricultural. The area surrounding Lower Portuguese
Creek and Dove Creek is also included in this classification.
The Tsolum River watershed has been a major centre of agricultural activity
since the 1870s when settlers began developing farms in this region. Agriculture
is a major economic activity in the Comox Valley and many farmers are very
supportive of fish habitat restoration efforts. Most of this land is in
large parcels, which simplifies landowner contact. In many areas the lack
of riparian vegetation along the streambanks causes streambank instability
and erosion.
Main issues that were addressed by the TRTF in this region included
streambank erosion; lack of riparian vegetation; limiting cattle moving
across streambeds; improving fish habitat in drainage ditches; and water
use for irrigation and domestic purposes.
2) Rural residential
This area includes the Tsolum River mainstem from Dove Creek to the Tsolum
River Oxbow. This is also the predominant land use along the upper reaches
of Portuguese and Dove Creeks, as well as lower Headquarters Creek.
Land parcels in this area are smaller than the agricultural lowlands,
generally several acres per parcel. There is less land clearing and more
riparian vegetation. The increased number of properties in this area required
that more time be devoted to landowner contact in order to gain permission
to access this area for mapping and restoration work.
In this region, the TRTF concentrated upon increasing landowner awareness
of how upstream activities affects salmon habitat; on the lack of refuge
habitat and improvement of water quality in existing refuge ponds; on low
summer flows and lack of summer rearing habitat in tributaries; on the
importance of protecting wetlands from development and also conducted mapping
and fish habitat assessment in small streams.
3) Suburban residential
In upper Findlay Creek there are many suburban residential lots under 1
acre. Fish habitat and mapping studies are more labour intensive because
of the increased effort needed to contact every landowner bordering streams
in this area before data collection begins. Development pressure is high,
and use of water and chemicals to maintain lawns and gardens as well as
run off from paved surfaces impact the small streams in this area.
Main issues addressed in this region include landowner awareness of
how upstream activities affects salmon habitat; increasing developers’
awareness of the importance of wetlands and “ditch” habitat; and conducting
fish habitat assessment to locate areas of critical spawning and rearing
habitat. In addition, fish safe yard care methods should be publicized.
This should include information on reducing water use, maintaining riparian
vegetation, and limiting the use of chemical garden and lawn fertilizers.
A further need was identified for a campaign to raise landowner awareness
of how paving changes the hydrology of a watershed, as well as mapping
paved surfaces in this region of the watershed.
4) Forested upper slopes
The gradient is steeper here and forestry is the predominant land use.
TimberWest Ltd. is the largest landowner in the forested upper slopes.
Wolf Lake is an important reservoir in this area that supplies water to
the lower Tsolum River during times of low flow.
The forest companies control access of volunteers and TRTF personnel
in this area. In areas where active logging is occurring, access may be
dangerous, and radio contact is necessary to assure crew safety. Keys are
needed to access roads closed by locked gates.
The Vancouver Island Highway project is also impacting fisheries resources
in this region. A community based Siltwatch program has begun to monitor
stream siltation.
Main Issues addressed by TRTF in this region include obtaining landowner
permission for access to these lands; maintenance of riparian zones which
protect fish habitat; and effects of highway construction which may change
drainage patterns and cause siltation and streambank erosion.
5) Upper watershed and wetlands
This area includes the many lakes and wetlands which are important to maintaining
water flow and water quality. It also includes several higher gradient
tributaries to the Tsolum River as well as the mine site.
Protection of humic acid rich wetlands is crucial to reducing copper
toxicity in the Tsolum River. Draining or development of these areas would
reduce the watershed’s natural ability to detoxify copper contamination,
and would lower the acceptable dissolved copper concentration necessary
for fish health. Access to this area of the watershed is difficult due
to active logging and snow which covers the mine site and upper watershed
from November to June. During this time access is only possible by air,
or snowmobile. During other times of the year, a four-wheel drive is preferred
for travel off of the main logging roads.
In this part of the watershed, the TRTF addressed several concerns including
the copper leaching from the abandoned Mt. Washington mine site. Presently
levels of dissolved copper are above recommended water quality objectives
and must be reduced to less than seven parts per billion to maintain fish
health. There is no electricity at the mine site which necessitates the
use of battery powered monitoring equipment.
The TRTF also identified a need for a wetlands survey to be completed
with water quality testing completed to determine where reservoirs of humic
acid rich water are located. A culvert mapping and assessment survey should
also be completed to determine if culverts in this area are a barrier to
fish passage.
WATER USE in the TSOLUM RIVER WATERSHED
The Tsolum River is a source of water for domestic and agricultural use.
There are 14 registered domestic and 24 irrigation licenses on the Tsolum
River. Water flows are very low between July and October. Low water flows
and water temperatures in excess of 20oC during this time of year have
been cited as being one of the major factors contributing to the decline
of pink salmon populations.
SECTION 2--APPENDIX A
Tsolum Watershed Land Use Map
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