Transcript Rideau lakes Watershed,What We Know

Rideau Lakes
Watershed Plan 2005
The Rideau Lakes Watershed
 Is
50 km long
 Covers an area of 490 km2
 Has 25 lakes (127 km2 )
 3 communities – Westport, Newboro,
Portland, 5 municipalities and 3 counties
 Has its headwaters at Long Pond Lake
 Outlets at Poonamalie Dam
 Has one major tributary – the Tay River
Hydrology
 Watershed
has 5 dams: Wolfe Lake,
Westport Sand, Westport, Narrows and
Poonamalie
 Water levels fluctuate 1.0m
 Water level data collected at Wolfe, Big
and Lower Rideau
 No flow data collected
 No estimate of water budget
Spill Zone
Upper Conservation Level
Series3
Rule Curve
Series5
Low er Conservation Level
2004 Water Levels
2005 Water Levels
Historic Average
UPPER RIDEAU LAKE
Operating Rule Curve 2001
125.0
124.8
ELEVATION (m)
124.6
124.4
124.2
124.0
123.8
123.6
123.4
123.2
123.0
Jan
Feb Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov Dec
Hydrology (cont’d)
 RVCA will
be undertaking numerical
modeling in the future to determine the
impacts of land use, dam operations,
breaches, etc.
Fish and Wildlife
 Limited
data available for fish
 Many fish inventories done in early 70’s,
little since in smaller lakes
 Upper Rideau netting surveys in 2002
indicate decreases in N. Pike, Sm Bass,
Yellow Perch and Walleye communities
 Walleye #’s extremely low due to loss of
habitat, water quality, introduction of
invasive species, over-fishing
Fish and Wildlife (cont’d)
 Big
Rideau Lake is a Class 1 fishery (cold
and warm water, good for sport fishing)
 9 species stocked in 130 years
 Netting in late 90’s reveals mostly N. Pike
and Y. Perch, very few Trout, very few
Walleye
 Presently collecting benthic data for water
quality
Fish and Wildlife (cont’d)
2
Commercial Fishing licenses in
watershed
 License is for panfish e.g. bluegill, rock
bass
 MNR reports healthy, diverse panfish
fishery and will continue to support
commercial fishery license. MNR will
monitor fishery and operation of fishermen
Fish and Wildlife (cont’d)
 31
species at risk in watershed
 7 invasive species recorded
 4 Areas of Natural and Scientific Interest
 10 Provincially Significant wetlands
 No information on shoreline health
 1673 different species of plants, animals,
fish, birds, etc.
 No analysis of old growth forest
Rideau Lakes Watershed
Land Cover
Aggregated Class
Wetland
Area
(ha)
Area (%)
2865
6
Forest, Woodland
22999
51
Water
11902
26
7220
16
44988
100
Cropland, Pasture,
Abandoned Land
Watershed total
Groundwater
 Very
little is known about groundwater
quality or quantity on a watershed basis
 Westport has 2 municipal wells of good
supply and quality
 Groundwater studies have been done on a
regional scale and provide little to
watershed level study
 No known water quality or quantity
problems
Groundwater (cont’d)
 Most
domestic water comes from
Precambrian bedrock
 Overburden is thin therefore aquifers are
vulnerable to contamination from surface
(i.e. linked to land use)
 Extraction has increased recently (last 40
years) due to shoreline development
Land Use
 Area
settled in late 1700’s. Land use
primarily agriculture and logging. By 1870
the area was completely logged
 Canal built 1826-1832
 Area used for recreation since late 1890’s
 Most cottage development since WWII
 Now development pressure is in cottage
conversions to permanent homes
Land Use (cont’d)
 Environmental
stressors associated with
over-use, smaller lots, denuded lots,
shoreline erosion, poor land management
practices
 Population (in 3 counties) expected to
increase 20% over next 25 years
Land Use (cont’d)
 Some
municipalities have a higher
seasonal than permanent population
 Only Westport on municipal water and
sewer. Rest of watershed is private wells,
lake and septics
 Westport has snowfluent system (1995)–
removes 100% of nutrients and bacteria
 No direct discharge to lake
Land Use (cont’d)
 The
aesthetics to URL improved
 Operation is in compliance with MoE
regulations. Health risks eliminated
 Watershed governed by mix of federal,
provincial, municipal and county agencies
 5 municipalities govern development in
watershed. OP policies inconsistent
Land Use (cont’d)
 Mineral
Rights: mining companies have
right to lay claim on properties without
owners knowledge/permission
 Prospectors can excavate 1000 tonnes of
materials with 24 hours notice and surface
strip within 100m of waterbody
Tourism and Recreation
 Is
a major recreation/tourism destination in
Eastern Ontario
 Rideau watershed caters to day trippers
 Watershed home to marinas,
campgrounds, trailer parks, conservation
areas, provincial park, festivals, art shows,
fishing tournaments, golf courses, trails,
etc.
Tourism and Recreation (cont’d)
 Lanark:
50% of tax base is tourism,
generating $63M per year
 Future
tourism pressures expected as
Canal celebrates 175th birthday and
becomes UNESCO site in 2007
Surface Water Quality
 Of
the 25 lakes, no data on 14, very little
on 5, enough on 6 to make an assessment
 Data inconsistent in frequency, parameter
and quality therefore difficult to determine
trends/general statements
 Data collected for TP, TKN, chlor a and
clarity (secchi disk)
 Lakes mostly “middle-aged” with aquatic
vegetation filling in shallow areas
Water Quality (cont’d)
 Lakes
are affected by invasive species
such as zebra mussels, spiny water flea
 Tributaries (four major) are adding high
levels of nutrients
 Adrains Creek adding high levels of
nutrients, likely due to agricultural activity
and aluminum and iron
Water Quality (cont’d)
 Westport
Sand Lake, Upper and Big
Rideau Lakes seem to be improving in
clarity and levels of nutrients
 Lakes are generally healthy but need more
data/monitoring
 Need to investigate/monitor sources of
impairment
Summary and Conclusions
 Tourism
and Recreation is main economic
activity
 Watershed is a “managed” system
 Environmental stressors from the amount
of people living in and visiting watershed,
over-fishing, poor environmental practices
on behalf of dwellers and visitors
 As populations increase, stressors
increase
Summary and Conclusions (cont’d)
 Trend
toward cottage conversions can
have impacts on ecosystem health
 Water quality generally good
 More data/studies needed on almost all
aspects of watershed health to identify
level of health and trends over time