’s Country Lakes

Long-term Trends in Water Quality from the Lake Partner Program

Anna DeSellas and Andrew Paterson Dorset Environmental Science Centre, MOECC

November 22, 2017 1 Latornell Conservation Symposium Inland lakes in Ontario

• 200,000+ lakes • majority on Precambrian (Canadian) Shield • soft-water, acidic, nutrient-poor • water quality is generally good

25.0 n=1994 20.0

15.0

10.0

5.0 Percent of lakes sampled lakes of Percent Canadian Shield 0.0 0-2 2-4 4-6 6-8 >30 8-10 10-12 12-14 14-16 16-18 18-20 20-22 22-24 24-26 26-28 28-30

Total Phosphorus (ug·L-1)

2 Why is Water Quality Important to People?

• One of the most important concerns of waterfront property owners

• Makes for a more enjoyable lake experience – swimming, boating, and other recreational activities

3 The economic value of clean water in Ontario

• ~2 million adult anglers per year

− $1.2 billion in fishing gear, boats, etc.

− $1.7 billion in activities related to fishing Photo: Gregory Brand

• $1 billion annually on recreational boating

• commercial fisheries (~$42.5 million)

• water-related tourism (~$5.5 billion)

(Source: Lakeshore Capacity Assessment Handbook- May 2010) 4 Prices rise by ~6% for every metre increase in water clarity

5 Environmental stressors Acid deposition

Climate change Contaminants

Inland Lakes

Invasive species Emerging issues

Land-use Photo: Gregory Brand change

6 (Smol, 2008. Pollution of Lakes and Rivers) 7 CITIZEN SCIENCE

Adapted from: Smol, 2008. Pollution of Lakes and Rivers 8 Lake Partner Program

Mission:

• To foster interest and educate citizens on water quality issues affecting in inland lakes in Ontario

• To promote stewardship of lake ecosystem health in Ontario

• In partnership with Ontarians, to create and maintain a province- wide, long-term database on water quality for Ontario’s inland lakes

9 Lake Partner Program

• Each year, > 600 volunteers monitor water quality and water clarity in 550 lakes at over 800 locations

• Volunteers send water samples to DESC chemistry lab for analyses

• Data are updated and shared annually online

• Data used to assess and report on water quality across Ontario

Largest volunteer-based water quality monitoring program of its kind in

10 An emphasis on “Partner”

Through partnership, the LPP…

• Collects more samples, more frequently at more locations across Ontario

• Enhances knowledge and education through stewardship

• The Federation of Ontario Cottagers’ Associations (FOCA) helps to recruit LPP volunteers, disseminates information, and trains and educates volunteers

More effectively monitor & protect the health of Ontario’s water resources

11 What we measure, and why

Total Phosphorus Water clarity Calcium Chloride (TP) (since 2008) (since 2015)

• Important nutrient • Estimated using a • Essential element • There have been controlling the growth Secchi Disk that is required by increases in of algae in Ontario all living organisms chloride Lakes concentrations across the province due to road salt

12 Total Phosphorus

13 Total Phosphorus

Algal abundance These water quality parameters: (phytoplankton, Chl-a) - are difficult or expensive to measure Transparency (Secchi disc depth) - cannot be managed directly Hypolimnetic dissolved O2

Total phosphorus [TP] the most reliable indicator of trophic status

Photo: Kathryn Hargan

14 Total Phosphorus – Current status

In Ontario, the Provincial Water Quality Objective (PWQO) for total phosphorus in inland lakes is < 20 µg/L to:

“avoid nuisance concentrations of algae in lakes”

15 Total Phosphorus – Current status

• 93% of inland lakes in the Lake Partner Program meet the PWQO objective

16 Total Phosphorus – Change over time?

• At a landscape scale, TP concentrations have not changed significantly over the last ~ten years

17 Calcium (Ca) – Long-term declines in recent decades

• Ca levels have been declining in Ontario inland lakes

) • Main causes are historical acid -1 3.5 deposition (acid rain) and biomass loss through timber 3.0 harvesting 2.5

• Recent laboratory and field experiments have shown that 2.0 when Ca levels fall below 1.5-2 mg/L, aquatic organisms may be 1.5 negatively affected

CalciumConcentration (mg·L • The LPP has been monitoring 1.0 Ca since 2008 1975 1980 1985 1990 1995 2000 Year

18 Ca is required by all living organisms

• Ca is a nutrient required by all living organisms to varying degrees

• some organisms are very sensitive to declining Ca levels

• e.g., Daphnia (zooplankton) - Ca is used to regenerate their carapaces when they moult

19 Calcium – Current status

• The majority of LPP lakes in Ontario have Ca levels that can support calcium-rich aquatic organisms

• But, ~15% of lakes are at Ca concentrations that may hinder the reproduction and survival of some Ca-rich organisms (< 2.0 mg/L)

20 Calcium – Change over time?

• Lakes are continuing to show declines in Ca concentrations

• (based on a comparison of 2008 and 2016 data from the LPP) 2016 [Ca] 2016 [Ca] (mg/L)

2008 [Ca] (mg/L)

21 Water clarity

• measured using a Secchi Disk

• invented by Angelo Secchi in 1865, and modified for use in lakes by George C. Whipple in 1899

Secchi transparency depth is influenced by:

- turbidity

- algal biomass

- colour of the water (influenced by dissolved organic matter)

22 Water clarity – Current status

23 Water clarity – Change over time (2000-2014)?

70 • Most lakes show no significant change in Secchi from 2000- 60 2014 50

40 • ~21% of the lakes show a decline in water clarity over 30 Lakes (%) Lakes time

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10 • This could be due to long-term increases in dissolved organic 0 carbon (DOC) – lakes are No change Strong Weak Weak Strong becoming more tea-stained in decline decline increase increase appearance Long-term trend in Secchi transparency

24 Water clarity – Change over time?

25 Water clarity – Change over time?

26 Reporting on the data

Recent (2016) survey of volunteers showed a desire to learn more about how the LPP data are used…. • Report Card - 2016 – summary of current state of water quality (Ca, TP, Secchi) in 350-450 volunteer-monitored lakes across Ontario

• DESC student projects - 2016 (water clarity) & 2017 (calcium)

• Partnerships - 2016 project; Ryerson University, FOCA & MNRF; examined LPP phosphorus data & effects of landscape factors

• Story Map – communicate the message and data

www.desc.ca/programs/LPP

27 Acknowledgements

This program would not be possible without the involvement of:

• the many Volunteers and Lake Stewards • the Federation of Ontario Cottagers’ Associations (FOCA) • MOECC Dorset Environmental Science Centre’s water chemistry laboratory • other DESC staff, including Partner staff • The of Muskoka • Michelle Palmer, Claire Holeton, Kaoru Utsumi (MOECC Algae Lab) • MOECC’s Laboratory Services Branch & Operations Division

28 29 Other resources

• Data mapping tool (www.ontario.ca/environment-and- energy/map-lake-partner)

• Data (www.ontario.ca/data/ontario-lake- partner)

• Dorset Environmental Science Centre (www.desc.ca)

• Federation of Ontario Cottagers’ Associations (www.foca.on.ca)

• Toll-free Hotline: 1-800-470-8322; email: [email protected]

• Spills Action Centre (if you suspect a blue-green algal bloom): 1-800-268-6060

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