Lake-Erie-algae-bloom
In October 2011, Lake Erie experienced one of the worst algal blooms in its history. Photo credit: NASA Earth Observatory.

If Ontario hopes to reverse current trends of harmful algal blooms, it needs a guiding principle around stormwater management to “monitor, quantify and report” how projects at every scale affect phosphorus levels, states a new report from the Environmental Commissioner of Ontario.

While municipal wastewater treatment plants have come a long way on phosphorus controls since the 1970s, runoff from rural, agricultural and urban land has become the new modern threat of raising phosphorus levels to the point where algal blooms can endanger drinking water and cause fish die-offs, states the October 2017 report, Good Choices, Bad Choices. As southern Ontario rapidly urbanizes, construction sites, for example, often add large loads of sediment and phosphorus to waterways, and places like Ontario’s 800-plus golf courses are left to weigh voluntary measures in the face of no phosphorus restrictions.

Meanwhile, Ontario is running several programs to ensure phosphorus reduction, yet isn’t measuring their efficacy, the report warns, adding that voluntary measures and unevaluated programs may need to be replaced with “muscles and metrics”.

Dianne Saxe, Environmental Commissioner of Ontario. Photo credit: Environmental Commissioner of Ontario.
Dianne Saxe, Environmental Commissioner of Ontario. Photo credit: Environmental Commissioner of Ontario.

“Of course good ideas need trial and error phases, and overnight results are not to be expected. But as phosphorus control programs roll out, they will need the rigour of clear targets, and strong, ongoing evaluation,” Environmental Commissioner Dianne Saxe states in the report.

To illustrate the algal bloom trend, Saxe reports on the significant increase of algal blooms in smaller inland lakes, especially on the Canadian Shield, since the mid-1990s, as documented by the Ministry of Environment and Climate Change. Further reductions are needed, the report states, to avoid another crisis like the one in the City of Toledo, Ohio in 2014, when its water supply became contaminated with toxins from an algal bloom in Lake Erie, leaving almost 500,000 people without access to safe drinking water for days. If these trends continue, the report suggests that algal blooms could hurt tourism, lower property values and damage other sectors of the economy in the Canadian Lake Erie basin by more than $270 million. Additionally, the season for algal blooms now appears to be extending to as late as November, states the report.

Saxe uses the term “non-point sources” to describe the phosphorus impact from places such as farms, construction sites and golf courses. The report notes that erosion rates at construction sites can be 3 to 100 times greater than crop lands, and that only 5% of Ontario’s golf courses have opted to be certified under a voluntary program offered by the Audubon Society to minimize nutrient run-off and monitor phosphorus. Saxe notes that the State of Virginia now requires all golf courses to complete nutrient management plans, including soil tests. In contrast to Ontario, Saxe notes that jurisdictions like Manitoba and Indiana have set strong prohibitions on the winter spreading of fertilizer.

The report also highlights programs such as the voluntary Environmental Farm Plan Program, which has a partial mandate to protect soil and water quality, yet does not measure its own impact on phosphorus run-off or other water quality concerns. Additionally, the report looks at Ontario’s Nutrient Management Act, 2002, which regulates manure produced by certain livestock farms, yet does not provide data to show whether the law has been effective at reducing nutrient loadings from manure.

“The Government of Ontario’s preference so far for addressing phosphorus in runoff has been through voluntary and unevaluated programs, with questionable effectiveness. The government must apply new financial, regulatory and land use planning tools,” states the report, which adds that climate change has only resulted in more rain falling on bare farm fields and further erosion of soils, worsening phosphorus runoff.

Municipalities also have a significant role to play in reducing phosphorus loads, Saxe says. Lawn fertilizers, soil, dust, litter and pet waste all add phosphorus to stormwater “as it races across urban pavements and roofs,” the report states. Regularly monitoring and dredging stormwater management ponds can cut phosphorus loads by 50% – 80%. However, most municipalities tend to underfund their stormwater management programs.

It’s an issue addressed in Saxe’s 2016 report, Urban Stormwater Fees: How to Pay for What We Need, where she estimated that Ontario’s municipalities are facing a $6.8 billion deficit to fix existing stormwater infrastructure and accommodate future growth. Saxe recommends that the province require municipalities to recover full capital, operating, maintenance and research costs for stormwater management going forward.

In 2015, Ontario signed an agreement with the governors of Michigan and Ohio, collectively committing to reduce the total load of phosphorus entering Lake Erie’s western basin by 40% as of 2025.

Halogen-DEC17

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