Binational Plans Call for 40 Percent Reduction to Algal-Fueling Nutrients

By Kevin Bunch, IJC

lake erie satellite
Satellite imagery shows a relatively mild blue-green algae bloom from 2004, at left, and a worse one from 2011, at right. The goal of binational nutrient reduction plans is keep blooms from being worse than 2004’s in most years. Credit: ESA/MERIS, processed by NOAA/NCCOS

The Canadian and US governments have each issued domestic action plans to combat Lake Erie’s algal bloom problem and reduce the flow of nutrients into the lake.

The governments hope to reduce the amount of nutrients – notably total phosphorus and soluble reactive phosphorus (a type mixed into water and readily usable by plants) – entering Lake Erie by 40 percent compared to 2008 levels by 2025. It’s an effort to reduce the size and intensity of algal blooms (including toxic cyanobacterial blooms) in the western basin and of hypoxic – or low-oxygen – zones in central Lake Erie.

To aid in this, each country has come up with a plan to reach that goal. The Canadian government developed and issued a singular joint plan with the province of Ontario, finalized and published in February following a public comment period in 2017. A United States plan summarizing federal and state actions was published in March, and is based in part on draft plans by Michigan, Ohio, Pennsylvania, and Indiana.

The plans identify actions each government can undertake to support phosphorus reduction efforts, along with areas where new legislation could strengthen efforts. They also commit Canada and the US to research phosphorus loading into Lake Erie’s eastern basin, and find out reductions the nations should target in the future to deal with excess Cladophora algae growth.

A Triennial Assessment of Progress report issued by the IJC in November included several recommendations to governments on the nutrient issue. It noted that blooms have worsened in recent years despite voluntary agricultural programs to reduce phosphorus loads. Both domestic action plans rely on voluntary programs and initiatives to reduce loads, with few mandatory measures.

The IJC previously recommended load targets in 2014 under a Lake Erie Ecosystem Priority (LEEP) report:

the IJC finds that current knowledge is sufficient to justify immediate additional effort to reduce external loading of nutrients to Lake Erie.  In particular, the IJC highlights dissolved reactive phosphorus (DRP) as a primary concern and focuses on the Maumee River watershed as the highest priority for remedial action, recommending a 37 percent reduction for the spring period (March-June) compared to the 2007-2012 average.

The Canada-Ontario plan commits the province and federal government to improve watershed planning with stronger ties to municipalities, conservation authorities and indigenous communities to identify phosphorus sources and the best ways to reduce the amount reaching the water, and to restore wetlands and other natural barriers that can hold phosphorus back from the open waters of Lake Erie. The plan includes specific proposals to promote changes to wastewater management and infrastructure in urban areas, and for agricultural land practices.

The US plan echoes the Canadian plan in many respects, seeking out areas where new regulations will be needed, identifying where governments could beef up voluntary programs, and restoring streams and wetlands where possible. The plan notes there are new technologies that could help reduce phosphorus loads entering the water, and that more data needs to be collected on the more bioavailable forms of phosphorus – which could help identify potential sources. Some states have more work to do than others; while Michigan, Ohio and Indiana are working on reductions to the western and central basins of Lake Erie, Pennsylvania is contributing very little to the central basin’s nutrient pollution, and the US plan indicates the state expects its targets to be met without much trouble. New York has agricultural and municipal sources of phosphorus that can enter Lake Erie, but the action plan says not enough is entering the lake from the state to be impairing water quality; it nevertheless plans on reducing phosphorus loads.

On the urban side of things, most single-point sources for pollutants – such as water treatment plants or industrial sites – have already seen drastic reductions in phosphorus since the 1970s, leaving what’s known as “nonpoint sources.”  These may be pollutants from sewer overflows, or waste washed into the water system during a storm.

Ontario is aiming to establish a legal effluent discharge limit of 0.5 milligrams per liter of total phosphorus from municipal wastewater treatment plants that push through 3.78 million liters of water each day by 2020. Ontario also will work with municipalities to upgrade those water treatment plants, reduce the number of combined sewer overflows through infrastructure improvements, and promote green infrastructure that can help reduce runoff. The communities of London and Leamington have specific goals to upgrade wastewater collection facilities, and for the former, separate the wastewater and storm sewer systems.

The US is aiming for upgrades and inexpensive optimization methods of water treatment plants to reduce phosphorus releases, alongside encouraging green infrastructure investments to reduce runoff from stormwater. The United States also wants to identify and correct failing home sewage treatment systems, which can leak phosphorus into surface and groundwater, incorporate watershed considerations into land use development planning, establish buffer zones to intercept runoff, and phase out residential phosphorus fertilizer applications.

canada ontario action plan

Due to changes in agriculture in Ontario, the Canadian action plan says less hay and wheat is being grown on farmland. These cover crops can help keep soil and nutrients from running off into the water system during the spring melt. As part of its action plan, Canada wants to encourage farmers to plant cover crops to help hold the soil in place. The government also plans on expanding its promotion of voluntary best management practices to get farms to use several at once, where applicable. Ontario will work with communities to restore native wetlands and riparian habitats, focusing on areas where phosphorus loads are high and natural cover is low.

us action plan erie

The US plan targets cover crops and crop rotation to reduce soil erosion, and promotes reductions in nutrient applications on frozen ground, saturated soils and prior to major rainfall – which Ontario is considering doing legislatively. Much of what’s in the US plan involves voluntary best management practices (albeit with continued evaluation of effectiveness), and no new regulations are being called for on the federal level. The plan notes that an estimated 99 percent of farms in the western Lake Erie basin are already using at least one conservation practice, and will need to implement multiple ones to make progress.

On the legislative side, Canada is working on changes to its Feeds Regulations that would remove minimum nutrient levels for livestock feed – in turn giving the industry more flexibility to decrease levels of phosphorus in animal feed where it makes sense.

On a federal level, the US has been working on a variety of research and modeling programs, as well as financial and planning assistance for conservation practices through the US Farm Bill and the Great Lakes Restoration Initiative. These can help local stakeholders and state governments as they work to achieve their respective phosphorus reduction goals.

Even with nutrient reduction efforts, government agencies will still be contending with climate change, which could bring changes to the frequency and severity of rainfall events that can wash more nutrients into the water system, new sources of phosphorus, and the amount of nutrients already in the lake. To contend with those factors, both nations follow “adaptive management” principles for their domestic action plans. What this means is that as knowledge of the ecosystem improves and as efforts get underway to bring down phosphorus loads, Ontario, the states, and the federal governments will regularly review the domestic action plans and adjust them accordingly.

The governments put the plans together under the Great Lakes Water Quality Agreement’s Annex 4, which discusses nutrients and algal blooms.

An IJC Fertilizer Application report released in February found gaps in information gathering, policy and management that should be addressed to get a better handle on the nutrient issue. These could include changes to tilling and crop management and tile drainage in agricultural areas, and adjusting future phosphorus targets as the climate changes and potentially becomes wetter.

The IJC’s Triennial Assessment of Progress report also repeated a 2014 recommendation that Ohio declare the western basin of Lake Erie impaired under the US Clean Water Act, which would trigger a federally mandated maximum daily nutrient load for Michigan, Ohio and Indiana. Michigan declared its portion impaired in 2016. Ohio followed in March 2018.

Should the reduced levels of phosphorus called for in the domestic actions be achieved, the governments hope to minimize hypoxic dead zones, drastically reduce bloom conditions similar or smaller to those seen in 2004 and 2012, and keep the biomass of cyanobacteria low enough that it won’t pose a threat to human or ecosystem health.

Kevin Bunch is a writer-communications specialist at the IJC’s US Section office in Washington, D.C.

A Land Trust Protects Lake Erie Through Conservation and Restoration

By Chris Collier, Black Swamp Conservancy

Robust land conservation involves an ongoing focus on protecting and restoring properties. Success is measured not only in terms of projects completed but in making a meaningful difference in the community for people and the environment. For 25 years, Black Swamp Conservancy has worked to protect Ohio’s natural heritage and ensure that it is preserved for future generations.

Formed in 1993 by citizens concerned with the rate of rural land development, the organization has protected more than 17,000 acres of land across northwest Ohio. Most of the work throughout our history has been protecting land through conservation easements with private landowners. These agreements permanently protect lands like natural areas and family farms from development. The conservancy also has used these agreements to create public parks, increasing public access to natural areas. This work has resulted in the protection of some of northwest Ohio’s best kept secrets and scenic landscapes.

lake erie shoreline black swamp conservancy
Lake Erie shoreline. Credit: Art Weber

In the past decade, harmful algal blooms have come to define the Western Lake Erie basin. With this ongoing threat to our region’s water quality, the conservancy has placed a new focus on projects that incorporate strategies to improve water quality. This resulted in the organization’s first foray into large-scale restoration. Using funds from the US Great Lakes Restoration Initiative, Ohio Environmental Protection Agency, US National Fish and Wildlife Foundation, and the Clean Ohio Green Space Conservation Program, more than 60 acres of wetlands and natural stream corridor and 80 acres of upland buffer habitat have been restored at our Forrest Woods Nature Preserve near Cecil, Ohio. This project is located at the confluence of Marie DeLarme Creek and the Maumee State Scenic River, which means the restored wetlands are treating all the water from the Marie DeLarme Creek watershed before it enters the Maumee, the largest tributary to Lake Erie.

restoration habitat forrest woods
Restoration of 60 acres of wetlands and 80 acres of upland buffer habitat at Forrest Woods. Credit: Black Swamp Conservancy

(See also: “Integration is the Solution: Ontario’s Integrated Watershed-based Approach for Managing Natural Resources”)

With the success of the Forrest Woods project, the conservancy is planning several new restoration projects, including the next phase of our Forrest Woods project to restore more than 4,000 feet of floodplain along the Maumee River. Additionally, we are working with the Sandusky County Park District to restore two sites along the Sandusky River that bookend the city of Fremont. This will create two new public parks with fishing and paddling access, improve water quality and provide spawning and nursery habitat for important sport fish, including walleye and white bass. We also have formed a partnership with the Wood County Park District to restore a 10-acre, edge-of-field wetland, as well as 10 acres of associated upland, at the district’s Carter Historic Farm. This project will be used to demonstrate how wetland restoration and agriculture can coexist on the same property to improve water quality without impacting farm viability.

These projects demonstrate our commitment to protecting the region’s natural and agricultural heritage, which has led the conservancy to launch a new farm access program. This program will assist aspiring farmers hoping to create sustainable farms that market their products locally, by helping them overcome the most common barrier to entering the agricultural world: the high cost of land. To accomplish this, the conservancy will purchase farms, restore marginal areas, lease the land to beginning farmers, and work with tenant farmers to establish agricultural best management practices to protect water quality, improve soil health and reduce erosion. This program will help to protect Ohio’s agricultural heritage, improve environmental quality and bolster local economies.

black swamp conservancy paddles canoe rivers streams ohio
Black Swamp Conservancy leads regular paddles along the rivers and streams of northwest Ohio. Credit: Black Swamp Conservancy

These are but a few of the ways that Black Swamp Conservancy is working in northwest Ohio to improve our communities. This work would not be possible without the support of generous donors, volunteers and landowners.

If you are interested in finding out more, contact us at (419) 833-1025 or Learn more at

Chris Collier is the conservation manager at Black Swamp Conservancy, headquartered in Pemberville, Ohio.

Managing Great Lakes Ice: Preventing Jams and Keeping Water Flowing

By Kevin Bunch, IJC

ice cover st lawrence river
Ice cover was established on the St. Lawrence River by Jan. 10 this year. Credit: International Lake Ontario-St. Lawrence River Board

With winter here, annual efforts to manage ice flows in the St. Marys, Niagara, and St. Lawrence rivers are in full swing. Management efforts in these connecting channels of the Great Lakes aim to prevent ice jams that can cause winter floods and damage to hydroelectric turbines, while contending with difficult or unexpected winter conditions.

In cold seasons, ice typically forms along the Great Lakes and its connecting channels. Unregulated, this ice can take a while to form a solid layer due to currents, leading broken pieces of ice to jam up and cause flooding.

Control structures are in place for shipping and hydropower needs but hydropower dams and ice booms provide a way to influence how ice forms which in turn helps to prevent flooding and protect equipment.

The St. Lawrence River

Prior to dams being built on the St. Lawrence River, ice jams and winter floods were frequent in sections of the river from Ogdensburg, New York, to Montreal, Quebec, said Gail Faveri, co-secretary of the International Lake Ontario-St. Lawrence River Board. Construction of the Moses-Saunders Dam has allowed water managers on both sides of the St. Lawrence a way to control the amount of water flowing out of the river and thus influence how ice forms above and below the dam. By slowing down the velocity, Faveri said, a solid, stable ice cover forms more easily. As ice ages, it smooths out, allowing water flows to increase again without destabilizing the cover.

“When the ice is forming you can lower the flow and slow the velocity, allowing the ice to form (properly),” Faveri said. “Once it gets established, you can go and allow a higher outflow. It functions more like a pipe … and you can drive more water through.”

The gates at the Iroquois Dam at Iroquois, Ontario, also may be used to promote ice formation upstream.

Power companies also install ice booms around Nov. 20 each year between Prescott, Ontario, and Cardinal, New York, to help ice form upstream, Faveri said. Those are handled by Ontario Power Generation and the New York Power Authority, and the IJC is alerted when the booms are installed. Two main booms that stretch across the main channel of the river remain partially open until the Seaway closes to vessel traffic each winter.

Eastern Lake Erie

Now turning upstream, this season’s Lake Erie-Niagara River ice boom was installed on Dec. 16-17 by the New York Power Authority at the outlet of Lake Erie as it has been every ice season since 1964. The IJC issues approvals to the New York Power Authority and Ontario Power Generation to install the boom to accelerate the formation of a naturally occurring ice arch at the outlet of Lake Erie into the Niagara River, said Derrick Beach, secretary to the International Niagara Board of Control. Conditions for the operation of the ice boom are provided in the IJC’s approval to ensure that potential impacts, like flooding to surrounding residents and activities on the lake and river are minimized. The IJC has appointed the International Niagara Board of Control to oversee that the conditions of the ice boom’s approval are met.

“The ice boom reduces the amount of ice that goes down the Niagara River,” Beach said. “The ice naturally (accumulates) in that area on the lake creating an ice arch and the ice boom helps the formation of that natural ice arch that holds the ice back in Lake Erie.”

ice boom New York Power Authority
Lake Erie-Niagara River Ice Boom with ice accumulation from the lake. Each curve along the edge of the ice is where a span of pontoons are anchored to the bottom of Lake Erie. Credit: New York Power Authority

Once the ice arch forms, it naturally reduces the amount of ice entering the Niagara River and the potential of the ice jamming or damaging intakes in hydroelectric power plants along the way. As an added benefit, Beach said the ice boom helps prevent ice from jamming in the Niagara River and causing flooding and shoreline property damage along the river. However, as a floating boom, if high winds or thick ice cause a lot of ice to push against it, the boom will be pushed under water and allow some ice to pass, and then float to the surface again after the ice has passed, allowing some natural transport of ice to continue.

The Lake Erie-Niagara River boom consists of about 1.7 miles (2.7 kilometers) of floating pontoons cabled together, and is maintained by the New York Power Authority on behalf of the hydropower generating facilities on the US and Canadian sides of the Niagara River. Some of these conditions include that the boom cannot be installed each year until the water temperature of Lake Erie drops to 39 degrees Fahrenheit (4 degrees Celsius) or on Dec. 16, whichever comes first. As well, the boom’s approval requires that all floating sections be opened by April 1 unless there is more than 650 square kilometers (250 square miles) of ice remaining in the eastern part of Lake Erie. The latest the boom was taken out was May 3, 1971.

The St. Marys River and uncontrolled channels

Hydropower entities install ice booms in the St. Marys River connecting Lakes Superior and Huron to protect their operations, as does the US Army Corps of Engineers to protect a ferry operator, said John Allis, alternate regulation representative with the International Lake Superior Board of Control and Great Lakes Hydraulics and Hydrology office chief for the US Army Corps of Engineers (USACE) Detroit District. At the start of December, the focus of water managers – much as in the St. Lawrence region – is on reducing water flows using its compensating works flow control structure and hydropower operations so that a solid ice cover can form, allowing a consistent water flow the rest of the winter to reduce the chances of ice jams.

“Even if we could chip ice away from the compensating gates to be able to open them up during the winter, we don’t want to drastically change flows month to month, as you could begin to break up the ice cover and getting that ice flowing, causing ice jams,” Allis said.

ice jam st clair river water levels january usace
An ice jam on the St. Clair River caused water levels downstream to drop the first week of January. Credit: US Army Corps of Engineers

The connecting channel between Lakes Huron and Erie has no control structures, Allis said, but the USACE and Canadian Hydrographic Service (CHS) monitors ice conditions along the St. Clair and Detroit rivers in the winter months in case of ice jams. The US National Oceanic and Atmospheric Administration and the CHS have gauges along the connecting channels, and when a jam is forming water levels can suddenly decline downstream and increase upstream as the water is backed up. When those instances occur, Allis said the Corps notifies the US Coast Guard so it can send an icebreaker to clear the jam before it can cause a flood event along the shoreline.

Kevin Bunch is a writer-communications specialist at the IJC’s US Section office in Washington, D.C.

Less Fertilizer, More Transparency Needed in Western Lake Erie Basin

By Jeff Kart, IJC

western lake erie cattle farm
In the western Lake Erie basin, cattle, swine and poultry are the dominant farm animal operations. Credit: Pixabay

An assessment of fertilizer applications and impacts in the western Lake Erie basin has led to some discoveries. What it didn’t discover is perhaps just as important.

The IJC report was generated by the Great Lakes Science Advisory Board’s Science Priority Committee. The primary focus was on determining the relative contributions of commercial (or synthetic) fertilizer and manure to phosphorus loading.

Phosphorus is a nutrient that aids in plant growth — when it’s used on farmland or lawns and when it runs off into waterways. The western Lake Erie basin has seen a spike in algal growth and harmful algal blooms due to excess phosphorus inputs. The basin also receives phosphorus from wastewater and industrial discharges and urban non-point source runoff. But the greatest source, estimated at two-thirds of the total phosphorus load to the lake, is agriculture.

What’s the magnitude of this? The IJC report used commercial fertilizer sales data, reported rates of application and total manure generation based on livestock numbers within the watershed to derive estimates. Unfortunately, prevailing privacy policies limit access to farm-scale data and information, so the calculated amount is an estimate.

Among the report’s recommendations are that agencies “obtain (e.g. through surveys, available datasets and any new data as appropriate) commercial fertilizer sales and application data at both higher temporal and spatial resolution to allow for improved understanding of this important source.”

study area limnotech lake erie fertilizer report
The study area. Credit: Limnotech

The IJC has previously recommended mandatory standards to get harmful algal blooms under control in the western Lake Erie basin.

The IJC report estimates that more than 41,000 metric tons of phosphorus is included in manure generated and commercial fertilizer applied in the US portion of the watershed. Another 16,000-plus metric tons of phosphorus is included in manure generated and fertilizer applied in the Canadian watershed. This is based on the most recent comparable binational data from 2006-2007, as compiled and analyzed by Limnotech, a Michigan-based consulting firm that assisted the committee in preparing the report.

Most phosphorus used in agriculture comes from commercial fertilizers — an estimated 72 percent between the two countries. On the US side, commercial fertilizer supplies the majority of nutrients at 81 percent. Ontario watersheds receive slightly more phosphorus from manure (52 percent) than commercial fertilizer (48 percent), according to the report, “Fertilizer Application Patterns and Trends and Their Implications for Water Quality in the Western Lake Erie Basin.”

In better news, the report finds that phosphorus fertilizer inputs are declining while more phosphorus is being removed when crops are harvested. However, phosphorus stored in the soil has the potential to contribute to river loads for years or decades to come. The analysis also found that the adoption of appropriate management practices – the timing, rate, location and method of commercial fertilizer and manure placement – may have a bigger influence on phosphorus export from agricultural watersheds than the type of fertilizer.

Control measures enacted in the 1970s demonstrated that Lake Erie eutrophication could be reversed by strategies focused mainly on point sources like wastewater and industrial discharges.

“The challenge this time is with agricultural nonpoint sources of nutrients, which will require a different set of responses,” the report states. “Lake Erie has benefitted from bold action in the past and requires similar bold action today to ensure its health and value to the people of the basin into the future.”

lake erie phosphorus infographic

Jeff Kart is executive editor of the IJC’s monthly Great Lakes Connection and quarterly Water Matters newsletters.

Make It Mandatory: Voluntary Programs Aren’t Enough to Stop Lake Erie Algae

By Kevin Bunch, IJC

stormwater great lakes tap
Untreated stormwater can flow into the Great Lakes, bringing runoff, high in nutrients, along for the ride. Credit: Annis Water Resources Institute-GVSU

While commending governments for establishing targets to reduce the amount of phosphorus entering Lake Erie, the IJC concluded in its first Triennial Assessment of Progress (TAP) report that the condition of water quality in Erie’s western basin is unacceptable.

In its 2014 Lake Erie Ecosystem Priority (LEEP) report, the IJC recommended that governments use more regulatory mechanisms and certification standards on nutrient pollution as a way to accelerate progress in reducing the size and intensity of harmful algal blooms in the lake’s western basin. The TAP report, released Nov. 28, 2017, further recommends mandatory standards and controls, and states that over the past 10-15 years, governments at all levels have been focused on incentive-based and voluntary programs to reduce nutrient loadings. Other organizations such as the Alliance for Great Lakes and the Ohio Environmental Council counter that these voluntary programs aren’t enough to reach the 40 percent nutrient pollution reductions that the governments agreed to target. Those groups – and the IJC – maintain that mandatory efforts are necessary to get harmful algal blooms under control, as 10-15 years of government supported voluntary measures haven’t resulted in meaningful improvements to Lake Erie’s water quality.

The federal governments, as well as the states and provinces that link to Lake Erie either directly or through tributaries – Michigan, Ohio, Ontario, Pennsylvania, New York and Indiana – have to come up with domestic action plans on how they’re going to help reach those 40 percent reduction targets. Some of those governments have already put draft plans forward, including Michigan, Ontario, Indiana and Ohio, but a reliance on voluntary programs in those three states and Ontario leaves the IJC skeptical that they can reach those targets as is.

noaa nutrients lake erie
Nutrients such as phosphorus entering western Lake Erie are causing harmful algal blooms to spring up each year in late summer. This photo is from Sept. 25, 2017. Credit: US National Oceanic and Atmospheric Administration Great Lakes Environmental Research Laboratory

This isn’t to say the IJC doesn’t find merit in these voluntary programs; the TAP reports that promoting incentive-based and voluntary best practices are a critical component to improving the health of Lake Erie. But the domestic action plans should include enforceable standards and timetables for reaching reduction goals, and measurable methods to quantify whether the state or provincial governments are hitting those benchmarks. This may include restoring lost wetlands or constructing new ones, which are an effective way to filter out nutrients before they reach the lake.

Lake Erie’s nutrient problems aren’t limited to the western basin, where phosphorus and other nutrients enter the lake primarily from the Maumee River, and to a lesser extent the Detroit River and the Thames River via Lake St. Clair. Although the problem is much worse in the western basin, pockets of nearshore nutrient and algae problems can be found around the lake. The TAP finds that a major source of nutrients (such as phosphorus) entering western Lake Erie are agricultural operations, including fertilizer applications and concentrated animal feeding operations (CAFOs). Legislative measures to address these sources have been limited; Ohio has passed legislation to keep manure and fertilizer from being placed in winter months to reduce runoff from CAFOs and farms, but there are still thousands of animal feeding operations in Michigan, Ontario and Ohio that aren’t required to get any kind of permit. The IJC’s Great Lakes Water Quality Board has a project underway to look at different manure regulations throughout the Lake Erie region, with a report expected in early 2018.

harmful algal bloom maumee
A harmful algal bloom spreads into the Maumee River in 2017. Credit: NOAA GLERL, Aerial Associates Photography Inc./Zachary Haslick

While agriculture is the primary contributor, failing and leaking septic systems and urban runoff are   important sources of nutrient pollution, too. The IJC recommends governments require periodic testing, maintenance and replacement of septic systems in Canada and the United States.  Urban nutrient runoff from pipes has declined over the past 40 years thanks to a concerted effort to upgrade sewer systems and close off other major direct single sources. But rainstorms and snowmelt can cause sewer overflows and nutrients from lawn care and construction activities to enter waterways. The IJC recommends the promotion and usage of green infrastructure (like rain gardens, filter strips, and engineered wetlands) to continue reducing runoff in those areas.

Finally, the IJC recommends that Ohio follow Michigan’s lead in declaring western Lake Erie impaired under the US Clean Water Act, which would require a tri-state maximum daily load of phosphorus be developed for those two states and Indiana, under US Environmental Protection Agency oversight. This would provide a mechanism to determine how much phosphorus can enter the water system without compromising water quality, and ultimately help restore the lake.

For its part, the IJC’s Great Lakes Water Quality Board and Science Advisory Board have been studying nutrient pollution issues in Lake Erie. These projects include comparing the influence of manure versus fertilizer, reviewing various policies on CAFOs and how progress toward nutrient reduction goals can be measured, as well as studying the link between nearshore nutrient enrichment and offshore nutrient declines.

Lake Erie’s nutrient problems aren’t improving, and more needs to be done to help the lake get healthy again.

Kevin Bunch is a writer-communications specialist at the IJC’s US Section office in Washington, D.C.

Understanding and Solving Lake Erie’s Nutrient Problems

By Jeffrey M. Reutter, retired director of Ohio Sea Grant

lake erie landsat
A large phytoplankton bloom in western Lake Erie on Sept. 26, 2017. Credit: Landsat 8/NASA

Lake Erie is the shallowest and warmest of the Great Lakes. Yet it receives the most nutrients of any of the five lakes, from sources like urban and agricultural runoff. In turn, it produces the most fish of any of the lakes. But nutrients also fuel the growth of the wrong kind of algae in Lake Erie, particularly in the western basin of the lake.

These algae, called cyanobacteria or blue-green algae, have contributed to large “dead zones” where there isn’t enough dissolved oxygen for fish and aquatic organisms to survive. The dead zones form in the cold bottom layer of the Central basin between Sandusky, Ohio, and Erie, Pennsylvania. Similar problems occur in Green Bay, Wisconsin; Saginaw Bay, Michigan, and in many other lakes in the US, Canada and around the world.

These problems are not new to Lake Erie. We faced these same problems in the 1960s and ‘70s.

The Great Lakes Water Quality Agreement (GLWQA) between the US and Canada was originally signed in April 1972, and allowed US and Canadian scientists to reach agreement that excessive phosphorus loading was driving blooms and dead zones, and set targets for total phosphorus (TP) loads to Lake Erie—11,000 metric tons annually.

TP is composed of particulate phosphorus (PP) attached to soil particles, and dissolved phosphorus, most of which is dissolved reactive phosphorus (DRP), or phosphorus dissolved in the water. PP is about 25 percent bioavailable (usable by plants and algae) while DRP is 100 percent bioavailable.

A reduction to a 11,000-metric ton target for total phosphorus under the Agreement was reached in the mid-1980s and the lake responded by becoming the “Walleye Capital of the World.” Coastal economic development and tourism grew rapidly. Today, tourism in the eight Ohio counties that border Lake Erie supports almost 124,000 jobs and has an annual economic value in excess of US$14 billion.

Today, the annual load of TP to Lake Erie is still close to the 11,000-metric ton target, but the amount of DRP in that load has increased by 132 percent. This is the primary driver of harmful algal blooms (HABs) we are seeing today. Elevated numbers of cyanobacteria in the Western Lake Erie basin began to reappear in the late 1990s and have grown rapidly since 2002 with the five worst blooms occurring since 2011.

In May 2015, the Objectives and Targets Task Team of Annex 4 of the 2012 GLWQA issued a final report calling for a 40 percent reduction from 2008 loads in spring TP and DRP loading to the Western basin to address HABs and a 40 percent reduction in Western and Central basin water year loading to address the dead zone.

harmful algal bloom western basin lake erie sept 25 2017
A harmful algal bloom in the western basin of Lake Erie on Sept. 25, 2017. Credit: Aerial Associates Photography Inc. by Zachary Haslick/NOAA-GLERL

These reductions are designed to reduce the severity of HABs, resulting in HABs like the small blooms observed in 2004 and 2012 or smaller, nine years out of 10, or 90 percent of the time. The reductions also are designed to raise the average dissolved oxygen concentration in the dead zone of the Central basin to above 2.0 mg/l (the definition of hypoxic conditions). The US and Canadian governments approved the recommendations in February 2016.

Each of the states surrounding Lake Erie, the province of Ontario, and both countries are currently working on Domestic Action Plans that describe the actions they will take to reach the 40 percent reduction target. A team of scientists prepared a 14-page white paper that summarizes research results and identifies possible strategies to aid managers, decision-makers, and elected officials in developing the best domestic action plans.

The white paper notes that the Maumee and Sandusky rivers are the largest tributary loaders of phosphorus to Lake Erie and the Great Lakes, and 87 percent of this phosphorus is coming from nonpoint sources, of which agriculture is the dominant land use. Mean TP concentrations in these rivers (0.42 mg/l) are about 30 times greater than in the Detroit River (0.014 mg/l), and the Detroit River concentration is not high enough to cause a HAB. While the Detroit is not a major driver for Western basin HABs, the Task Team identified it as one of 14 priority tributaries, and its approximate 2,500-ton load is a contributor to the Central basin dead zone.

Between 2002 and 2013, 70-90 percent of the phosphorus and nitrogen discharged from the Maumee River occurred during the 10 largest storm events each year, according to an article in the Journal of Great Lakes Research by David Baker from Heidelberg University and several co-authors.

According to the white paper, it appears that the four most important sets of actions for farmers to reduce nutrient loading are:

  • Soil-test-informed application rates (i.e., following tri-state guidelines and only applying the phosphorus that is needed)
  • inserting fertilizer into the soil, as opposed to applying it above the soil or mulch layer using techniques known as banding or in-furrow with seed
  • working to control erosion (e.g., filter strips, grass waterways, blind inlets)
  • working to manage and minimize the amount of water leaving a field (e.g., drainage water management).

There are three common mechanisms that can be used to promote adoption of specific management practices:

  • Outreach and education to encourage voluntary adoption of recommendations
  • incentives to encourage voluntary adoption of recommendations.
  • regulations to mandate action.

Voluntary adoption of recommended practices will not occur unless outreach focuses specifically on building farmer’s confidence in their ability to implement a set of cost-effective solutions.

Survey data in the Maumee River watershed indicates that about a third of farmers (equivalent to about one-third of the acres in the basin) are engaged in best practices or are willing to do so, another third are hesitant but considering best practices, and the final third are unlikely to change their practices in the short-term (specific numbers depend on the practice). Those least willing to take additional action to reduce nutrient loss tend to be closer to retirement, and/or farm more rented acreage.

Results from ongoing watershed modeling efforts indicate that there are multiple pathways to reach the 40 percent P reduction target by packaging groups of best management practices together. Each of these pathways typically requires a total adoption level of 50 to 75 percent for each of the practices within the package. A good deal of action will be required to reach those adoption levels as current adoption rates for recommended practices range from 20 to 50 percent on average.

Survey data indicate that targeting those individuals who are currently willing to consider the practice or focusing on the larger farms may be sufficient to achieve necessary adoption levels. Farms greater than 50 acres represent 45 percent of the farms, but 97 percent of the total acres. Over half of the land that is planted is rented, raising the importance of conservation on rented and owned land.

Dr. Jeff Reutter is former director of Ohio Sea Grant and Stone Lab at Ohio State University. He retired in November 2017 but continues to participate on advisory groups concerned with protecting Lake Erie and the Great Lakes, including serving as US Co-Chair of the Task Team.

Predicting and Preventing the Spread of Hydrilla

By Kevin Bunch, IJC

hydrilla mat
A mat of invasive hydrilla found in West Creek in the Cleveland Metroparks system in August 2011. Credit: Jennifer Hillmer

A virulent, hardy, and aggressive aquatic invasive plant has been working its way north, approaching the Great Lakes in a few spots. The plant, called hydrilla, is the target of a binational effort to understand its spread and how it can be dealt with before it gets established. In states like Ohio, its encroachment on the Great Lakes has prompted lengthy eradication efforts as close to the shoreline as Cleveland, and research to better predict its movement in coming years. In Ontario, officials are working to keep the province hydrilla-free.

Hydrilla will root itself into sandy and rich, mucky beds of whatever water body it has settled in and can grow stems up to 30 feet (9 meters) in length, forming dense mats near the surface. Each stem has whorls of small, serrated leaves visible to the naked eye. The plant outcompetes native species for nutrients and can survive a variety of conditions, said Mark Warman, hydrilla project coordinator for Cleveland Metroparks.

It can tolerate less sunlight than native plants, low carbon dioxide environments, and could take advantage of the phosphorus and nitrogen runoff into Lake Erie to expand. It can settle into water up to 49 feet (15 meters) deep and is capable of overwintering in cooler environments like those around the Great Lakes.

Additionally, hydrilla has several reproductive and survival strategies. Warman said in addition to seeds, hydrilla can grow from fragmentation – if a piece of the plant is broken off, both parts may continue to grow, with the free-floating piece attempting to root itself again. Waterfowl can be a vector for transportation, and studies have shown that hydrilla tubers can survive and grow after being regurgitated. Finally, it overwinters with the help of tubers and leaf buds called turions that can be moved in a sediment washout or flood event.

“The biggest risk is fragmentation on fishing equipment and on boats and trailers,” Warman said. “We advocate for proper training in boat inspections and providing infrastructure to properly clean boats, and we let the community know to clean, drain and dry their boats.”

Hydrilla could readily spread at a boat ramp or marina, rendering it difficult to move a boat through without some plant management, he added. The US National Oceanic and Atmospheric Administration notes that hydrilla has caused millions of dollars in damages to irrigation and hydroelectric power projects in the southeastern United States, with the local fishing and tourism industries also taking a hit.

The dense hydrilla mats along the water surface can cause problems not only for boaters and anglers, but also for irrigation and water intake systems, said Francine MacDonald, senior invasive species biologist with the Ontario Ministry of Natural Resources and Forestry (MNRF). The mats also can hurt fish abundance and distribution in the areas they’re found as they change the habitat around them and crowd out native plants, MacDonald said.

Besides watercraft, the water garden trade is another major avenue for hydrilla’s spread, Macdonald said. Hydrilla can be mistaken for other species or mixed in with the roots of other pond plants. The species is prohibited under the 2016 Ontario Invasive Species Act, which makes it illegal to import, possess, deposit, release, transport, grow, buy, sell, lease or trade in the province. The act also includes measures to help control and eradication responses in case it’s found in Ontario, though so far it hasn’t been detected north of the United States.

Completely eradicating the plant in a specific area isn’t easy. Warman said hydrilla was first detected in 2011 at the Cleveland Metropark system in the Cuyahoga River watershed in six locations (all artificial wetlands), and a rapid response plan went into effect to begin hitting it with herbicide. Those treatments, using fluridone-based herbicides, can take seven to 10 years to complete. This year they’ve only found a single tuber; 2016 was the last year his staff found any vegetative hydrilla at the initial discovery site.Other than herbicide, hydrilla control methods are a mixed bag, according to information from New York Sea Grant and Cornell State University.

Mechanical cutters are expensive to run (around US$1,000 per acre) and there’s a risk that fragments could be carried elsewhere; the same is true of suctioning out the plants using vacuums. Biological control using other nonnative species is risky and has seen mixed results in Florida; while grass carp has been successful in small lakes it is a nuisance otherwise in the Great Lakes. Drawing down water levels, where possible, can dry out hydrilla, but the tubers can survive to grow once water levels increase again, and other native plants could suffer in the meantime.

Additional searches outside of the metroparks in the Cuyahoga River watershed haven’t turned up any additional plants, but Warman is vigilant. While the species is federally prohibited for trade and sale without a permit in the US, he believes it initially turned up in the metroparks when it was illegally dumped with other aquarium plants.

hydrilla tuber
A hydrilla plant with its tuber, removed from West Creek in the Cleveland Metropark system in May 2012. Credit: Jennifer Hillmer

Even if hydrilla isn’t around the Ohio metropark now, it has continued to creep its way north from the southern United States. Kristen Hebebrand, a master’s student at University of Toledo, has been studying and modeling how hydrilla has spread north, alongside other researchers working on a risk assessment for the US Army Corps of Engineers (USACE) Buffalo District, the USACE’s Engineering Research and Development Center, Texas Technical University, North Carolina State University, and Ecology and Environment Inc.

The assessment is being prepared to identify locations most vulnerable to invasion by hydrilla within the Great Lakes, based on likelihood of introduction and environmental suitability. The assessment and related research work is being done under the USACE’s Aquatic Plant Control Research Program and is funded by the US Great Lakes Restoration Initiative.

The modeling is built on a watershed-by-watershed basis within the United States, focusing on accidental overland transportation by recreational boats. Overall, Hebebrand said, hydrilla is expected to continue to spread in areas with current infestations, and the watersheds surrounding those will be at a higher risk of infestation. While her study isn’t complete, initial results discussed at the International Association of Great Lakes Research (IAGLR) conference in June suggests its biggest gains by 2025 will be in watersheds just south and on the western end of Lake Erie, the St. Clair-Detroit River watershed, and in watersheds around southeastern and southwestern Lake Ontario, which are already infested. Hydrilla also is expected to increase around the Ohio River and the Susquehanna watersheds south of Lake Erie, according to the ongoing study.

Once the risk assessment project is complete, Hebebrand hopes managers and officials can use it to make more informed decisions about early detection and where to prioritize monitoring efforts for hydrilla. Hebebrand said her portion of it should be finished within a few months, but the work is ongoing.

MacDonald said MNRF is working with a binational invasive species program to document the spread and help find hydrilla and other invasive pests, called the Early Detection and Distribution Mapping System. Alongside an Invading Species Hotline, MacDonald said it’s an important tool to enable citizens and conservation groups to report potential hydrilla sightings and other invasive plants. The MNRF also is studying using environmental DNA to help support early detection before plants themselves have been spotted.

The US Army Corps of Engineers Buffalo District is working with Ecology and Environment Inc. to develop a basin-wide collaborative initiative to fight hydrilla. It’s in the early stages, but Ecology and Environment hopes to have a website up to provide a place for managers to share lessons learned and technical information in coming months.

Finally, there are formal commitments from Great Lakes governors and premiers to prevent and respond to aquatic invasive species together, including hydrilla. MacDonald said this includes a mutual aid agreement to combat shared threats within the basin – though so far Ontario has not been asked to assist with any hydrilla eradication efforts. Information on control efforts is shared regularly through organizations like the Great Lakes Panel on Aquatic Nuisance Species and the Conference of Great Lakes St. Lawrence Governors and Premiers’ Aquatic Invasive Species Task Force.

Kevin Bunch is a writer-communications specialist at the IJC’s US Section office in Washington, D.C.

University of Windsor Research Studies Beach Testing, Enlists Citizen Scientists

By Daniel Heath, GLIER

The Great Lakes Institute for Environmental Research (GLIER) at the University of Windsor is a multidisciplinary research facility located on the Canadian side of the Detroit River. Researchers at GLIER address complex environmental problems such as the effects of multiple environmental stressors on large lakes and their watersheds. One of the major concerns for public health around the Great Lakes basin is microbial (bacterial and algal) contamination in recreational and drinking water. The greatest health concern associated with recreational water use is gastrointestinal illness resulting from exposure to bacteria, viruses or protozoa from human or animal fecal sources.

Aside from the direct public health risks, microbial contamination has enormous economic impacts, including beach closures, commercial and recreational fisheries losses, increased water treatment costs and loss of productivity due to illness and imposed protective measures. Water for recreation is a top tourist attraction in North America, which contributes billions annually to the Canadian and US economies. In Canada, Great Lakes recreational water use injected $12.3 billion into the Ontario economy in 2010, while the US National Oceanic and Atmospheric Administration (NOAA) estimates that a third of all US recreational boaters are based in the Great Lakes

Limitations in current monitoring

Public health agencies in Canada and US have used fecal indicator bacteria (FIB) cultures, especially Escherichia coli (EC) for freshwater and enterococci (ENT) for salt water, as indicators of fecal contamination and associated risks to human health. However, there is growing evidence that these cultures may not necessarily correlate well with actual pathogen presence or abundance.

There is also evidence that EC and ENT can survive, grow and establish populations in natural environments such as freshwater lakes and streams, soils and sediments. Culture-based measurements of EC and ENT don’t indicate their potential sources and therefore are of limited value for identifying significant pollution sources and determining most cost-effective mitigation measures.

Further, the approved standard culture methods for measurements of EC and ENT require a minimum of 18 hours for the results to become available, although the state of Michigan recently initiated a rapid genetic test for E. coli.

Studies have shown FIB numbers to be quite dynamic with no correlations observed from one day to the next, which is also true in the Windsor/Essex region of Ontario. These types of fluctuations can result in false positive and false negative errors in beach warnings and closures; false negative errors pose a health risk to beach users.

A example of beach water quality monitoring by the Windsor-Essex County Health Unit.
A example of beach water quality monitoring by the Windsor-Essex County Health Unit.

Role of Citizen Scientists

Given the limitations in culture-based water testing, GLIER researchers are developing rapid, culture free, genomic-based tools (by amplifying the DNA) to provide fast and accurate identification of the microbial community and the probable source of contamination (human, animal or sediment).

To maximize the geographic coverage of the testing, GLIER researchers organized a water quality testing event on Aug. 19. Water samples were collected at 450 locations along Lake Erie, Lake St. Clair and the Detroit River, as well as other small river and stream tributaries with the help of citizen scientists.

Without this involvement, such broad-scale water sampling is close to impossible. Beach testing results using the developed methods in a commercial lab or test facility will take less than six hours. As a research facility, GLIER is developing these techniques and hopes to have the process optimized for use by health departments and other agencies before the end of the year.

volunteer filters water sample lasalle
A volunteer filters a water sample in LaSalle, Ontario.

Future monitoring

In addition to pathogen identification, the GLIER research team is working on models to allow managers and public health officials to identify probable sources of microbial outbreaks and make decisions based on accurate predictions, ahead of time. The developed tools and methodology in this project can be applied seamlessly in other jurisdictions around the Great Lakes, across Canada and around the world.

Dr. Daniel Heath is an evolutionary and conservation genomics professor at the Great Lakes Institute for Environmental Research at the University of Windsor in Windsor, Ontario.

Get Involved: Asian Carp and Excess Algae

By Jeff Kart, IJC

You can make noise about Asian carp and excess algae this month.

A live Asian carp was caught earlier this year, nine miles from Lake Michigan and beyond a system of underwater electric barriers. The US Army Corps of Engineers is seeking public comment on a draft report related to preventing the spread of these invasive fish. Comments are being taken until Sept. 21 on proposed measures at the Brandon Road Lock & Dam in Illinois. The tentatively selected plan is called the “Technology Alternative – Complex Noise with Electric Barrier.”

Click the links above to learn more, and see other highlights below on ways to “get involved” in helping protect the Great Lakes.

map army corps plan
A map showing key features of the tentatively selected plan. Credit: USACE

More Asian Carp: The state of Michigan is offering up to $700,000 in cash awards for a Great Lakes Invasive Carp Challenge. Written proposals are being accepted through Oct. 31 “for innovative methods to prevent invasive (or Asian) carp from entering the Great Lakes.” Michigan officials note that they’re working with other states and Canadian provinces to keep silver and bighead carp – two species of Asian carp – from entering the Great Lakes.

Asian Carp Canada, by the way, is encouraging people to report sightings of Asian carp and other invasive species to EDD MapS (Early Detection & Distribution Mapping System), a binational program that includes Ontario.

Lake Erie: Until Sept. 29, the US Environmental Protection Agency is taking comment on a Draft Domestic Action Plan for Lake Erie. In 2016, as part of the Great Lakes Water Quality Agreement, Canada and the US adopted phosphorus reduction targets for the lake, to address excess algae fed by nutrients. Each country is developing domestic action plans which outline strategies to meet the targets.

Canada received comments on its Draft Action Plan earlier this year. Plans for both countries are to be in place by 2018.

More: This is only a small sample of opportunities for public comment in the basin. See our Twitter and Facebook feeds for daily updates on Great Lakes news, and feel free to send “get involved” tips to Jeff Kart at

Jeff Kart is executive editor of the IJC’s monthly Great Lakes Connection and quarterly Water Matters newsletters.

Forecasting ‘Dead Zones’ to Help Protect Drinking Water

By Kevin Bunch, IJC

Cleveland, Ohio, depends on water from Lake Erie for its drinking supply, which can be affected by a hypoxic zone
Cleveland, Ohio, depends on water from Lake Erie for its drinking supply, which can be affected by a hypoxic zone. Credit: Rick Harris

A new tool in development should help water treatment plants in communities along Lake Erie prepare for when dead zones reach their shores.

Lake Erie is periodically affected by oxygen-poor hypoxic zones, also known as “dead zones” for how few things can survive in them. These zones form at the bottom layers of water in Erie’s central basin. Aside from being bad for aquatic life, hypoxic zones present a special challenge to water treatment facilities. The hypoxic zones can spread toward shorelines and temporarily impede operations for hours as treatment systems are set up to deal with the specific impacts of those conditions. The US National Oceanic and Atmospheric Administration, working with the Cooperative Institute for Great Lakes Research, hopes to lend a hand to water treatment plants with an experimental early warning system that would provide advance notice of potential hypoxic events.

Oxygen-deficient water often has a lower pH balance and may have higher concentrations of metals like manganese and iron, which can cause discoloration of treated water, according to Craig Stow, aquatic ecosystems modeling researcher at NOAA’s Great Lakes Environmental Research Laboratory. Water treatment plants can account for these water conditions, but operators need to know about those conditions to make the necessary treatment adjustments, and it takes time to retool their systems. Right now, they get alerted only when the hypoxic water has reached the intake.

“Hypoxic water can be treated, but it requires knowing hypoxic water is present to put those treatment adjustments in place,” Stow said. “Since these adjustments are more expensive to do or counter to normal treatment goals, you don’t want to be treating water all the time as if it were hypoxic.”

Hypoxic conditions typically occur in late summer, caused by long periods of high temperatures and stormwater events that wash fertilizer and manure off farms, and sewage from combined stormwater overflows into the lake. The nutrient input stimulates algal growth, and as that algae decomposes the aerobic bacteria feeding off it consumes oxygen, reducing the levels of dissolved oxygen in the water.

Lake Erie isn’t a static body – water is constantly being churned around, and occasionally this brings the hypoxic water from the bottom layers of the central basin near the shore and to the water intake pipes located near cities. By adapting an existing Lake Erie computer modeling framework used for other types of forecasts (like meteorology), Stow believes an effective early warning system can be developed to alert water managers that a hypoxic zone could be heading toward their intakes so that managers can adjust their treatment methods accordingly, possibly up to a few days in advance.

The project got underway in 2016. In the initial stages the warning system involved taking existing models focused on water temperature and other conditions and adding hypoxia to it, but chemical and biological components – like phytoplankton growth and phosphorus inputs – will be included later.

An additional goal of the project is to determine whether adding nutrient and biological components to the model will improve the accuracy of the hypoxia simulations over a purely physical model, according to Stow. A model that includes chemical and biological components may have additional applications, such as forecasting algal blooms, which would be helpful for water managers, anglers and boaters.

Seasonal changes through 2005 show how Lake Erie’s hypoxic (low-oxygen) zone develops in the central basin in July through September
Seasonal changes through 2005 show how Lake Erie’s hypoxic (low-oxygen) zone develops in the central basin in July through September. Credit: NOAA

NOAA researchers also are reaching out to groups with a stake in such a warning system. Water treatment and management agencies, Ohio Sea Grant and the Ohio Environmental Protection Agency are just some of those who could use the early warning system.

“The drinking water plant managers not only benefit from sharing operational information and research, but also by establishing lines of communication between water utilities and researchers that help identify common areas of interest,” Scott Moegling, water quality manager at Cleveland’s Division of Water, wrote in a NOAA blog post. “The end result, researchers providing products that can be immediately used by water utilities, is of obvious interest to the water treatment industry on Lake Erie.”

The current effort is focused on the US side of the lake. Stow said Canadian information isn’t available right now, but there have been discussions with Canadian agencies on collaboration efforts.

Ontario has been working along similar lines on its Lake Erie coastline, however.

Communities along the north shore of Lake Erie contend with the upwelling of hypoxic water, according to Todd Howell, Great Lakes ecologist with Ontario Ministry of the Environment and Climate Change. Fish kills have been reported that were linked to hypoxic water reaching the shoreline, and the ministry has conducted water quality monitoring that has confirmed that hypoxic water is reaching the coastline. Upwelling also can push nutrients like phosphorus from the lake bottom to the surface, giving algal blooms an additional food source in the summer.

Howell said the province has acquired and deployed a real-time sensor system offshore of Port Glasgow, located off the central basin of Lake Erie. The system is designed to detect low-oxygen water and upwelling, and was first deployed in late summer 2016.

“Our intent is to deploy the system annually over the May-to-November period,” Howell said.

The Ontario Great Lakes Intake Program has routinely monitored nutrient, chemical and chlorophyll characteristics and concentrations at water intakes along the north shore since 1976. While this has not been specifically developed to detect hypoxic water, the data it has collected suggests indirectly, through phosphorus detections, that there has been upwelling occurring around some central basin water intakes. A 2015 report prepared by Freshwater Research for the ministry recommends collecting more evidence of hypoxic events along the north shore.

Since receiving funding a year ago from the NOAA Center for Sponsored Coastal Ocean Research – which is studying hypoxic zones in the Gulf of Mexico and other waters – Stow said his team has an early version of their dissolved oxygen model online right now. The researchers are working on predicting hypoxic zones and watching to see how reality matches the model, by using profilers and sensor strings in the lake that measure oxygen and water temperature. Those will be retrieved in the fall to refine the model. Part of the project also includes studying how these hypoxic zones form in the first place.

Stow said the early warning system could be operational within the next few years, at which point it would be run by NOAA’s forecasting unit.

Kevin Bunch is a writer-communications specialist at the IJC’s US Section office in Washington, D.C.