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Revenue From Wetlands

When the health of Lake Erie began to deteriorate in the 1960s, the world noticed. Its problems were visible to millions of people in two countries who live around or near that lake, and it wasn’t hard to find public support for measures to restore it to health.

It’s been different for Lake Winnipeg. While its problems have been in the headlines in Manitoba for several years, the rest of the world hasn’t heard much about it. The problems weren’t even apparent to the thousands who visit the beaches or have cottages around the south basin. The massive algae blooms had mostly been confined to the remote north basin, which is seen only by commercial fishers or the few hundred people who live in lake-shore communities.

That’s changed in the last two years as dense mats of algae, which can harbour potentially deadly toxins, have come ashore on some of Manitoba’s favourite beaches. The images are now being seen across the country and even around the world, such as in CBC’s “The Nature of Things” special last Sunday night, which provided an excellent and balanced overview of the problem and its causes. Agriculture – especially land drainage – was noted as one of the problems, but it was not singled out. There was no finger pointing, and favourable mention was given to farmer-driven solutions, such as direct injection of hog manure and the work of Deerwood Soil and Water Management Association.

If anyone in the program comes across as looking a little suspicious and unco-operative, it’s Manitoba Hydro, which refused to be interviewed for the program. Hydro is responsible for the nutrient-retaining dam at the north end of the lake, at least partly for the damage to the Netley-Libau Marsh, which is now almost a southern extension of the lake. Because Hydro doesn’t ever allow Lake Winnipeg to drop, as it normally would during dry cycles, the marsh doesn’t get a chance to regenerate.

Viewers not only in Canada but in other 40 countries where “The Nature of Things” is rebroadcast will now be aware of the lake’s problems, which cannot be underestimated. The world will now be watching for the kind of collective action that restored Lake Erie to health in the 1970s.

Which leads to this week’s front-page story about the experiment to clean some of the nutrients from the Red River before they reach the lake, and in doing so capture some energy for heat or electricity. Let’s step back and look at some elements of the big picture:

Millions of tonnes of corn are being turned into North America’s gas guzzlers. The economics make no sense without subsidies, and the net energy return is questionable. Not only does corn need energy in the form of natural gas-derived nitrogen, it also uses massive amounts of phosphorus, a nonrenewable mineral resource. Much of it is making it into the Mississippi, creating a problem similar to Lake Winnipeg’s – the “dead zone” in the Gulf of Mexico. Given that much of the Red River’s phosphorus comes from the U.S., some of Lake Winnipeg’s problems can be blamed on flawed U.S. (and Canadian) ethanol policy.

Which leads to another of Lake Winnipeg’s problems. Whether its from a flushed toilet or excess fertilizer application, the lake receives nutrients from an area stretching from the Rockies east to Thunder Bay and south to Minnesota. Those flushed toilets aren’t only from big cities like Calgary or Winnipeg. They are also from every small town with a sewage lagoon.

As anyone who has seen the edge of a slough or sewage lagoon knows, cattails and other marsh grasses grow quite well on their own with zero purchased inputs, producing several more tonnes per acre than domestic crops. Scientists tell us that they absorb large amounts of phosphorus which remains in the ash after burning and can be returned to the land as fertilizer.

An idea must have a lot of merit if it simultaneously produces energy, reduces greenhouse gas, recycles phosphorus and cleans up Lake Winnipeg. However, to achieve these benefits on any scale, there needs to be a change in how the farm and rural community manages wetlands. Virtually uncontrolled drainage over the last few decades has contributed both flooding and excess nutrient loading in Lake Winnipeg. It’s clear that the flow must be slowed, and that will mean holding water back. That won’t necessarily mean restoring sloughs that have already been drained. It could be in new manufactured wetlands strategically designed for flood mitigation and nutrient recovery from livestock operations or municipal sewage.

Given the almost annual flooding problems and the ever-more-visible crisis in Lake Winnipeg, some form of water-retention system is probably inevitable anyway. The cattails-to-energy scheme could mean that it’s accompanied by tangible benefits to the rural community, including jobs related to harvesting and energy production and lower fertilizer bills. This project should get the support it needs so that it can be taken to a commercial level. [email protected]






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