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According to the State Journal, "Madison will launch a test project next month to see whether boom-like structures can cut down on the sometimes toxic algae that covers parts of lakes Monona and Mendota during the summer, causing beach closures and endangering swimmers." "BB Clarke on the Near East Side and Bernies on the south shore of Monona Bay will have geotextile fabric barriers placed near or around their swimming areas in an effort to keep algae out."
"The two beaches were closed for a combined 63 days from 2005 to 2009 due to growth of blue-green algae, according to Public Health Madison and Dane County."
"'Our objective is, how can we direct or move these (algae) scums away from our beaches,' said John Reimer, who is helping lead the project for the city's Engineering Division."
Not addressing the real cause
The real cause of the algae blooms is not lack of barriers--it's excess nutrients in the lakes, which stimulate algae growth. The nutrients wash into the lakes because there are too many paved surfaces, and not enough rain gardens and sediment traps.
This is typical of the City's short-term response. Someone complains about a problem, and the Engineering Division applies a Band-Aid.
This Band-Aid is going to cost $60,000 (not including staff time) for just the pilot project at two beaches.
Neighborhood groups meet and debate. Much time is wasted. Officials get credit for looking like they are doing something-- but long-term leadership is lacking, and the underlying cause remains. The algae continue to grow and release their toxins--now just a few feet further from the swimmers.
Let's assume this project gains enough support to be expanded. Assume barriers are adopted for 10 beaches, for a total cost of $300,000 a year. If continued for 10 years, the barriers would cost a total of $3 million. In the end, there would be just as much algae. Probably more, because the city will have grown.
Imagine a more cost-effective response
Street-side swale and adjacent pervious concrete sidewalk in Seattle, Washington. Wikipedia.
Imagine instead, that money is put into rain gardens. Let's assume you can build a large rain garden that takes runoff from streets, for $10,000.* They are equipped with a few benches, becoming a "green oasis" in the city, maintained by local residents or businesses.
For the $3 million spent on algae barriers, you could build instead 3,000 large rain gardens--each one serving as a tiny "park." And--the key idea, at the end of 10 years, runoff of nutrients into the lakes would be significantly reduced.
The trap of short-term solutions
If we take the Band-Aid approach, people are deflected from solving the real problem. If officials had the guts to let the beaches stink, and tell people the real cause was nutrients in the lakes, it could be an important opportunity for educating the public.
How many people would benefited from barriers at beaches? I'd guess it's mostly the residents of those neighborhoods. But they might see some modest improvement this coming summer.
However, if we could install instead 3,000 large rain gardens over 10 years, there would be no visible improvement in the lakes for some years. But the slow improvements would benefit far more people. Everyone who enjoys the lakes, from boaters to people sitting by the lakeside, would eventually benefit.
Besides benefiting more people, the rain garden approach would also involve the community. In contrast, the barrier approach only involves a few paid workers.
Because the rain garden solution doesn't yield visible results at first, it takes strong leadership--and leadership is lacking.
The Engineering Division is like the helmsman on the Titanic. They are just doing what they were told to do: "Full speed ahead, and damn the icebergs!" It's time for the captain to wake up, and give them a new course and a more deliberate speed.
A survey** shows Madisonians are dissatisfied with how city officials are caring for our lakes. Let's hope people aren't fooled by this lame barrier solution for the algae problem.
Large rain garden, taking runoff from parking lot, corner of Struck St. & Watts. Rd.
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* My figures are guestimates. The WSJ says the "pilot program" would cost $60,000 this year, excluding staff time. Probably the unit costs would go down if the project were expanded. My figure for large rain gardens is a guess. I'm simply trying to show an alternate way of looking at the problem.
And it's not just the budget for money--the carbon budget counts, also. For barriers, trucks transport the barriers to the beach each year, burning fuel. The barriers themselves are made from oil. In contrast, rain gardens take carbon from the air and put it into the soil (in roots).
And it's not just the budget for money--the carbon budget counts, also. For barriers, trucks transport the barriers to the beach each year, burning fuel. The barriers themselves are made from oil. In contrast, rain gardens take carbon from the air and put it into the soil (in roots).
** The 2009 "Resident Satisfaction Survey" shows that, in contrast to all other issues, residents are "somewhat dissatisfied" with lake quality, yet they rate the issue somewhere between "somewhat important" and "very important." So on the chart of satisfaction VS importance, the issue of lake quality stands in a class of its own--it's the one big problem where the city is falling down.
Info on blue-green algae poisoning.
Interesting plan to build a regional manure digester, which would help reduce excess nutrients.
Info on blue-green algae poisoning.
Interesting plan to build a regional manure digester, which would help reduce excess nutrients.
Posts
Hi,
ReplyDeleteNice post, glad you're passionate about the lakes. Just wanted to point out that a lot of P (as in phosphorous) going into Mendota comes from fertilizer and animal waste from the farms up-river, not really from the city itself.
Here's a good paper written on it.
http://minds.wisconsin.edu/handle/1793/187
-Luke
Luke,
ReplyDeleteThanks for calling that article to my attention. You are probably right that more of the phosphorus (fertilizer) going into the lakes comes from agriculture outside the city. Unfortunately, that has often been used as an argument for doing little within the city.
The article addresses import and export of phosphorus from the watershed (such as into the soils), not phosphorus actually going into the lake. In addition, for the city, they looked only at fertilizer on lawns. They ignored all other kinds of input to lakes, such as dog waste, leaf litter, ashes, and leakage from sewage pipes. So I suspect the study underestimates urban contributions to lake fertilization.
Anyway, as city dwellers, we need to do our part!
David,
ReplyDeleteYou're absolutely right that as city dwellers we need to do our part too. But it is dangerous to start chasing potential phosphorous inputs that, according to our best estimates, are small or unimportant compared to the real culprits of change in our lakes.
For example, dog waste is likely minimal. You could try estimating it by looking at dog food imports into Madison, but it likely doesn't approach the estimated 700,000 kg/y that just corn fertilizer represents.
Sewage pipe leakage is a tough one, it would be very difficult to estimate accurately. But one could still think critically about it. Due to their buried position, any major leakage would probably show up in ground water impacts before it became a major contribution to the lake (I'm of course not referring to major inputs from sewage placed directly into the lake before proper treatment started).
In the end, this is all about most effectively using state funds to mitigate problems with the lake. It is very likely that one of the most cost effective reductions in phosphorous is not mitigation efforts in Madison, it is most likely working with farmers in the watershed to cut down on field and animal waste runoff. I think this cost-benefit analysis need to be considered.
-Luke
Luke, you are absolutely right that agriculture runoff is key for the big lakes. Cost-benefit analysis is also very important. If ag runoff is your interest, go for it! Everyone's contribution is needed.
ReplyDeleteHowever, for Lake Wingra, urban runoff must be the most important contribution.
Before urban citizens gain the right to preach to their rural brothers, they first have to get their own house in order. The lakes are our recreation, but agriculture represents their income. Urban citizens weigh in with more people, but farmers have a more intense interest in continuing agriculture as they know it. With a City Engineering dept, we have a whole infrastructure that farmers don't have.
In a sense, comparing urban to rural inputs is like comparing apples to oranges. I'm not sure where this leads, except to say, again, that we urban dwellers have to do our part. When you single out one group, even the most important, the whole political thing starts to decend to finger pointing.
We point to the farmers and say, "You're most important, for reason A, so you do something first." They point back and say Urban dwellers are the most important, for reason B. Stalemate.
The science is important, but this goes beyond science arguments. Somehow, we all have to find the will to do something more rigorous, because we all care, and we all want to succeed. When Wisconsinites reach that point of committment, we will all pitch in, roll up our sleeves, and get to work, without asking who is the baddest actor.
I value your comments. It's how we hash out the best approach.