There is a canoe put-in on the Rideau River known as "Thomson's Landing." It is marked by a six foot high stake, against which Mr Harry Thomson (for whom the put-in is named) tracked the height of the Rideau River's spring flood for almost 50 years.
Mr Thomson's widow, Sheila, was kind enough to share some of his river records with me. I've scanned his original records for 2009 and 2010, which you can view by clicking on the small icons at the left of the blog.
I've also charted the data (see below). The evidence presented in the diagram below suggests that peak water levels have been declining steadily over the past 35 years.
A good analyst, however, pays close attention to missing observations and asks: why are they missing? The data for the missing years was collected, but was not part of the summary sheet Mr Thomson prepared for friends and neighbours. I suspect they weren't included in Mr Thomson's summary because they were uninteresting, that is, they had had low water levels. However even if all the missing years are coded as zeros, there is still a significant downwards trend in the peak of the spring flood.
But could something else be causing the change? Currently winter ice is cleared from the Rideau River using a combination of blasting and a floating back-hoe called an Amphibex. (The Rideau River, like the Red River, flows north. Because the southern stretches of the river thaw before the northern ones do, the river is highly susceptible to flooding.) Could higher water levels in the late 1970s result from different flood control techniques? It is a possibility, however a 1990 article in the Canadian Journal of Civil Engineering reported:
Cutting, using a circular ice cutter and manual labour, is used in conjunction with blasting to remove the ice cover on the Rideau River in Ottawa. This annual program has proven to be an effective means of preventing ice jams. Although the cost is significant ($180,000/year in 1985 dollars), the resulting annual flood control benefits are high ($2,000,000/year in 1985 dollars).
By all accounts, except for an ice jam in 1981, the ice removal program has been effective for many years.
What does all of this have to do with economics? There are probably hundreds, maybe even thousands, of people across the country like Mr Thomson, carefully recording the minutia of their everyday lives. It doesn't take long to scan or transcribe the records. Once they're made available, they can be incorporated into meta analyses, used for elementary school science projects, or just generally give enjoyment to people.
My latest piece in Economy Lab argues that the federal government could provide a valuable role in providing the infrastructure necessary to bring records like Mr Thomson's together, and preserve them for future generations.
Beautiful! The records from the '70s and '80s match the pattern of snowfall as I remember it. Lots of snow in the '70s and little in the '80s. But childhood memories being what the are, the official record may refute my account.
Posted by: K | March 22, 2012 at 09:47 AM
K - If you have childhood memories of Ottawa, Thomson's Landing is right by what was once Brighton Beach.
Posted by: Frances Woolley | March 22, 2012 at 10:16 AM
It would be amazing to see the federal (or even provincial) governments do something like this. Even if they compiled all the data the actual agencies had collected like this into an easily accessible database it would allow a sea change in the kind of environmental science we could do. I'm pretty skeptical of it ever happening though, given that even getting data you know exists out of the agencies can often be like pulling teeth.
One thing I would love to see would be for a government to step up and say that one of the essential tasks of any agency that systematically collects scientific data is to put it up rapidly, in an easily accessible cross-department compatible format. Even if they had to cut down the amount of actual research happening to pay for it, I think the gains would be pretty impressive.
Posted by: Eric Pedersen | March 22, 2012 at 11:28 AM
Good idea. But hang on though, why does it have to be the government?
Posted by: Nick Rowe | March 22, 2012 at 11:38 AM
Eric, what do you think of the environmental data at data.gc.ca, or the similar sites in the US, UK, Aus, NZ?
I'm been thinking today of the potential of this for financial analysis. Right now publicly traded companies must publish their financial statements, which contain various key numbers. There are all sorts of commercial companies that take those financial statements, enter the information, and then sell it for vast sums - I mean serious dollars. As a result only people in well-financed business schools can afford to do financial economics. (Stats Can also collects firm-level data - now there are data walls, and there are data barricades that one can only get access to by giving your first born child to the gatekeeper. The firm level data is behind a data barricade).
Posted by: Frances Woolley | March 22, 2012 at 11:41 AM
Nick, nothing has to be government. Not national defence, not lighthouses, not flood control schemes.
But I think there's a much stronger case for saying that, say, a web site where data can be posted and hosted in a standard format is a public good than that, say, roads are a public good. Just think of it as an electronic library or archives.
Basically it's just way less hassle to finance something through taxpayer dollars than to try to collect the nickels and dimes that would reflect the marginal cost of use.
I just received an email from someone responding to my Economy Lab post saying "I have all of this data I would love to post somewhere, where can I do that?" to which I had to reply "sorry, no idea."
Posted by: Frances Woolley | March 22, 2012 at 11:47 AM
Nick: It doesn't have to be the government; there are already quite a few public data projects in ecology and environmental sciences (the Christmas bird count springs to mind). The nice thing about governments is that they stick around long enough to keep some continuity (hopefully) in recording and organizing data. (non-profits can also do a fantastic job of this... I've always been impressed with Nature Sask) If I were to try and get a grant to take say three years to convince people to collect data on say mussel counts in a river, it would eat up all my time trying to organize, and I'd get a tiny time series. If there's a larger body collecting it, it can easily become worthwhile. The other plus is that the government has broad enough interests that you could theoretically get data from a very broad range of community sources easily.
Frances: data.gc.ca looks interesting (although they don't yet have any of the population data up that would interest me). I've been a bit jaded from dealing with DFO, but it may be a bit harder to get data from than the other agencies. However, it'll need a lot of work to make the interface usable to for easy analysis, and I worry that people may try to keep interesting data sets in house, rather than posting them.
Posted by: Eric Pedersen | March 22, 2012 at 12:06 PM
This is one dataset, one point per year for just 35 years, od whch 25 % of data are missing, and with very questionable accuracy.
Ottawa does some ice breaking actions since over 100 years, to nearly half a million $ per year, precise preparation and timing. There should be data for several flood measurement stations, for every single day, probably 4 or more data points per day, complete, systematic, with analysis of when to do what, and with what results, synchronized between the differnt measurement stations, in short 100 000 times more data with a 10 - 100 x higher data quality.
Soo, what good do these very anectodal river keepers data serve ?
at 0.5 Mio $ / anno somebody should be (I am sure "is") judging the efficiency of what was done in what year at what cost with a lot better data.
And "meta analysis" is nearly all cases like "metaphysik". It is NOT real analysis or physics, but just a collection of biased insignificance.
Prof Woolley, and others,
show me your favourite one or two "meta analysis" studies of the last, lets say 30 years, which revealed something new,
and which I can not talk into the trash withing 15 minutes. I am curious and waiting.
To collect private peoples observations, as a kind of "thick description", nice, good, should be done.
But please dont expect any kind of "analytical" benefit of it.
Posted by: genauer | March 22, 2012 at 12:51 PM
genauer "There should be data for several flood measurement stations, for every single day, probably 4 or more data points per day, complete, systematic, with analysis of when to do what, and with what results, synchronized between the differnt measurement stations, in short 100 000 times more data with a 10 - 100 x higher data quality."
That's what I thought, too, but no. There's flow data, but the level data only goes back about 10 years - search "rideau river" for yourself here.
http://www.wsc.ec.gc.ca/applications/H2O/index-eng.cfm
Levels and flows are correlated, of course, but without historical data one doesn't know the exact relationship between flows and levels.
Remember that Canada has more rivers per capita than just about any place else in the world, so we don't keep track of all of them.
Posted by: Frances Woolley | March 22, 2012 at 01:01 PM
There's one problem Frances. The Rideau is a controlled river. It is one of two such canal systems in Ontario, the other being the Trent-Severn, along which I grew up. Water level control on the Trent and I strongly suspect on the Rideau has changed since the 1960's. The waterways have tried to maintain a more "natural" flow pattern without surges or abrupt water level changes. Environmentalism has strongly influenced waterway management.
For instance in the 1960's the Trent did a lot of work on the dam downriver from our cottage. They dropped the waterlevel in our reach down to a trickle, the river is normally a kilometer wide. That is extremely damaging to habitat and it would not be permitted today except in exceptional circumstances, they'd use a cofferdam instead.
Flooding in the Rideau is a result of not only cutting operations in downtown Ottawa but of how much water is released upstream by the dams.
@genauer: The Rideau is a controlled canal with dams and locks, except the final reach above Hog's Back Falls is free-running, the canal diverts into an artificial cut that passes by Parliament Hill and the Rideau proper empties into the Ottawa River at Rideau Falls.
Posted by: Determinant | March 22, 2012 at 01:18 PM
Determinant - it is true that the Rideau has extreme endogenous fluctuations in water levels - e.g. the Rideau river can rise or fall by a couple of feet overnight when the Ottawa portion Rideau canal system is closed/open.
This means that the data need to be interpreted with care. It doesn't mean that they aren't useful. E.g. the official hydrometric data for the Rideau in Ottawa has flows going back to 1933, but the official levels data only goes back to 2002. Mr Thomson's data has level data for specific dates back to the 1960s. There may be biases, but those biases are consistent over time - i.e. the water is measure at the same place with the same stake by the same person. One could take the Thomson data and the Environment Canada, merge the two, and get an improved estimate of the relationship between flow rates and water levels.
Posted by: Frances Woolley | March 22, 2012 at 02:12 PM
In general:
level data are much, much easier to obtain than flow data.
No calibration issues, just somebody looking at some marks at a wall.
The web page shows that their are complete data (daily), at least back to 1933.
And the station started 1901, where have all these data gone ?
Just not available online. For you. Without answering, who you are, why you are interested, and where to get you, if you do stupid things.
Trying to understand anything about this controlled river, without, who did what when at what dam,
based on what information, is pretty useless. And you need this information at least on a daily basis.
And not just a yearly peak.
You canadians have it some damn easy, without much history, borders, neighbors.
I live here in Dresden, after the centennial (some say millenium) flood 2002, http://de.wikipedia.org/wiki/Elbhochwasser_2002
about 15 b$ damage, 21 dead people in the State Sachsen, 17 in Czech, a lot for Germany. In the house I live now, one km from the Elbe, we had the (ground) water up to the first floor, funny pictures of cars floating in the street.
Thinking about the whole situation, what historic data for what rain and flows, levels, simulations, nothing new.
With many things, you know, that certain information exists somewhere, just not available publicly, and definitely not online.
Let us just consider a completely artificial situation, a stream, with several countries along it.
Practically always at very good terms, sometimes in history maybe a little less than perfect.
Actions on dams, flood controls, who builds what, where, are supposed to be communicated and harmonized.
But assume, that in a poor country upstream, some individual in a weak moment, without proper communication, focuses a little bit too much on the interest of his own local communities interests, and unfortunately could not communicate what he did to the releveant upper authorities.
That may catch some folks downstream by a little surprise. just a few billions more damage, a few more dead people.
Now, what benefit would it be, if such stories would be discussed in the yellow press, with all the gory national emotions ?
And who needs such detailed informations, which would show such conclusions, anyways ?
Posted by: genauer | March 22, 2012 at 04:55 PM
genauer - "With many things, you know, that certain information exists somewhere, just not available publicly, and definitely not online."
The point of this post is that, with appropriate data infrastructure, that "certain information" which exists somewhere could be made public and put online. Sure, it could be misused - there are downsides to democracy. But overall the advantages of democracy outweigh the costs.
Who are you and I to judge what's important? Data storage currently costs about a dollar a gigabyte. Set up standard protocols for data entry, and let people enter their data -whatever it is. History is made up of millions of trivial things.
Posted by: Frances Woolley | March 22, 2012 at 05:47 PM
The Rideau River, like the Red River, flows north. Because the southern stretches of the river thaw before the northern ones do, the river is highly susceptible to flooding.
This is, without a doubt, one of the most delightful tidbits of information I've come across. So obvious - once it's been pointed out - and it explains so much. Never realised why Red River floods were so frequent, or understood why Ottawa uses explosives on the Rideau in the spring.
Posted by: Stephen Gordon | March 22, 2012 at 06:37 PM
"And who needs such detailed informations, which would show such conclusions, anyways ?"
I can think of quite a few people who'd be interested, such as:
1. waterway managers who are interested in how changes in waterway regulation is affecting areas away from expensive and rare continuous monitoring systems
2. Researchers working in the area, trying to understand the local ecosystem. The pattern of dam regulation far upstream doesn't really matter much to someone who only cares about how often a given bank got disturbed by high water levels, or what erosion rates will look like in an area. Sure flow rates would be great, but water level measurements are great deal better than nothing.
3. The public being affected by the regulations. How, as a citizen, do I know my community isn't getting screwed when it comes to water regulation, because we're not a politically important, or someone screwed up and just didn't want to admit it? Unless you're convinced that every single person controlling water management is a saint who never tries to cover their butt.
I'm firmly convinced that, without extraordinarily strong reasons to the contrary (such as privacy), the public should have unfettered and straight-forward access to any data collected by their government. Further, the government should help citizens collate data with each other as much as possible. As Frances said, that's democracy.
Posted by: Eric Pedersen | March 22, 2012 at 06:46 PM
Stephen: I too remember having exactly that same "aha!" feeling when I learned about the Red River flowing north and why it mattered!
Posted by: Nick Rowe | March 22, 2012 at 06:48 PM
@ Stephen, Nick Nix aha !
This north /south explanation sounds nice, but it doesnt cut it, really !
Taken from my metrological maps:
temperature profiles with 5 deg C difference in January
0.5 cm / 3 cm * 20 deg * 111 km / deg = 370 km
gives 1.3 deg / 100 km, with an angle of about 45 deg, cos(45 deg) = 0.7,
about 0.91 deg / 100 km river length
in Summer, this trend is somewhat smaller
just 83 m height difference, between Smith Falls and Ottawa River, over a length of about 70 km, gives - 0.64 deg C temperature difference.
It is cooler in the height:
lapse rate 6.5 deg C / 1000 meter, * 83 m height = + 0.54 deg C temperature difference.
http://en.wikipedia.org/wiki/Lapse_rate gives numbers between 5 and 10 deg C per km
a nice picture:
http://www.kansasflyer.org/Documents/AltitudeTheory.pdf page 2
Sum:
- 0.1 deg C difference between Ottawa and Smith Falls predicted, forget it as an explanation.
Local variations of wind patterns, flow speed, etc are way more important.
now lets look up temperature measurements (14 day average for today, via
http://www.theweathernetwork.com/fourteenday/caon0626/table?ref=tabs_14day_table )
Ontario -4 to 5 C
Kemptville -4 to 5 C
Merrickville -2 to 7 C
Smith Falls, -2 to 7 deg C:
The real explanation for your thick ice is much easier
http://www.rideauroundtable.ca/state_of_river_report/part6a.pdf
very low flow, because it is used as a Canal, very shallow 1.5 - 2.5 meter -> easy freezing.
with 90 % of water coming from lower Rideau lake, you could easily store this somewhere on the way before Ottawa
Could it be, that they blow up the ice, because they want to use the canal for shipping earlier ?
with 31 locks, water and flow levels haven been actively monitored and controlled for a long time
Stephen, Nick, why did I spend so much words on it ?
Because it shows a typically problem of economists. You are already happy with the right sign for an effect, and most of the time do not care about the magnitude and other effects,
like for the northern red river the fact that it is extremely young (9000 years) and therefore extremely flat.
There are many other rivers flowing north without known inverse thawing issues.
@ Frances
That certain data are not widely available, is a political decision, and these decisions are made daily in our democracies. There is nothing new about that. I have tried to give an example, why there can be good reasons for that.
I said already that I do not oppose collecting data, just make sure that you collect all the relevant circumstances.
By the way, what does this "river keeper" Mr Thomson actually do for the river.
I dont find him here: http://ottawariverkeeper.ca/about/staff_and_board/
Again, show me just one single "meta analysis" of which you think it produced some new insight or real significance !
Posted by: genauer | March 23, 2012 at 03:08 PM
genauer - Mr Thomson is not listed because he passed away a couple of years ago, and slowed down a bit before that - he was in his 80s (I think) when he passed.
The Ottawa stretch of the Rideau River is different from the Rideau canal - the canal isn't blasted; it's drained of water in the winter; the Rideau in Ottawa is only borderline navigable - one can use motorboats on the river, but generally the only time one sees motorboats is when they're putting the swans on the river, or taking them off again (don't ask.)
You're right that flow rates are very important for ice formation - as those of us who like to skate and ski on frozen rivers are keenly aware! - but it's also true that average temperatures can be very misleading, because around here the weather is so rarely average.
I don't know how much is due to dams and how much is due to weather, but I do know two things.
One: the south flowing Ottawa River peaks about a month later than the north flowing Rideau River.
Two: there is one heck of a lot of water in these systems, and lots of people near the water's edge - there is only so much one can do to control the flow.
Posted by: Frances Woolley | March 23, 2012 at 03:47 PM
As a certified lock rat, the Rideau isn't natural. Sorry Frances, it isn't. It's a slackwater canal, the same as the Trent-Severn. The Rideau Canal was constructed in the 1830's, the lower reach of the Trent Canal system in the Trent River proper wasn't completed until the 1920's.
The Trent River in its natural state would be three metres deep and 20 metres wide, as would the Otonabee, the continuation of the Trent Canal north of Rice Lake. The Otonabee has a pair river, Indian River, which is just like that because it wasn't turned into a canal.
The Rideau, like the Trent, stores water in reservoir lakes during the spring thaw. This water is designed to ensure a constant waterflow over the navigation season. There is a lot of active control of water levels, even during spring flood. There is a maximum that the dams can pass, the Trent reached that out eight years ago when we had a very went spring. The dams were open full and we still had flooding. As a navigation canal the Trent doesn't have flood mitigation features. Navigation was closed for the Victoria Day weekend which hurt a lot.
The Rideau is blasted not just because it's a north-flowing river but because that particular reach has no floodplain. The City of Ottawa has built right up to the banks and there is a lot of high-value real estate there. The land is low, Lower Town used to be a swamp, yet today Ottawa comes very close to the river edge.
To be fair, Southern Ontario has strong microclimates around Lake Ontario which influence spring thaw based on distance from the lake. Certain areas can be bare and others are still snow covered.
Posted by: Determinant | March 24, 2012 at 12:59 AM
So, the story looks like this:
first you built the Canal (finished 1832)
The settlement of the canal workers (start 1826) then becomes Bytown, after Colonel By.
The Canal is not the main water throughput, and most likely not the reason for the flood danger.
1857 selected for capital "Ottawa".
http://en.wikipedia.org/wiki/List_of_Ottawa_neighbourhoods
The insurance plan gives a good idea about settlements around 1900.
So the basic deal is: yearly blasts against turning the swamps into nice real estate at the center of the capital.
half a million $/yr at a discount rate 1 % = 50 m $, at historic 100 $ / m^2 just 0.5 square km would be worth it.
at 5000 people per sq km, just 2500 people, and for 50 m$, you can not built a basin anywhere near. Makes sense.
And with the lock capable of just 8 meter width, 25 meter length, 1 meter depth, not so much use anymore.
@ determinant, "lock rat" : - )
you might be interest in, for comparison:
http://en.wikipedia.org/wiki/Rhine%E2%80%93Main%E2%80%93Danube_Canal finished 1992 !
width 11 m
length 110 m
carry depth 2.7 m (minimum canal depth 4 m)
lifting boats in total over 100 meters
yearly transport 6 Mio t
length of canal: 170 km
cost: 2.3 b Euro
discount rate used for decision 2.8 %
4 control stations (each 2 people day shift, 1 night and weekends = 4 per week, vacation 5)
4 x 5 x 100 k = 2 m Euro / a
finally nicolas stern report in 2009, discount rate used 1.5%
@ Eric, Frances
One example that very interesting information is not publicly available, "because people cant handle the truth" is, what value for a human life goes
into which calculations for street safety, medical decisions, how many emergency support stations around the country, etc.
These calculations, and decisions based on that, are done, on a daily basis, explicit or most the time hidden implicit.
Or do they tell you that in Canada ? links ! How deal people with that ?
Posted by: genauer | March 24, 2012 at 04:41 AM