Illinoistocht

My estimate is that there was marginal ice last weekend (okay in spots, but not consistently solid), while given the recent cold temperatures there could be more consistent solid ice, but the ice is buried under a healthy layer of snow that makes it not skateable.  (Worse, with snow cover it’s harder to monitor any potential thin spots).  Illinois may have a few lakes and ponds that have been shoveled, but the cool thing about canal ice skating is that you go somewhere rather than just going in circles.  

For the Hennepin, sometimes the ice can be quite good if conditions are favorable, although most often the water may not freeze very solid at the bridge “pipes” or at the locks due to the current of the canal.  The eastern section of the canal (east of Visitor Center) drops in elevation and has more locks, meaning that the western and feeder sections have longer “portage” free sections.  By using skates with a clip-on blade, you can easily “klune” as the Dutch put it, or portage around the places where the ice is too weak.   (For tours, the Dutch lay out carpets and plywood for the skaters to “klune” around sections where the water is thin under bridges, etc.—they don’t necessarily remove their blades or put on scabbards.)   

The I&M only has 15 miles of the canal in open water between Channahon State Park and Gebhard Wood and 5 miles between Utica and LaSalle, according to Illinois DNR.  I did skate a section of it in 2001 and it had been so cold for so long that even the areas around one of the locks appeared to be solid ice.  The ice was rough but my nordic skates powered over the bumpy and rutted ice, but made the skating slow.  

I was hoping to skate Christmas week as I'll be in the region visiting family, but the snow may make it too difficult and given its the hectic holiday season, I might want to just have another cup of coffee not make the trip from a few hours away.  If there is too much snow for skating, perhaps there will at least be enough snow for some pursuits, cross-country skiing or snowmobiling on the towpath so somebody will get to enjoy winter on the canal.  For me though, I'll have to wait for the weather "stars to align" and hope for good ice skating conditions at a later date...keep me posted if you have a weather report as most of the time I'm at home far away. 

I admit at first I felt a little schadenfreude, a German word for pleasure taken from observing the misery of another, about the Blago drama given his hostility to the Hennepin and I&M (see the blog posts from earlier this year).   But upon further reflection I had a realization that park funding is in jeopardy everywhere.  

In late May, 2008, the National Trust for Historic Preservation named the entire 278-park California State Park system as one of its 11 Most Endangered Historic Places.  Earlier that month, Governor Schwarzenegger had to cut the budget and would have closed 48 of the parks, but then funding was restored on May 14.  However, as the National Trust put it, “the budget for the Department of Parks and Recreation is woefully inadequate to support day-to-day parks operations, much less to address the $1.2 billion deferred maintenance bill that has accumulated through years of chronic underinvestment.”  Two big differences in my perceptions about the governors in California and Illinois were that in California the park funds were quickly restored and the Governator’s ethics compared to Blago’s.  Even though he doesn’t live in the state mansion and commutes weekly (and sometimes daily) back-and-forth to LA, Arnold uses either his own money or his own campaign funds and not the funds of cash-strapped California for the jetting.   And one also presumes that he and his Kennedy-clan wife aren’t desperately trying to figure out schemes to make more money. 

The California drama took place in May which seems like an eternity ago in the world of money—in the stock market, in the economy, and most importantly in local, state and federal budgets.  If early 2008 presented a problem for state parks, what will California do in 2009 with an unprecedented $40 billion budget deficit looming in the next 18 months?  Or how about Illinois?   The nation’s parks may be fighting an uphill battle—while on the one hand the current economic climate is going to result in pressures on government funding, on the other hand, the public seems less supportive of the outdoors in general.  If less people are interested in outdoor activity and fewer people patronize the park systems then they may become less supportive of funding parks with tax revenues.  

By many measurements, there seems to be a decline in many outdoor pursuits.  The Economist recently reported that “…despite an explosion in the deer population, the number of hunters fell from 19.1m to 12.5m between 1975 and 2006.  Fishing has declined more steeply, particularly among the young.”   (Jul 10, 2008).  Fishing has declined in spite of the endless proliferation of bass-fishing shows on cable television while, despite the fact that nearly every mall in America has a store where one can buy Ansel Adams posters, visits to Yosemite National Park have dropped for 9 out of the past 13 years with the number of visitors down nearly 20% over the period.  There are a variety of causes to be sure and any discussion brings out the amateur sociologist in us all—whether its video games or demographics or something else. 

While some parks are maybe seeing more use there are others, like Yosemite, which is seeing less use.  In many places park funding is under siege, whether at the national, state, or local level.   Let’s all hope the parks can come through this new austere budget era unscathed.

Safe ice thickness for various activities requires varying levels of thickness based on the weight of what is venturing out onto the ice.
The guidelines vary based on a number of factors, a chart in the Farmer’s Almanac at http://www.almanac.com/outdoors/safeice.php indicates that ice would need to be roughly 4 inches thick to be considered safe. 

Ice thickness should always be tested before heading out onto any frozen body of water.  There are many variables and factors that influence thickness besides air temperature.  However, an estimate is useful for deciding if it might even be worth bothering with making a trip to your favorite ice skating, ice fishing, or snowmobiling river or lake.  Using a mathematical model is only a start--if the weather conditions seem supportive and the model gives a positive indication, it then becomes worthwhile to spend the time and effort to obtain firsthand observations to verify the true ice thickness. 

The following is a formula from the US Army Corps of Engineers Cold Regions Research & Engineering Laboratory in Hanover, NH:
(See also www.crrel.usace.army.mil/library/technicalnotes/TN04-3.pdf)

Ti = C √ AFDD

where:
Ti = ice thickness in inches
AFDD = Accumulated Freezing Degree Days (in °F days)
C = Coefficient for use in modified Stefan equation with ice thickness in inches, AFDD in °F (see table below)

Condition                            Typical Value of C
Windy lake with no snow        0.8
Average lake with snow          0.5 to 0.7
Average river with snow          0.12 to 0.15
Sheltered small river              0.21 to 0.41

The AFDD is derived from FDD, or
FDD = (32 – Ta), where Ta = Average Daily Temperature

For AFDD, data can be obtained from the NOAA data or other and is sort of a net FDD. 

An example, it appears for December 8, for the Hennepin canal area, the AFDD was in the 100 to 200 range.  However, just to the south, Peoria was in the 0 to 100 range.  If we assume AFDD = 100 and treat the Hennepin as a sheltered small river, using the upper end of the range for C—as a canal, the water isn’t moving in most spots and is closer to a lake—we then can assume C = 0.4.  

Thus, with AFDD = 100 and C = 0.4, an approximate ice thickness of 4 inches is obtained, as Ti = (0.4)*(√ 100) = 4.0.  I had reports that people were out ice fishing in the area near the Hennepin Visitor Center—but this was on a lagoon, which more closely resembles a lake, thus one could assume a higher coefficient, say 0.5, there.  The actual canal was mostly frozen but I also heard that the ice may not have been as thick or solid there as in the lagoon.

This formula uses broad assumptions.  While the metrological data is going to be fairly accurate, the choice of the coefficient C involves much guesswork.  While at places the canal is somewhat like a windy lake, in others, moving water at the locks or due to a spring may make it more like a river, with a much lower value for C.  And the ice strength is also influenced by the quality and nature of the ice—white, bubble-filled ice counts for only half the strength of clear ice.   

Sure, one could blithely say that the canal is like a lake and assign a high value to the parameter C, but making assumptions about parameters in mathematical formulas (in the finance world, assumptions about parameters such as default rates, potential real estate value decline percentages, liquidity, etc.) is what those investment bankers and financial whizzes at Lehman Brothers, Bear Stearns, A.I.G., et al did when constructing their models about CDOs, CDSs, funding, and other complex financial instruments.  So, bottom line is, don’t ever be too confident in any formula, even if the formula is right it won’t matter if you are making the wrong assumptions about parameters.  TEST THE ICE ALWAYS FIRSTHAND.  We’ve already spent something like a trillion dollars because people made the wrong assumptions about parameters in formulas. 

Skating on natural ice is different than on a Zamboni'd indoor rink.  Because the ice can have bumps, ruts, and even a dusting of snow, its much easier to skate in special "nordic skates".  The blade of a nordic skate is different, and clips into a cross-country ski boot.  The blade is often even a little longer than a speedskate blade (think  Bonnie Blair-type skates), and is probably more than double the length of a hockey skate or figure skate blade.  Besides the longer length, the other advantage of a nordic skate is that it is a "tall" blade coupled with a "prow" as the front edge to cut over ruts and even a little bit of snow.  (Here's a link to buy blades: http://www.nordicskater.com/blades.html ) 

I'm hoping for good, snow free conditions on the Hennepin at some point this winter.  We are getting closer--the ice was starting to freeze in places this week from one report I had, and should start to freeze more over the weekend.  Last winter, a record of sorts was set in Chicago for bitter cold without any snow cover (I don't know the exact stat but heard about it on the Weather Channel--this was the same weather system that set in over the upper Midwest about the time of the NFC Championship game in Green Bay, WI, and not only was the Hennepin frozen but so was NY Giants coach Tom Coughlin's face). 

Ideally the ice surface will be smooth and free of ruts.  The nordic blades can deal with a little bit, but the less the ice is like an indoor rink, the slower skating becomes.  For some of the outdoor ice skating tours, the hosts typically mount a brush or plow to an ATV and smooth of the ice, but many of these tend to be 10km loops on a frozen lake rather than point-to-point.