Intermediate Points

Intermediate Points

Intermediate points can be very handy when a course is subject to annual change. Use of them is more accurate than is the “measure the old route, measure the new route, calculate the difference” method. This is especially true after several changes have been made. After a while the changes get confusing.

I’ve been the AIMS/IAAF course validator for the London Marathon since 1987. The course has only rarely been exactly the same from year to year. A complete remeasurement of the course, done in one ride, is very difficult because of the heavy London traffic. Hugh Jones and I have overcome the problem by using intermediate reference points.

Hugh is the on-site measurer who does all the heavy lifting. He is in constant contact with the organizers, and measures any changes to the route. He has established a series of 30 or so reference points. Each point is located at a fixed landmark, such as a numbered lamppole, a storm drain, of the curbline of a road crossing the course. Over the years I have checked the measurements of the distances between these reference points.

When the course changes, the pieces of the course that are no longer in use are discarded, and a new route between previous reference points is measured. The start line is adjusted to make the distance come out right. A lightpole near the start line is our fixed reference point, and the actual start is always within a few meters of this pole.

Use of reference points places a great demand on both the measurer and the certifier. When I am the certifier, I want to see complete measurement information for each and every segment of the course. This will include calibration course documentation and measurement documentation. I will not accept applications that want me to “look at last year’s paperwork.”

The London course has segments that have been measured over six or seven years, using different calibration courses. All the checking data is kept in a single Excel file. Each year Hugh revises his report of the measurements and I enter the new data in my check file. After I check the changed segments I record my own data in the file. In this way all the measurement data is kept intact.

A single-line sketch showing the various reference points is needed so that I can understand what is being submitted to me.

The reference points do not need to be shown in the certification map, although they can be. That map describes the course itself, not its measurement. Also, showing those points takes up valuable space on the map, and the points are not used in any way by either runners or race organizers.

Using reference points requires good communication between measurer and certifier. It also requires generous time for review. It is often difficult to get one’s head around another person’s thinking.

Thanks for the quick reply and the info. As I understand it, we need to measure the new segment, between established points (just like a separate race course). Measure the corrected segment (in this case the start/finish segment). Put the cal sheets and measurement data sheets for all course segments in a package, with a new map and a single line sketch and an explanation for the certifier.

That's about it, at least if I was your certifier. If you do a good job of explaining, the certifier should understand. If they don't understand, a bit of back-and-forth may be needed.

Each segment should be measured as if it was a separate race course (shorter measured length etc). The segments, plus or minus a final adjustment, should add up to the certified length.

It's pretty much the same as if the course was measured on three or four separate days, except the days could be separated by a year or more.

Pete,

If intermediate measurements are used to build a course in the US, would the USATF course certificate expire 10 years from the year of the measurement of the earliest segment (rather than 10 years from the submission date?) -- Just curious. -- Justin

As far as I know this has not yet been determined. My own view is that any measurement, no matter how old, should have immortality as long as it has been under the observation of the original measurer.

I recognize that this can pose administrative problems.

I have a calibration course on my street that is 20 years old. I recently remeasured it and recertified it, but considered this to be overkill, as nothing had changed. Repaving had occurred, but the end point landmarks (curb joints) were not affected.

I believe the key to this is the personal oversight of the original measurer. No delegating.

I recognize that I am not the RRTC Chairman, nor officer, and that I consider my views to be individual opinions only. I am perfectly willing to go along with whatever may be decided on the subject.

This will be a discussion at the convention, however I feel the same as Pete expressed. That is, if the person doing the adjusting is the original measurer then it's OK to make an adjustment using Intermediate points. He(she)knows this course best and we at RRTC will go with this for now.

Also, as Justin asks about the certificate being 10 years from what date. It should be 10 years from the date of issue. That is 10 years from any adjustment.