Wednesday, February 17, 2010

Volly Day 14, Feb 17: How to make concrete from snow

While Lindsay Vonn and Julie Mancuso made minced meat of their competition in the women's downhill, we were busy preparing men's track for SuperG Feb 19, and Super Combined Feb 21. Although the ski packing done yesterday made for a smooth surface, it was far from hard, and did not stick to hard undersurface, so there was a major water injection program. Not many "volunteers" but hey, why not try something new, so I held onto the hose as others descended with the water bars (see pics below). On the steep pitches, the weight of the very long hoses tends to make the hoses slide down the hill which could be catastrophic as: (1) it could rip itself from the hydrant (the hydrants are the outlets for water for snow making), and even rip off the hydrant attachment which would result in complete flooding and destruction of the track, and (2) it could hit or yank workers down the hill. And believe me, it was hard workholding on. We are all wearing crampons to keep from slipping, especially on steep pitches. These take getting used to, and any false step can result in tumble down a pitch, and if foot sticks in snow and rest of body keeps going, well, no need to provide more details. Another important warning we got was to be careful not to step on hose with crampons. However two people did so, including one who was giving directions. That meant shutting off water, removing the section of leaking hose, and restarting. As per pics below, we literally inched our way down from the men's super G start down three pitches and 2 flats, taking a good 3-4 hours.

Early to bed tonight as 6:30 AM upload. I suspect not much to do tomorrow, except to watch the Chinese Downhill (tune in tomorrow to find out waht this is!).

Three water bars joined by connecting hoses. Workers hold the handles and use them to move the bars down the hill, on command of leader. The bar is held in same place anywhere from 3-4 to 8-9 seconds depending on water pressure, how deep the water needs to penetrate, and how much water is needed. A little bit of science and a lot of old-fashioned experience.

Loops of fireman's hose connecting hydrant to the bars. The blue cord you see is used to loop around the hose and hold it from sliding down the hill. Workers holding the hoses are separated by 10 to 30 or more yards depending on how steep the hill is and how difficult it is to keep hose from sliding.

Close-up of water bar showing water coming out of nozzles under high pressure. The nozzles are about 4 inches apart. Before the water hydrant is turned on, the nozzles cannot touch the snow surface or they will get blocked up, rendering them useless.

Close-up of holes left after water injection. Each row shows holes about 4 inches apart (nozzle separation), and, in this picture, the two rows of holes are only 9-10 inches apart. You do the calculation of how many rows are needed to cover the entire track, 10 inches at a time!

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