By Clare Ogilvie
The provincial government is considering building a permanent debris catching structure near the site of the Fitzsimmons landslip.
The concrete and steel grate could span the creek, horizontal to an area close to Parking Lot 7 on Blackcomb Mountain, said the Resort Municipality of Whistler’s top engineer Brian Barnett.
“That’s the preferred location,” he said.
The idea is part of an on-going study into the Fitzsimmons landslip being done by EBA Engineering on behalf of the provincial government.
A report by the same company last year found that if the slump collapsed it could dam the creek. Pressure would build behind the temporary dam until it burst, releasing up to one million cubic metres of earth and debris, which would pose a threat to the village. However, the report found it was unlikely the whole slump would let go.
The slump has been moving steadily over the last few years, although Barnett said it has moved only a few millimetres in recent months thanks to the long dry spell.
For decades the resort has lived under the shadow of a
potential slide from an area on Whistler Mountain that is roughly the size of
seven football fields, 35 metres thick with rock and soil. It is about 2.5
kilometres above the village. In the spring of 2005 the province decided to
investigate the slump and all of the reports done on the natural hazard.
The recent EBA report, said Barnett, gives a rough cost of $7 million for the permanent debris flow structure. There is a similar one on Whistler Mountain above Creekside.
Barnett said the municipality would like to marry the construction of a sediment basin with a permanent debris catcher.
“The municipality is required to remove gravel build-up in Fitzsimmons Creek for flood protection measures,” he said. “We have to get approvals from the Ministry of the Environment and Fisheries and Oceans for that and they have expressed concerns about the disruption to fisheries habitat when that work takes place. So we have considered their concerns and recognized that a potential way to reduce the environmental impact is to have a sediment basin.
“That way we collect the sediment in one centralized spot and we don’t have to have as much disruption to the fisheries habitat down stream.”
Both the municipality and provincial government officials discussed the idea of integrating the two projects over the summer, said Barnett.
The revised EBA report, which contains both projects, should be completed in the next few months.
“It looks like there is a potential there to have coordinated projects,” said Barnett.
It’s likely that some gravel removal from the Fitzsimmons would still have to take place, said Barnett. But it would be much less than is done currently.
If the recommendations in the EBA report are accepted by both the municipality and the province construction could get started as early as next summer.