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Flow levels reach new high

It ain't over till it's over. That memorable line uttered by Yogi Berra about a baseball game could very well translate into a comment on flood conditions that are wreaking havoc in southeast Saskatchewan.
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It ain't over till it's over.

That memorable line uttered by Yogi Berra about a baseball game could very well translate into a comment on flood conditions that are wreaking havoc in southeast Saskatchewan.

Flood waters will probably continue to race through Estevan, Roche Percee and the RM of Estevan for a few more days, testing the will and patience of hundreds of area residents who have been displaced by the prevailing sogginess.

According to Dale Hjertaas, executive director of policy and communications for the Saskatchewan Watershed Authority, the total volume of water being released from Rafferty and Boundary Dam reservoirs and running into the Souris River and onto low-lying land in and around Estevan and the RM of Estevan, is 555 to 750 cubic metres per second. That peak flow isn't expected to subside either, at least not for a few more days.

As of Monday morning, the release flow rate from Rafferty was 425 cubic metres per second while it was 130 at Boundary Dam.

"Further rain overnight on Sunday prompted the Monday hike," said Hjertaas, since there was no storage capacity left at either of these two dams.

Referring to the situation as a "major flood condition," Hjertaas said the Authority was continually monitoring the inflow to Boundary from Long Creek which may prompt a further increase from that reservoir.

The authority started releasing the current peak flow Sunday afternoon (June 19) to accommodate the additional flows upstream due to recent heavy rains that also caused major problems in communities such as Yellow Grass and Weyburn where nearby Nickle Lake had peaked to its full level.

All this means that water levels around the RM of Estevan and some city areas could rise as much as another half metre before they begin to subside. And if rains come again within the next few days, then all bets are off and the water control experts head back to their drawing boards and calculators.

Things are a little less desperate at the Alameda Dam where water release had to be upped from 27 cubic metres per second to 50 on Monday, again, to accommodate the rain in an already full reservoir.

"We want to get some space in those reservoirs," said Hjertaas, referring to Boundary and Rafferty. That would mean a continuation of the extremely high flow rate in an attempt to lower the levels by even a few centimetres.

"So you'll be seeing some continuing high flows for a few more days and we review it every day ... every hour ... expect 555 cubic metres for a few days, there's still a lot of water coming through the system," Hjertaas said.

Hjertaas said that this almost worst case scenario came about due to the "third or fourth major rain event we've had since the reservoirs filled. The ground was already saturated, the capacity of the reservoirs is limited, so the water has to be passed through."

The Watershed Authority executive added that "Rafferty was built for a one in 100 year flood crisis, and this is it."

Without the dams, the flow through the local valley with each episode would have been about 700 cubic metres per second, or another half metre in depth over what is already being experienced.

"Our daily information sharing with the downstream recipients such as the city of Minot, informs us they are coping, but with this now ... it's going to be a large flood at Minot," Hjertaas said.

As far as dam integrity is concerned, Hjertaas assured the media that the dam structures are holding up well, they are not being breached and rumours of them having to truck in clay products to buttress a failing structure just weren't true.

"Someone may have seen trucks with material in them heading out to the region, but that would probably be for dike building in Roche Percee or somewhere in the RM," he said.

"We monitor the dams continually, there are no breaches or faults found in the structures."