Disturbingly low water levels in B.C. lake and rivers may signal drought to come, say expertsSnowmelt and spring rain could turn around a situation that looks ominous with many B.C. lakes and rivers at unusually low levels for this time of year
Author of the article:Glenda Luymes
Published Apr 05, 2023 • Last updated 13 hours ago
Low water levels have created “acres and acres” of sandy beach at Harrison Lake, while boaters have begun marking new hazards that are now uncovered in the shallow water.
Harrison is one of several B.C. lakes and rivers with “much below normal” water flows compared to historical averages for early April, according to Water Survey of Canada data.
While snowmelt and spring rain could quickly turn around a trend that is looking increasingly ominous, there are signs B.C. could continue to see unusual weather and possibly drought in the months to come, with implications for forests, fish and farms.
In a statement, the Ministry of Forests said conditions in the fall and winter “set up extremely low river levels in many regions of the province.” The dry conditions, along with a lower snowpack in some regions, could impact B.C.’s “long-range drought outlook.”
“In areas, groundwater recharge has been reduced and may lead to lingering or longer-term drought implication into the summer, depending on spring (and) summer weather,” said the statement.
On the North America WaterWatch map, which codes river flows using a series of coloured dots, high flows are represented in various shades of blue while low flows are represented in red hues. On Wednesday, most of B.C. was speckled red, brown and orange, with the majority of the province’s rivers flowing “much below normal.”
“It does not bode well for the fish populations,” said Marvin Rosenau, a fisheries and ecosystems instructor at BCIT. “One has to wonder about these current wild swings in highs and lows, whether it is temperature or stream flows.”
Rosenau said low water last fall, when much of B.C. was in the grip of drought, decreased salmon habitat during spawning season. Sustained low levels through the winter and spring could “dewater” some nests and reduce fish populations.
Salmon are also a concern for B.C. Hydro as several of its 36 reservoirs contain less water than normal.
The low levels are a result of high electricity demand due to the cold weather, as well as less water storage during last year’s drought and dry conditions over the winter, said spokesman Kevin Aquino.
“March has been dry and cold across the province,” he said. “This has — and will — continue to result in lower inflows from snowmelt to reservoirs. Because of low inflows, some facilities may need lower than normal, but sustainable, target fisheries flows now and through the summer period.”
Aquino said B.C. benefits from an “integrated, provincial electricity system” that’s able to send power across the province to meet customer needs when water levels are low in some areas.
The April 1 snow conditions commentary released Monday by the provincial River Forecast Centre notes temperatures across B.C. were colder than normal in March, while the snowpack is at about 89 per cent of average for this time of year. The cool weather is likely delaying the snowmelt.
The snowpack “mirrors” B.C. winter weather conditions, said Environment Canada meteorologist Armel Castellan. Both December and January were abnormally dry across most of the province, but a series of winter storms brought rain and snow in February.
While that may have caused the snowpack to catch up to average levels, conditions have been far from typical.
“Fall was very short and then it got really, really cold,” said Castellan. “You had snow on a dry landscape as opposed to the slower switch into rain.”
Climate change is contributing to bigger swings in weather, from heat and drought to rain and snow storms, with increasingly intense and frequent weather events predicted in the future. B.C. has already seen some small early-season wildfires, including one near Merritt last week.
On southern Vancouver Island, which experienced drought conditions last fall, farmer Bryce Rashleigh has been able to plant his crops on schedule, including various grasses.
“There is adequate moisture in the ground here,” he said. “What really affects me is what happens from now until August.”
But he said farmers in other parts of B.C. may be concerned about dry soil conditions. “If you start with a deficit and you don’t get more….”
As usual, Metro Vancouver Stage 1 watering regulations will come into effect May 1, with the region’s three water reservoirs “looking good on our end,” said Heidi Walsh, director of watersheds and environment.
The region’s snowpack is about 80 per cent of normal, with plans in a few weeks to start storing some of that water for summer needs.
“It’s a balancing act for us,” said Walsh, adding the regional district looks at water needs and snow conditions across the region as it makes decisions about how much water to save up for drier seasons.
Across social media, people have been posting pictures of lakes and rivers at lows not seen in recent years.
John Allen, an amateur geologist, said Harrison Lake is about 15 centimetres above its lowest recorded level. It is typically lower in winter than summer as the Fraser River, which is connected to Harrison Lake through the Harrison River, “sucks down” the lake when river levels are low.
About 20 years ago, low water on Harrison Lake was more common, said Allen, who has lived in Harrison Hot Springs for 43 years and spent four terms as mayor. Over the last two decades, a rapid accumulation of gravel raised the bed of the Fraser River near its confluence with the Harrison River, leading to higher lake levels.
“Now that the gravel glut has washed through, the river is flowing deeper in its channel and we’re seeing the result,” he said.
Chilliwack helicopter pilot Ralph van Woerden said he’s seeing more sand and gravel bars than ever before in the Fraser River and its tributaries.
“I guess time will tell what happens,” he said.https://vancouversun.com/news/local-news/disturbingly-low-water-levels-bc-lake-rivers-unusual-weather-observers?mc_cid=1358ec065e&mc_eid=30488675cb