High salinity levels may hurt farming in the Lower Mainland

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      A Richmond agrologist believes climate change is affecting salt levels in Fraser River waters needed to irrigate crops.

      “Runoff is concentrating so heavily in the spring now because of climate change,” Arzeena Hamir, coordinator of the Richmond Food Security Society, told the Georgia Straight. “The melt is happening so early and so fast that—come later in the summer, as the river levels are starting to go down—what they call a ”˜salt wedge’ is starting to come up the Fraser River.”

      Hamir, a lifelong Richmond resident, is trying to get more farmers growing in her municipality, mainly through her role on the board of directors of the nonprofit Richmond Fruit Tree Sharing Project. She said she started hearing about higher salinity levels in the river water two years ago.

      Salinity doesn’t affect traditional crops that don’t require irrigation, such as potatoes, she said, but there’s a long-term economic implication: a higher level of salt would restrict the type and variety of crops grown and would hit the bottom lines of new farmers in the region.

      “If we’re trying to get young people back into farming, these [non-irrigation crops] are not the crops that they are interested in, because they are extremely low-value,” Hamir said in a phone interview. “Potatoes are, like, 29 cents a pound, and the same with squash. The return is very low.”

      Young people want to grow the “high-value salad crops”, Hamir said, because there is a greater return there, especially with the proliferation of farmers markets.

      “And for that, you definitely need irrigation, and so again, the conundrum is there: if you want young people back in farming, they need access to water because the type of farming they want to do is fairly highly water-intensive.”

      In his staff report on salt intrusion into the Fraser River dated July 5, 2010, Richmond’s engineering director, John Irving, noted: “The tidal fluctuations at the mouth of the Fraser River are considered large and have significant influence on the salt wedge intrusion, particularly during low flow periods in the Fraser River.”

      He wrote that only one of three Fraser pumping stations that transfer irrigation water to Richmond ditches is affected by saltwater intrusion at that time, but that it has a salinity detector that will close water access if the concentration is too high.

      Irving told the Straight by phone that city crews have set the detector at the No. 6 Road pumping station to a salinity level of 500 microsiemens per centimetre.

      “Salt sensitivity in crops starts out at around 700 microsiemens,” Irving said. “We shut it off at 500.”

      In his report, Irving wrote that “long-term projections of sea level rise” of between 0.35 metres and 1.2 metres “will have significant impacts on salt wedge penetration”. He noted that “Richmond permits drinking water to be used for agricultural purposes but does not offer a discounted water rate for this use.”

      Robert Gonzalez, general manager of engineering and public works for the City of Richmond, told the Straight that “climate change and climate-change adaptation” are topics he and his staff keep at the “forefront”. Gonzalez said the city has invested significantly, starting in 2005, in drainage and irrigation in East Richmond. He said maintaining long-term viable agriculture is important for the city.

      Veteran city councillor and farmer Harold Steves said he brought the issue of salt levels to the attention of council after a local farmer, Harry Hogler, noticed higher salinity in Fraser River water last year.

      “We’ve always had salinity, but we have never had it as bad as this,” Steves told the Straight by phone.

      Steves said he has a ranch in Cache Creek, near the Thompson River, a major tributary of the Fraser. He said the early runoff there reflects that of the larger river downstream. “We used to have enough drinking water for the house all year round, but now we don’t have a glass of water to drink by the middle of June, let alone to irrigate our fields.”

      People are ignoring the impacts of climate change, Steves claimed.

      “No matter how much you tell people it’s happening, they find a way of putting the blinkers on,” he said. “Well, when the blinkers come off, they’re going to be shocked. That’s the problem.”

      Gonzalez said 40 percent of Richmond’s landmass is used as agricultural land.

      “From this perspective, ensuring the long-term viability of our drainage and irrigation system for agriculture is one of our key priorities, one of our key initiatives, particularly for keeping farming viable long-term,” he explained.

      Hamir said a first step would entail Richmond city planners sitting down with the provincial agriculture ministry “to discuss what the potential impacts might be [of changing salt levels] and how we could go about addressing these”.

      Agriculture ministry staff did not grant the Straight an interview with Minister Ben Stewart.



      paul magnus

      Feb 10, 2011 at 11:44am

      so what are the historic and current levels? And the actual frequency of intrusion.
      These facts are missing from the story....