Phillip Harder, research director and hydrological scientist at Croptimistic Technology, gave producers a short lesson in water use efficiency during a Saskatchewan Agriculture webinar on Feb. 19. He shared some of the science behind crop water use efficiency and the functions of plant water uptake, as well as how to use this information to make the most of available water.

The term “water use efficiency” is typically used in reference to annual crops with the measurement of bushels per acre per inch of water — but it can also be used when looking into forages and silage crops.

“Crop water use is going to be a function of how much water is being demanded by the atmosphere,” Harder says. “So, dry air is going to exert a much larger pressure gradient on water within the leaf, and so, the drier things are, the more demand there is from the atmosphere to suck that water out of the plant. And then your plant, on the other hand, is trying to resist that because it wants to maintain as much water inside through stomatal regulation.”

The stomata, located on a plant’s leaf, are the “gatekeepers.” They open and close to let in and out water and gasses that a plant needs to function. Stomata are impacted by light, temperature and humidity (also referred to as atmosphere), and soil moisture levels — which are each important for the plant to determine just how much water to take in and transpire for optimal growth.

Harder provided the example of high temperature and low humidity, which causes a very dry environment — a situation many are familiar with over the last few growing seasons. This scenario creates a lower water vapour pressure deficit that decreases stomata conductivity, leaving the gates closed to reduce water loss.

“Basically, this is the response of the plant to say, ‘Yes, the atmosphere demands more water, but I need enough water within my cells, within my leaves, so that I can still do photosynthesis.’”

However, this natural reaction to save water limits a plant’s productivity. Another influence on productivity is what Harder called the “transpiration paradox,” where in order to take in carbon dioxide to perform photosynthesis, the plant loses water vapour to the atmosphere as the stomata open. To counteract this, a steady supply of water is needed.

An adequate water supply is also important to reduce the air temperature surrounding a plant. Through the function of transpiration, a plant releases water vapour which cools the surrounding air and helps reduce the amount of energy used to grow.

“In an ideal situation, to maximize productivity, you want to be in a scenario where you have more water than can be just immediately taken up by a plant. And so, this is a well-watered situation, this is an irrigated situation.”

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“We had an extremely warm winter with lower-than-normal precipitation in most areas,” says Trevor Hadwen, agroclimate specialist for Agriculture and Agri-Food Canada. “We were a little worried going into the spring, for sure. But this has calmed us down.”

While the wet spring created difficulties in seeding in a few fields, most producers across the Prairies have their fields seeded with sufficient topsoil moisture to get the crop off to a decent start.

After years of having to adapt to drought, though, what does this shift to wetter growing conditions look like for dryland Prairie farmers?

Soil management strategies

Ken Panchuk, a provincial soils specialist for Saskatchewan’s ministry of agriculture, says for the most part, big-picture soil management strategies won’t change much for dryland farmers in his province. Strategies such as no-till and regenerative farming are widespread and excellent at managing water in dry or wet conditions.

But in a province like Manitoba, where there is a little less uniformity in soil management strategies, the situation can differ from one farm to another.

“It may depend a little bit on what the soil management strategy has been on those fields,” says Marla Riekman, a soil management specialist for Manitoba Agriculture. “If soils have good structure and haven’t been over-tilled, they may be soaking up and using some of this water a little better, because they may have an easier time infiltrating that water deeper into the soil profile.”

But producers who have structural issues, where water doesn’t move down into the soil profile as easily, may find themselves struggling with problems such as soil compaction this year.

“Now that we have a bit of moisture, the soil particles can slide over each other a little bit easier. This is where soils can be at a higher risk of things like compaction associated with field activity,” she says. “We tend to see more ponding in those compacted areas of the field.”

Obviously, avoiding field activity is impossible, but Riekman says farmers finding themselves in that position should start thinking about basic concepts for mitigating compaction.

“We want to make sure that we’re thinking about things like properly ballasted tractors, making sure our tractor tires are at their rated pressures, and making sure that we’re limiting some of the weight of the equipment where we can,” she says. And if these conditions carry into the fall, farmers should try to reduce the amount of random traffic crossing the fields with equipment such as grain carts.

Managing salinity

Riekman stresses that salinity issues don’t go away during wetter periods; they just hide.

During dry years, salinity tends to get worse because there is more evaporation than precipitation, which results in insufficient water moving down to wash the salts down into the root zone. Because of this, the water moves upward (through processes like capillary rise), bringing salts toward the surface, where they often show up visibly with that bathtub ring effect.

“Now that we’ve moved into some wetter periods, we start to see the salinity become diluted at the surface, or hidden,” Riekman says. “So we may have a temporary reprieve.”

But even in a wet cycle like this, if the rains continue and the water table rises close to the surface, the salts will rise with the water table and begin to show up again.

“Salinity is always cycling; it comes along with wet and dry periods,” Riekman says.

Paradoxically, Riekman says years like this, when the problem seemingly goes away, are often the best time to start managing salinity.

“If you have areas where you want to establish a salt-tolerant forage during those dry years, it can be very difficult; the soil is just too dry at the surface. When you have a bit of moisture, you may have better luck,” she says.

Weed control strategies

Weed control is another undertaking that changes under wetter conditions.

“Right now, producers are focused on watching the flushes of weeds coming,” Panchuk says. “When you have frequent showers, that’s a recipe for getting the next flush of weeds established.”

The big question producers and extension specialists like Panchuk will have to address is which weeds are developing and at what density, so they can determine the correct control products to use.

“Because weeds are competing for moisture and nutrients, you don’t want to let the weeds get too far advanced,” Panchuk says. “If this generous raining pattern that we have becomes a drier bias, then producers will need every drop of moisture that was conserved earlier in the growing season to bring the crop to maturity.”

The timing is also critical.

“We’ve got the longest days of the growing season upon us right now, so take every opportunity to get as much growth occurring as possible to get canopy cover,” Panchuk advises. “Once the canopy covers the field, then the crop would have a competitive edge over any new germinating weeds.”

Think about insurance

As we head into a wetter summer with high temperatures expected, farmers may also want to make sure hail insurance is updated. While this moisture is definitely a good-news story for farmers, there’s a literal black cloud attached to it: an increased risk of severe storms.

“One of the key components of getting storm events is moisture,” Hadwen says. “If we have moisture available on the surface and we get some heat, that will breed thunderstorm activity.”

The number of hail events has been relatively low during the dry years, but that appears set to change this year, he says.

“We will likely get larger and more storm events than we have had in recent years.”

Not out of the woods yet

While the moisture the Prairies have received this spring has recharged the water table, Hadwen said it’s a bit too early to declare the drought over — although that day appears close in Manitoba.

“We’re not quite out of the woods in some parts of the Prairie region,” Hadwen warns. “The rain is going to solve the immediate moisture needs, but it still takes a long time for the pastures to fully recover, and it also takes a long time for water supplies and groundwater to fully recover.”

Manitoba is a little bit different from the rest of the Prairies at this point, he adds.

“Manitoba has received the most moisture. The province received about 200 millimetres of precipitation in the central region, all the way from Winnipeg over to Brandon.”

This is typical for Manitoba, he says, because the province tends to have a wetter climate, but in recent years, southern Manitoba has been in a significant drought in terms of moisture deficit levels.

There is little concern for Manitoba in terms of moisture deficits, Hadwen says; in fact, the province has pretty much recovered. The only area of concern is the province’s northwest, which has received a little less precipitation than the rest of Manitoba.

“Last year, we had some very dry conditions compared to what we would normally get,” Hadwen says, adding that timely rains, as well as conditions cooler than the rest of the Prairies, helped.

“But this year, that 200 millimetres for that central southern portion of the province is excellent for soil moisture, though probably a little too much for some areas,” he says. “That is starting to percolate and really recharge those subsoils.”

In Saskatchewan, Hadwen says, precipitation ranged from just over 100 mm around the Regina area to a maximum of about 150 mm in the area west of Saskatoon.

But nevertheless, the drought prognosis is almost as good for Saskatchewan as it is for Manitoba, with only a small pocket in the agricultural area in the northwest with any significant drought risk.

“In that western region of the province — Kindersley, Leader, and even all the way up to the North Battleford area — it has been a little bit drier,” Hadwen says. “They’re recovering, but just not at the rate that we need. They were certainly in a much larger deficit going into the year. So we still have some concerns. But again, we’re seeing tremendous improvement.”

Most of Alberta received rainfall in the 100- to 125-mm range, and as a result, the province is a little bit worse off in terms of drought. One area that seems to be missing most of the rainfall so far is Alberta’s Peace region, but Hadwen says that region doesn’t normally get the bulk of its rain until late June or early July.

“That central region of the province has a little bit of what we call that D2, or severe drought category, and a little bit of D1, which is moderate,” Hadwen says. “But the reality is that those areas were the D3s or D4s last month, so we’ve seen improvement throughout the Prairie region.”

Unlike Manitoba, the subsoil is not fully recharged in Alberta and Saskatchewan.

“We have the moisture in that top root zone that will really get us through that spring period, but we really need moisture to percolate down and recharge levels further down,” Hadwen says. “We’re going to need continued rain this season. We don’t have those deeper moisture levels to really rely on.”

Precipitation models aren’t telling forecasters much for the coming months, he says, but there is some reason for optimism from the meteorologist maxim, “Rain begets rain and drought begets drought.”

“It’s a cyclical thing,” Hadwen says. “You need that moisture that we’ve received to break the drought. Now that we’ve got the moisture in the system, we will continue to get some big rainfall events until that moisture dries out.”

Hadwen also points to a significant moisture deficit in the three- to five-year period.

“We have fixed the moisture deficit for most regions in the one-year timeframe. But over the three-year timeframe, we’re still seeing pretty big deficits,” he says. “So we’re still not fully out of the drought.”

The post Moving from dry to wet appeared first on Grainews.

Water is considered to be the universal solvent because it is capable of dissolving more substances than any other liquid. Therefore, one of the first things we might want to know about a given water sample is the total dissolved solids (TDS).

TDS can be determined by evaporating a sample to dryness at 105 C and weighing the residue — simple in concept, but time-consuming in practice, so not often used.

TDS can also be determined by measuring all the chemical elements in a sample and adding them up, but that is seldom done. If the chemical elements are previously determined, it is a simple matter to add them up. If just TDS is reported, with no explanation of how it was determined, it may not be reliable.

What chemical elements are dissolved?

Major positively-charged elements are Ca++, Mg++ and Na+, with K+ as an also-ran. Hard water is caused by Ca++ and Mg++, while soft water is dominated by Na+.

Water hardness is expressed as CaCO3 equivalent in parts per million (p.p.m.) and can be easily measured in the field with a Hach testing kit. In our days on the road staying in motels, we could get some idea of water hardness by the way the soap acted in the shower!

• Negatively-charged elements are Cl- and SO4 – -, with NO3- as an also-ran. Most of our waters are SO4 dominated.

Electrical conductivity

Electrical conductivity (EC) is a simple measurement that can be easily made in the field. The units are microSiemens per centimetre (uS/cm), corrected to a standard temperature of 25 C.

For sulphate-dominated waters, with TDS from 1,000 to 20,000 p.p.m., a useful first approximation is that EC in uS/cm is about equal to TDS in p.p.m.

The level of water hardness in water wells is determined by the geology of that well. If completed in glacial deposits, the water will be hard. Unless completed in sand, most Saskatchewan farm wells have hard water. If completed in pre-glacial (that is, bedrock) deposits, the water will be soft. Most Alberta farm wells are completed in pre-glacial deposits, so the water is soft.

A final note

In this neck of the woods, if we know the EC and hardness of a water sample, we know a lot about that water and what it can be used for.

Many water well drillers have EC and hardness equipment with the drill rig and can measure a water sample as soon as a well is developed and pumping.

The post Water chemistry: a Coles Notes version appeared first on Grainews.

The province on May 3 issued an advisory for owners of private wells that their water “may exceed a new health-based guideline” for the trace element.

The element occurs naturally, and commonly, in well water throughout Canada. It’s often associated with discoloured (that is, brown or blackish) water, which can stain laundry and/or plumbing fixtures, and which some well owners deal with through water treatment.

Up until recently, the province said, manganese was thought to have only “aesthetic impacts” on well water.

However, the province added, based on “new evidence,” Health Canada in its 2019 Guidelines for Canadian Drinking Water Quality (GCDWQ) put a health-based “maximum acceptable concentration” of 0.12 milligrams per litre on total manganese in drinking water.

To reduce complaints of discoloured water, the federal guideline also set an “aesthetic objective” at 0.02 mg/L or lower.

Health Canada’s 2019 GCDWQ for manganese was adopted in December 2020 as the drinking water standard in Manitoba.

Manganese is an essential element and consumption of small amounts is part of a healthy diet, the province said. In solid food, manganese is “usually not a concern.”

But the new evidence indicates drinking water with high levels of manganese “may harm brain development in infants and young children,” the province said. Infants fed with formula mixed with water are considered to be “the most sensitive population.”

As the health basis for the new standards, Health Canada cited “effects on neurological development and behaviour (and) deficits in memory, attention, and motor skills.”

For adults and older children, the province said, short-term exposure to manganese in drinking water slightly above the guideline is “unlikely to cause negative health effects.”

However, the province added, long-term exposure of adults and older children to levels above the federal guideline is “not recommended.”

If manganese levels test above the maximum at the well or the tap, users of the well should either seek out an alternate water source for drinking and “all other consumptive purposes,” or install water treatment devices, either where the water enters the house or at the tap.

In its evaluation of manganese in well water, the province reviewed groundwater samples collected via regional groundwater quality surveys, its well sampling program and data collected through its regulation of public and “semi-public” water systems.

The evaluation showed naturally-occurring manganese can be found within “a wide range of concentrations” throughout the province, at “all kinds of well depths, aquifer types, and geological settings.”

It found about 56 per cent of wells sampled were above the 0.02 mg/L aesthetic objective for manganese, and 34 per cent above the 0.12 mg/L health limit.

On average, the province said, the manganese concentration per well throughout Manitoba ran at 0.5 mg/L.

At the 0.12 mg/L level, the province said, water is often discoloured and may have a “bitter, metallic taste,” but may not be apparent by taste or colour of the water in all cases. “The only way to determine manganese levels is to test the water.”

Manganese makes its way into groundwater mainly through “dissolution of naturally-occurring minerals commonly found in soil and rock,” Health Canada said, while other sources may include industrial discharge, mining activities or leaching from landfills. — Glacier FarmMedia Network

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Many areas received low rain in 2015, 2017 and 2018 but still grew good crops. Many attributed these good crops to modern farming techniques. Zero till, especially, has been a huge factor as it saves the surface moisture so a crop will germinate and emerge. But, without the soil reserve and high water tables, it would be a different story.

With recent dry years, we have seen sloughs dry up and water tables drop. On many pastures, sloughs are a major source of water. This summer I have had requests for information about establishing more wells in pastures for a more consistent water supply.

Searching for water

In many areas there is water in the ground (i.e. the water table) at a depth of 30 feet or less. The water table is the area where all soil pores are filled. The free water will enter a well such that we can extract that water by pumping. If the soil is silt or clay, water will seep to a dug or bored well and a low-yield well is possible.

To make a high-producing well, a search for water is essentially a search for sand layers. The sand layers let water go fast enough to allow pumping at a rate to supply the need.

Bored Wells

Large diameter bored wells (or, in the old days, dug) are used where the water supply is fairly shallow, about 50 feet or less. If the soil is sand over sand over sand to 30 feet or so, a shallow bored well can be high yielding. Even if the land you farm is good medium or heavy soil with a thick saturated sand layer below the soil, a high yield well is possible. Neighbours at my Dundurn farm have installed such wells in recent years with yields of 50 gallons per minute (gpm) or more.

Shallow bored wells provide the possibility of several spaced water sources in a pasture to improve grazing efficiency. Some neighbours have installed solar panels to supply power for a well pump to deliver to a large trough.

But in many situations there is no good sand layer so a seepage-type bored well might supply enough water for the need. Sometimes the well is constructed to a depth of as much as 80 feet, just to provide more “reservoir.” Even a few thin sand layers in the glacial material may be enough to provide a useful supply to a trough.

Drilled wells

Hydraulic rotary drilled wells can be to any depth. Normally a testhole(s) are dug, logged with catch samples and an elog run. The elog provides precise information on the thickness of the potential aquifer and provides information the driller needs to place the screen for maximum yield. Usually a drilled well will provide a consistent supply for many years.

In my experience, most water well contractors are a special kind of people. I have huge respect for farmers and water well drillers. Both must have many technical and management skills, the ability to adapt to what Mother Nature hands them and a generous dose of common sense.

Water well information

To determine the possibilities in your area, the first step is to gather information about existing or historic wells. Information about neighbouring wells is good, but today the number of farms is much fewer than in the past.

For readers in Saskatchewan, the “Grey Books” are a great source of archival information about water wells

Those with a copy of Henry’s Handbook of Soil and Water can check out page 152 for details. Briefly, in 1935, the feds sent out hordes of geologists and students to survey all farm water wells in much of Saskatchewan. The area included all farms from the U.S. border up to the top of Township 32 (just south of Saskatoon). In later years northwest Saskatchewan was surveyed up almost to Meadow Lake. The survey also included parts of Manitoba and Alberta but those were done later and mostly in areas larger than rural municipalities.

In 1935 there was a high density of farms in Saskatchewan so there is a huge database of groundwater, especially for shallow dug and bored wells. The data was published by RM and each RM was provided a paper copy. I am sure almost all have been tossed out. “Who needs that old stuff?” would be the thinking.

But geology does not go out of date so it is still very useful information. Paper copies exist at the University of Saskatchewan library and at the Water Security Agency in Moose Jaw. I have used those at the U of S often.

In the 1980s/90s we used the old and modern well data sources to make water well maps of much of Saskatchewan. Those have been scanned, but so far the Water Security Agency has not posted them.

Now the good news

I have recently discovered that the feds have scanned those old gems and they can be accessed online.

My most recent need was for information in Tp25 R32W1 in the RM of Calder, east of Yorkton Sask. To find that I Google: “Rural Municipality of Calder Water Supply Paper 1936.” The link you’re looking for should come up near the top. For me it is the second Google result, “Downloads — GEOSCAN search results.” Select that link and choose to download the publication.

Just substitute the name of your RM and you should be good to go.

That will give you both a map and report. The map shows 77 wells in Tp25 R32 W1. The report has a detailed description of geology, topography and well types in the Township and the Appendix Tables give detailed data for each well. Most are 40 feet or less deep and many are less than 25 feet deep.

That 1935 survey was completed in one year and all the individual RM reports were published in 1936. All that with no cell phones, email or social media. In today’s bureaucratic world it would take that long to strike the committee to determine if and how it should be done!

Alberta

This Alberta government webpage on water wells presents you with a platform that allows even old fossils like me to have a water well report in no time.

The data also includes seismic shot hole data. There is a 60-foot flowing shot hole just southwest of Youngstown. In our soil salinity days shot hole data was very useful because they went down road ditches and drilled at regular intervals so there was lots of data. If there was any a shallow aquifer that flowed they found it. A flowing shot hole meant that we knew the cause of the soil salinity in the area.

Saskatchewan

For Saskatchewan water well information, visit the Water Security Agency website. The current version works very well and in jig time you will have a PDF that gives all the details for the well(s) you are interested in.

Manitoba

Manitoba has published groundwater availability maps on a map sheet basis and are working on a digital platform at this time.

If you need better water supplies in a pasture a good look at groundwater possibilities might bear fruit and provide a reliable supply through wet years and dry.

The post Les Henry: Water information in Western Canada is flowing nicely appeared first on Grainews.

In 2007 I was involved in a hydrogeology study of a new subdivision in southeast Saskatoon. The real work was done by an engineering firm who hired a subcontractor to handle the hydrogeology part. I just helped a bit by showing what could be learned about the underground by being able to “read” what Mother Nature was telling us at the soil surface.

Elk Point Drilling of North Battleford was the drilling contractor and John Soloninko (1935 – 2017) himself was coming — a great thrill for me. I knew he would want good quality (low salt) water for drilling so I tested nearby sloughs with my trusty field electrical conductivity (EC) meter.

One pretty little slough (PLS) had very salty soil on the east end with nothing much growing. On that basis I expected it to be too salty for drilling but noted good poplar growth on all but east end. To my surprise the salt level was less than half that of the South Saskatchewan River at Saskatoon.

This PLS was a good learning experience for me. How could it have salty soil at one end and still have good fresh water in the slough? The land northwest of the slough had a very sharp drop in elevation.

Three shallow (15 foot) water table wells were installed to the northwest of the slough. The table below shows data from those wells.

The test wells started about 12 m west of the slough and were spaced about 22 m apart. In a distance of about 60 paces a lot was happening. The water level dropped by 10 feet from the slough to Well 3. The salts in the water went from 200 ppm in the slough to 2,300 ppm in Well 3. The water table had a large horizontal gradient that was the driving force allowing the water to move even in the clay soils at this site.

The slough had good water because it had an underground outlet to the northwest that allowed the water to get away and avoid buildup of salts by evaporation. When more water came in from snowmelt or rain, it quickly leaked away in the underground. Mother Nature is amazing when you understand how she works.

Why is the east end salty?

The salty soil at the east end of the slough is due to a glacial aquifer at a depth of about 100 feet that has pressure enough to push water near or above the soil surface. We knew that, so the east end salt was not the mystery. The mystery was why the slough had such good water. The aquifer ends just at the east end of PLS.

Hand-dug homesteader wells

Water was the first order of business on a homestead. Many used common sense and dug a well as near as possible to a slough. If that slough had a salt ring around it, the well was highly mineralized. Many of the salts were sulphates so no laxative required.

Well 1 had water with only 900 ppm minerals (see the table), about as good as a sand point well. Only about 45 steps away, Well 3 had 2,300 ppm. Well 3 water would be hard enough to make soap curdle and keep the stomach active. So, it is no mystery when wells almost side by each have very different water.

By July 2009 the PLS was all but obliterated by the bulldozers (see above). The poplar trees are all gone and the slough seems to be filled with topsoil.

By June 2011 the PLS was dead and buried with no evidence that it ever existed (see below). Poor little PLS.

By July 2017 the PLS was the site of fancy homes for city slickers (see photo at bottom).

The punch line

We hear a lot these days about pretty little sloughs. I almost cried about such a PLS as this being obliterated forever. Could it not have been saved and used as an outdoor laboratory for education at all levels? Not really. People have to have a place to build houses.

If the PLS had been saved and houses built all around, it would no longer function as it did anyway. The soil surface and water is linked to the soil and water beneath it. They act as a unit. To understand the surface we must understand what is beneath it. The water moving underground outside the slough boundaries is important. Underground water movement pays no attention to surface boundaries.

City slickers call sloughs wetlands and crow about all the ecosystem services (buzzword) they provide and how we must protect them at all costs. All these little sloughs must be saved and we must try to farm around them. Just as city slickers must have a place to build their houses, farmers must have land to farm.

With that, I rest my case.

The post Les Henry: A pretty little slough, a picture story appeared first on Grainews.

In this column, I’ll describe a few examples of good monitoring and show the importance of the function. I’ll also talk about some monitoring that was done in the past but is no longer available. In some cases, measurement may be happening but accessing the data is a nightmare.

Groundwater observation well data

Knowing the height of the water table over time is important because many farm folks rely on groundwater for domestic and livestock use.

The drought of the 1930s spawned the best and most comprehensive water well survey ever done in the three Prairie provinces. The survey was done in 1935 and individual RM reports (Grey Books) were available the next year. Today it would take longer than that to form the committee to decide if it should be done! Those who have a copy of my book, Henry’s Handbook of Soils and Water can check out page 152 for more information.

The worry at that time was that shallow dug and bored wells were going dry, and the feds wanted to get a better handle on the problem. In 1935 there were many, many populated farms so the density of data is high. For shallow wells, the level at that time represents a low point. We now know that water table fluctuations can be as much as eight feet over time.

Long-term groundwater observation

All three Prairie provinces have long-term observation wells. The Saskatchewan Network was sited based on locations that would reflect how Mother Nature was operating without the confounding effect of groundwater wells and pumping. The network was established in the 1960s by Bill Meneley (1933 – 2000) who was with the Saskatchewan Research Council at the time. Groundwater work, including the well data, is now at the Water Security Agency at Moose Jaw and all data can be obtained at online on the Observation Well Network page on the Water Security Agency website.

The chart below shows a continuous water level record for a 35-foot well near Melfort, Sask. Regular readers will recognize that this is an updated version from an article in 2016.

There is a continuous record of the water level from 1968 to 2018. I interpret the slow but continuous water level drop from 1975 to 2005 as a 30-year net cumulative drought with slight upticks in 1985 and 1995. We still grew crops in those years but most years the next rain was needed soon.

The big swing in 2005 was driven by the huge snowmelt that year. The leveling off in 2011 means that the excess water coming in could dissipate, likely by causing soil salinity in the area.

I recently received a communication from former student Majorie Mann. She reminded me: “I recall a speech by Tim Ball, formerly meteorologist writing for Country Guide, predicting at the peak of the 2002 drought that given sun spot science we were in for a 15- to 20-year wet cycle beginning in 2005 and he has been spot on.”

Those of you that remember Tim Ball from talks at farm meetings can learn more at drtimball.com. Tim was a professor of climate science at the University of Winnipeg, and well known for dealing with climate facts. He spent much time studying the detailed weather records kept by the Hudson Bay Company and could quote chapter and verse to show that weather some global warmers think is “new” all happened hundreds of years ago.

Surface water quality monitoring

Information about water flows of rivers and streams and lake water levels is readily available with a Google search of water survey of Canada real-time hydrometric data.

But, information on water chemistry and quality is a different matter. In decades gone by the federal government, provincial governments and Prairie Provinces Water Board had an excellent program of sampling rivers etc. and the results were published in annual data books. The data included the major minerals and in some cases herbicides as well. I still have a shelf full of those books but they are now decades old and more recent data is not available.

The records from the three rivers that become the South Saskatchewan at the Alberta/Saskatchewan border had very good records showing that the phosphorus input had actually declined over many years. The reason was that Calgary and Lethbridge installed tertiary sewage treatment that removed the major source of phosphorus.

Some measurements are still being made but public access to data is almost nil. How can we know what effect mankind is having on waterways if there is no consistent monitoring? In today’s world it should all be accessible with a few mouse clicks.

A simple example: Slough water

The table below shows data from a 12-year monitoring of salt content of a slough next to my farm yard on NW-22-32-3-W3, near Dundurn, Sask. The EC (Electrical Conductivity) is a measure of the electric current that passes through the water. The more salts, the higher the EC. EC for these waters is very close to the TDS (total dissolved solids) in ppm.

At the turn of the century that slough was dry and hay was cut. The cumulative net drought from 1975 to 2004 had lowered water tables and the water pressure in deeper aquifers that cause much of our soil salinity. The big snow of 2005 filled the slough and in June 2006 the water quality was fine for cows and could be used in some irrigation scenarios.

The continuous wet years actually made the water more salty. The salt ring around the slough and groundwater discharge would be the reason for higher salt with higher water level. For 2013 to 2015 the readings were in the 2,500 to 3,500 range.

The droughts of the past two years have brought big changes even over short time periods. In 2018 the water has gone from 3,750 on May 28 to 6,650 on July 30. The only decent rains in that time period were 0.75 inches on July 1 and 0.85 inches on July 4, both with little runoff. There have also been many days of 30 C temperatures and winds to suck up water.

Monitoring is really important and anyone with cows on pasture should be doing that monitoring or hiring it done.

Monitoring is often seen as an expensive exercise only good for academics. If we do not keep track of changes over time, how can we make proper decisions? In today’s digital world “big data: can do this but all the numbers gathered must be interpreted and placed in context to be useful in decision making.

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In the 1980s we were busy chasing soil salinity all over Saskatchewan. One area we looked at was the Consul area in deep southwest Saskatchewan. Blair Bachman had been a student and colleague at the University of Saskatchewan, so we spent some time with him to learn about the area. Blair farmed big and was one of those farmers that had a habit of asking tough questions that we had no answer for.

We were scouting one of his fields in spring and I was proudly showing him how our fancy soil probe (Backsaver) worked to determine the depth of moist soil and what that would mean for the current crop. When I found a place where the moist soil went down about three feet I remarked that it would not take much more rain for the surface moisture to join up with the “other” moisture and then he would be good to go.

His very quick response was “What other moisture?” We had our fancy auger rig that would go to 75 feet so had no trouble answering that question. That summer we went to one his summerfallow fields and went searching for the “other” moisture. Guess what? Blair was right. The water table was very deep (I do not remember the exact figure) and on much of his farmland there was likely little connection with the “other” moisture.

Also as part of the soil salinity program we made water well maps for much of the agricultural area of Saskatchewan. These are the only maps of water wells that exist. We had “discovered” the Water Supply Papers that were available for all of Saskatchewan except the northeast. Some areas of Manitoba and Alberta were also surveyed. There was a Water Supply Paper for each rural municipality. These are called the Grey Books. (Henry’s Handbook of Soil and Water tells the complete story of the Grey Books — it’s on page 152 if you have a copy.)

Water well survey

The data for the Grey Books came from a water well survey conducted in 1935 by the Geologic Survey of Canada. 1935 was the middle of the Dirty 30s. Shallow wells were going dry and the feds wanted to get a handle on how bad it was. It was a grand piece of work.

The unique thing about that survey was the density of information — there were many farms in 1935. That was why we prepared the maps. I’ve included a small part of the map west of Milden, where I was raised.

This map shows water wells in Tp 29 R13W3. This is the clay belt. There are no shallow dug or bored wells so there is no near surface water table. I’m not sure about the well on Section 22 — it’s probably in a slough. The question mark is mine.

All wells are deep and the water is a long way down. That means that it is strictly a top-down situation and there is not much help coming from underneath. It is also easy to see that without including the 1935 survey there is not much to map. There are only two wells shown on this map that were dug after the 1935 survey.

In hindsight, if we were to do the soil survey again it should be possible to map the “other moisture” possibilities. With the modern soil maps and with the water well maps and other groundwater information it might be possible, but who is going to do it?

In the meantime, if you would like to peruse the water well map for your area, the good news is that the maps have been scanned and are housed at the Water Security Agency in Moose Jaw. They are not yet on the www.wsask.ca website but a map for you area (if made) will be dispatched by email upon request.

The Water Security Agency website describes the maps and also alerts folks to the limitations of the maps.

To get a copy of the map for your area, make your request by calling 306-694-3900 or emailing groundwater@wsask.ca.

If they get enough request for maps, the maps will be placed on the website.

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Researchers Jaivime Evaristo and Dr. Jeffrey McDonnell of from the U. of S. and Scott Jasechko of the University of Calgary have taken a new look at the hydrological cycle, something that’s been pretty well established in science for some time.

“We all learn in Grade 10 about the hydrological cycle,” McDonnell said in a telephone interview. “The idea that water evaporates from the earth’s surface, it forms clouds, the water stays in the atmosphere on average a week or so globally, and then that comes back to earth as rain or snowfall, and water then goes into the ground, or runs off into streams, and the cycle keeps going around and around.”

How swiftly and intensely that cycle circulates depends on the location in the world. “If you’re in the tropics, it’s usually a very fast, intensive cycle, and then in a place like Saskatchewan, it’s a less intense cycle. Water gets locked up in snow and frozen soil, and it’s released slowly. But everywhere on earth that cycle, we thought, is one that’s ‘what goes up comes down, and what comes down ultimately leaves the system in the same way.’”

In that framework “when the precipitation went into the ground, we thought of it going into one big tank, reservoir or bucket.” That soil water would be water for agriculture and plants, and then what didn’t plants use would go into groundwater —streams, lakes, and the oceans.

A new view

The new research, though, suggests something a little bit different happens when the water is in the soil, underground. It looks as though there is a compartmentalization of part of the hydrological cycle, where water is being split up into a couple of different pools, says McDonnell. “What we found is that some water that goes into the ground goes into one pool — that bucket of water — and that water is almost stuck in the system.

“That’s the water the plants seem to be interested in using. The water that’s more mobile, and goes down and recharges groundwater gets into the stream flow, that water doesn’t seem to be connected to the water that our plants are extracting.”

The findings are the first on a global scale that support the “two water world hypothesis” — the idea that there is “a plant water world and a more mobile water world for groundwater and stream flow.”

This all seems a bit mind-boggling considering that all water is H2O. But as McDonnell says, “it’s all H2O, but I can say something about what type of H and what type of O using isotope fingerprinting techniques (the chemical fingerprint of the water).” This work also seems tied to the characteristics of the soil underground, considering that the two water worlds are both under the earth in similar ways. It’s not that the water plants use is closer to the earth’s surface and that groundwater is further underground, rather the different chemical compositions of the water interact with the soil — which has particular qualities too. Some soil is “really tightly bound” and that soil seems to be carrying the water that plants use, while soil that has “bigger pores — which might be, at the extreme, decayed root channels or an animal burrow” that’s the water that feeds into streams and the like. That water doesn’t seem interesting to plants. All of this adds up to a major rethinking of how water cycles.

Research in practice

This new study could affect farmers’ watering practices down the road. “One thing that we’ve found is that crops also seem to partition their water, like we’re seeing in forests and the like,” says McDonnell.

McDonnell says Chinese researchers who have looked at the “two water world” idea in corn fields had similar findings: the corn fields were “using water tightly bound in the soil, while the water that was in the streams and in groundwater looked very different from the water the corn was using.”

Because agricultural crops seem to be following the same new rules, further research could help rethink irrigation practices on farmers’ fields. “How we irrigate, the intensity, the magnitude, and how we think about irrigation water — which is kind of like rainfall” are all questions that could come up later on in research, ultimately allowing farmers to maximize irrigation.

Earth’s system is complicated. McDonnell says, “there are just so many things we don’t understand. This is a very small example of something we thought we understood, but with new techniques we’ve realized that we need to write a new chapter on the hydrological cycle.”

With droughts making the news all summer long, and water crises around the world, this new finding could really have positive implications on “the precious resource we call water,” says McDonnell. “Knowledge is power and it’s pretty tough to manage a resource if you don’t know how it works.”

Dilia Narduzzi is a freelance writer in Dundas, Ont.

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