News
Forty-year flashback: Big potential for drainage in Manitoba

Aug. 12, 2013 – Drainage Contractor magazine is celebrating its 40th anniversary in 2013, and we’re taking a look back at what made the headlines 40 years ago with Forty-year flashback, a series of articles from the magazine’s first few editions.

 This week’s article, published in the 1975 edition of the magazine, highlights drainage potential in Manitoba. 

In spite of large acreages of valuable agricultural land in Manitoba being plagued every year by excessive moisture, subsurface drainage is not an established agricultural practice in the province.

The drainage measures used in Manitoba are limited to improvements to existing water courses and to the construction of main drainage canals and ditches.

On-farm drainage, too, is limited to randomly built drainage ditches and can solve only part of the problems caused by excessive moisture.

Conservative estimates indicate that nearly two million acres, that is, more than 10 per cent of Manitoba’s agricultural land, suffer seriously from excessive moisture. In some highly productive areas, the percentage of land damaged periodically by excessive moisture is much higher.

Some of the difficulties can be attributed to an inadequate network of the basic system of drainage canals and ditches, which serves as a recipient for the on-farm drainage systems.

Most farmers are aware of the urgent need for effective on-farm drainage, but there have been some important circumstances which have prevented them from realizing their wishes. The main problems were economic. Farmers realized that an effective on-farm surface drainage system would cost too much if contracted, or that it would require too much of their own labour and time if they had tried to do it themselves. In addition, in an effective surface system, the network of ditches would be so dense that it would interfere with modern farming methods.

Technically, the answer could have already been found a long time ago in surface drainage. But the traditional clay or concrete tile drainage was too expensive for the grain growing prairies. It was also cheaper in Manitoba – until not too long ago – to increase production by expanding the arable land rather than by improving it at such a relatively high cost.

It was only in 1971 when subsurface drainage was really introduced to Manitoba. In July of that year, two small pilot and demonstration subsurface drainage systems were installed – one in St. Agathe, south of Winnipeg, the other in McCreary, near Riding Mountain – by a group of interested contractors and suppliers in co-operation with the Manitoba Department of Agriculture and the Agricultural Engineering Department, University of Manitoba. In both systems, perforated corrugated plastic tubing was used. It was installed partly by a trencher and partly by a trenchless plow.

The St. Agathe system has been monitored and evaluated by the Department of Agricultural Engineering, University of Manitoba, since that time. But some farmers did not wait for the results and had their own systems installed in the following two years. More than 100,000 feet of plastic subsurface drainage has been already installed in Manitoba and more will be installed in 1974.

The soils in which drainage has been installed range from medium sandy loams to heavy clay soils and one of the systems is in a peat moss soil. All have been working, especially in the extremely wet spring of 1974.

Observations from the St. Agathe system, which is in the most extreme and difficult conditions in the heavy Red River clay soil, confirm the success of the system clearly. Studies of the changes in the soil moisture (drying of the soil) have shown that in the spring of 1973 the drained area was ready for seeding at least six to eight days before the non-drained area. In the critical year of 1974, the difference was at least two weeks. In the climate of Manitoba, where the growing season is short, a two-week difference in the beginning of the spring field work means a great deal.

Photographs offer the best illustration and documentation of the benefit of subsurface drainage in St. Agathe, Manitoba. While a half-ton truck could be driven safely on the drained land, a short expedition on the non-drained land ended in a complete mess. The truck became bogged down and only a long chain and a tractor operating on the dry ground of the drained area could get it out.

Concerns that the function of the drainage in such heavy soil might decline when the soil in the trenches settles proved void. In the third year of operation, the drainage was more efficient than before, probably because of favorable changes in the soil structure.

The future outlook for plastic subsurface drainage and its potential in solving the problems caused by excessive moisture are certainly bright. If Manitoba adopts some form of financial assistance on drainage similar to other provinces – there is none at the present time in Manitoba – this potential might be realized and have a far-reaching positive impact.