Tile Drainage: a solution to excess water? Stewart Brandt Northeast Agriculture Research Foundation Melfort, SK.

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1 Tile Drainage: a solution to excess water? Stewart Brandt Northeast Agriculture Research Foundation Melfort, SK.

2 Outline Why tile drainage How it works NARF tile drainage project

3 Why Tile Drainage? Excess water regularly limits crop production Roots need oxygen to function, and saturated soil has no oxygen Potential to correct saline soil by leaching out salts

4 WATER LEVEL ELEVATION (M) ABOVE SEA LEVEL MELFORT OBSERVATION WELL : 1967: Meneley Well Depth : 35 feet : Water level now 15 feet below ground OBSERVATION WELL: MELFORT LAND LOCATION: NE W2 HYDROGRAPH OF MEDIAN MONTHLY WATER LEVELS WATER SECURITY AGENCY DATUM: M DEPTH: M YEAR Water tables are higher in NE SK than they have been in the past 50 yr Figure courtesy Les Henry OCTOBER 16, 2014Watr 4

5 Tile Drainage Effect on Crops

6 Canola and barley in saturated soil

7 Removal of excess water Increases water use by crops Increases crop growth and grain yield Increases temporary storage space in soil for water from rains or spring runoff. Reduces surface runoff and delays peak streamflow after rains. Can leach salts from saline soil. Allows more timely field operations with lower equipment costs

8 Will drained soil contribute to drought in dry cycles? Capillary rise of moisture

9 Yield Improvement With Tile Drainage Difficult to find good data: but averaged across wet and dry years % in for cereals 10-45% for corn 7-15% for soybean 10-50% for potato 100 yr models estimate average yields improved by more than 50% in N Dakota

10 Earlier start Other Benefits based on surveys in MB 1990s Reduced drown out Access for spraying and cultivation Compaction reduced Better timing and utilization of fertilizer/pesticides Decreased surface runoff

11 Where Does Tile Drainage Fit Best? High value crops Coarser textured soils Crops with low tolerance to excess water Level topography / Poor surface drainage Large amounts of surface residues Ample or excessive precipitation Seeding and harvest times are critical

12 Considering Tile Drainage?? Is the water table above level of tiles? Do I need to drain whole fields or just targeted areas? Cost is a big factor Where will the water go? Point of adequate discharge

13 Determining Water Table Peizometer wells Dutch auger; 10 of extensions; 2 PVC central vac tubing, end caps Photo courtesy Les Henry

14 Surface and subsurface soil texture affects tile spacing Soil Type Soil permeability DRAIN SPACING (FT) Good drainage Excellent drainage Drain depth Clay loam Very low Silty clay loam Low Silt loam Mod Low Loam Moderate Sandy loam Mod high

15 Tile Designs

16 Parallel most commonly used design usually the most efficient and cost-effective The header pipe is installed along the field edge (or edge of the area to be tiled) and the laterals tee in at regular intervals.

17 Targeted designed to target smaller problem areas where other parts of the field do not require drainage. Usually a main pipe will be installed and then submains and laterals branch off it. This method is best suited to rolling land or fields with springs or salinity pockets.

18 Tile Drainage Project Initiated in fall 2014 Funded by co-operating farmer, NARF, ADOPT and Shark Ag consulting 40 acre site 1 mile E of Melfort Research Farm

19 Tile Drainage Project Salinity mapping of site Tile drainage system engineered and installed 3 piezometer wells installed

20 Tile Layout Salinity Map Tile map

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22 Results to Date Water began flowing as soon as tiles installed continued past freeze up every year Water table usually below 30 on drained, but sometimes within inches of surface on undrained. Initial EC was 8000 at outlet and 9000 in the creek. Ie. creek was more saline than tile water.

23 Results continued During peak runoff creek is above drain outlet Flow increased after each rainfall event, soil was at or near field capacity above drains. Flow decreased to zero by July 20, 2015, but resumed July 27 (5.5 inch rain over 6 hr). Flow continued all of summer 2016 EC ranges from 4000 to declines after precipitation events, and increase during dry periods.

24 Oat 2013 Red = 5-50 bu/ac Yellow bu/ac Green 130+ bu/ac Wheat 2014 Red = 5-20 bu/ac Yellow = bu/ac Green = bu/ac Canola 2015 Red = bu/ac Yellow = bu/ac Green = bu/ac Barley 2016 Red = 5-50 bu/ac Yellow = bu/ac Green = bu/ac

25 Yield SUMMARY Actual yield impact difficult to estimate accurately Before drainage: oat was < 20% of well drained area of the field wheat was < 25% of well drained area of the field After drainage: Canola was > 80% of well drained area of the field (30+ bu/ac $12/bu = $360/ac) Barley was > 75% of well drained area of the field (50+ bu/ac $6.50/bu = $325/ac)

26 SUMMARY Tile drainage is permitted but requires approvals Water Security Agency Tile drainage is a long term investment Not unlike buying or clearing more land Tile drainage likely has much less detrimental impact than surface drainage Slower water discharge and increased temporary storage Less soil disruption Tile drainage requires careful planning and consideration Best to have designed professionally Payoff in as little as 3 yr

27 Acknowledgements The project was supported by the Agricultural Demonstration of Practices and Technologies (ADOPT) initiative under the Canada-Saskatchewan Growing Forward 2 bi-lateral agreement. Farmer Co-operator; Technical support from Jessica Pratchler, Stephanie Ginter, Gayelene Daqenais, Jillian Anderson, Rikki Schick Support from Mark Gordon and Braeden Syroteuk; Shark Ag consulting