Observations Regarding Impacts of Tile Drainage in Southern Manitoba - An Engineer's Perspective

Observations on Tile Drainage in Southern Manitoba
B r u c e S h e w f e l t , M s c . , P. E n g .
PBS Water Engineering Ltd.
Outline …..
• Brief history of tile in Manitoba and
current situation
• Design principles
• Value added tools for Professionals
• Sustainability elements (e.g. BMPs)
• Brief case histories in application of
tools
2
What is tile drainage?
• corrugated HDPE perforated pipe w/wo a filter sock (silt)
• installed at 2 to 4 foot depth (typical)
• lowers water table
3
Factors that Impact Soil Moisture, GWT and Tile Flow
Courtesy of Stantec
4
Self Propelled vs. Pull Type
Situation Analysis -Southern Manitoba
• Expanding tile drainage activity in Manitoba
– 6 commercial tile machines 2013 + self installation
– tile plants – 4 in MB and ND
– 10,000 – 15,000 + acres per year ?
• North Dakota and Minnesota activity
– similar rate of growth;
• Research
– Mainly BMPs oriented
– NDSU, SDSU, ISU, U of Minnesota, U of Manitoba
• BMP Adoption --- Mainly USA !
– NRCS – USDA funding BMPs
– ADMC (Ag Drainage Management Coalition)
• Controlled Drainage and Subirrigation
• Saturated Buffers
• Bioreactors
Brief Retrospective
1960s ---- Morden Research Station
1970’s 80’s --- Almassippi Wet Sands Studies
1990’s --- Manitoba Corn Growers Association
2000’s --- Research and Demonstration (BMPs)
Morden Research Station - Then and Now
1965 Detailed Soil Survey – Michalyna
Water table < 4 feet in spring
Saline sub-soils noted
Clay Tile installed 1966
Deep (4-5’) and Wide Space
2013 Soils Report - Stantec (1:5000)
New Technology (Veris)
Saline sub-soils mapped
HDPE Tile installed 2013
Shallow (2.5 -3’) and
Narrow Space
Salinity Reclaim Possible ?
Stantec Soil Survey 1:5000
Relationship of Drainage to Soils and Deep Veris
Wet Sands Research –ID Engineering (1983) Report
• Drainage research
targets 300,000 ha
• Landscape impacts (i.e.
depth to GWT)
• Crop water use from
shallow groundwater
“very important”
• Shallow tile 76 cm
recommended
Project 408: Almassippi Wet
Sands Management Project
Impact of Drainage Depth and Upflow
On Water Table and Water Use
Evapotranspiration
from shallow ground
water by cotton as
affected by soil and
water table depth
(after Grismer and
Gates, 1988)
North Dakota Research on Shallow Water Table
Follett et al. , 1974 – Effect Water Table Depth on Crop Yields
12
Manitoba Corn Growers Association
Pilot Project – 1994 to 1997
4 sites (clay loam to sand) evaluated
• drainage effectiveness
• environmental impact
Professional Input
geologist
pedologist
agronomist
hydrologist
ag engineer
tile company (Ontario)
geotechnical engineer (filter)
SITE A – Random
27 Acres Impacted
Loamy Sand over Clay
Spacing Random
(low areas)
Spring vs. Summer ! - 1995
115 acre –inches
¼ “ Drainage Coefficient
15
Producer Results 1990s – Anecdotal
Largest Tiled Farm Reported Benefits
• BENEFITS SEEN !
– Earlier start
– Reduced drown out
– Access for spraying and
cultivation
– Compaction reduced
– HOPE for salinity reduction
– PROBABLY better fertilizer
utilization and timing
– Decreased surface runoff
Yield gains (verbally reported):
• 20% corn
• 10-50% potato !
• 20 % wheat
NOW growing beans/ potatoes on
fields not grown before because of
risk of drown out
EM 38 Horizontal ….
16 years after tile drainage reduction salinity
17
2009 – 2012 Manitoba Research and Demonstration
Hespler Farms and CMCDC Winkler
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Tile Drainage and Irrigation of Potatoes and Corn
Published – U of Manitoba
Water Balance, Demand and Yield Response
DRAINMOD Modelling of Fine Sandy Loam
Ongoing Work AT CMCDC (Dr. Ranjan)
Kelburn Farms - Heavy Clay
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Clay (40-60%) Soils
Flow/Soil Moisture
Two drain spacings
No published data
Kroeker Farms – Water Footprint Monitoring
•
No published data
Total Precipitation = 332 mm
Total Flow = 71 mm
Flow-FDIR-B3-2011
FDIR-B3
Precipitation
Irrigation
0
14
Drainage Flow (mm)
12
20
10
30
8
40
¼ Inch Per Day DC
6
50
4
60
2
70
0
80
6-May-11
5-Jun-11
5-Jul-11
4-Aug-11
3-Sep-11
3-Oct-11
Recharge (mm)
10
2-Nov-11
19
Variation in ETc and Water Table – CMCDC 2012
Monitoring Tools --- Field 747 --- FarmsWater Table and
Soil Moisture Monitoring
21
Water Footprint - 2012
22
Drainage (and Irrigation) BMPs – Professional Input
Water Recycling
Controlled Drainage and Subirrigation
Nutrient Management
Cover Crops
Tillage
VRI Irrigation
Water Recycling … 200?
How to Do it: Control “Zones” – Control Water Table !
Target:
20 acres/structure
Water Control
Structure
25
Impact of BMP – Nutrient Management
Reduced GWT Nitrate = Reduced Tile Nitrate ?
CMCDC Groundwater
Nitrate-N (ppm)
Nitrate N ppm
120.0
100.0
80.0
Fall 2011
60.0
Fall 2012
40.0
June 2013
Fall 2013
20.0
0.0
A1-1
A1-2
A1-3
A1-4
A1-5
A1-6
West SB
BIOREACTOR BMP – Nitrate N Reduction in Water
• Wood chip bioreactors
• Proven Nitrate – N
reduction
• Potential P reduction
being examined
• None in Manitoba
• Iowa and Illinois are
leaders
• Concern is impact on
drinking water and Gulf
of Mexico
27
Design Principles
Spacing and Depth vs. Tile Response
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Hooghoudt Equation - 1963 (steady state)
Kirkham Equation - 1957 (preferential flow)
Control water table depth (H)
Influenced by depth to restrictive layer (D)
Spacing of tiles is computed (S)
Drainage Coefficient (DC)
28
Design Principles
Critical Input to Equations
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Soil layers, texture and
structure
Water retention
Hydraulic conductivity
Depth to impermeable
layer (and GWT)
Surface storage
Downslope and lateral
water movement –
need additional math
Soil Texture
Sat Hyd
Conductivity
(ft./day)
Sand
18.9
Loamy sand
4.72
Sandy loam
1.73 (52 cm)
Loam
1.02 (31 cm)
Silt loam
0.54
Sandy clay
loam
0.24
Clay loam
0.16
Silty clay loam
0.16
Sandy clay
0.09 (2.7 cm)
Silty clay
0.08
Clay
0.05
Average Saturated Hydraulic Conductivity Values
Source: Rawls et al. (1993)[2]
Site Variability --- Precision Drainage and Irrigation
Site Variability --- Site Investigation and Modelling
Photo courtesy
of Precision
Land Solutions
30
Texture vs. Hydraulic Conductivity
Soil Texture
Sand
18.9
Loamy sand
4.7
Sandy loam
1.7
Loam
1.0 (1.3 cm/hr)
Silt loam
0.54
Sandy clay loam
0.24
Clay loam
0.16 (0.2 cm/hr)
Silty clay loam
0.16
Sandy clay
0.09
Silty clay
0.08
Clay
0.05
Hydraulic Conductivity
Guelph Permeameter
Example - Fine sandy loam
7 sample sites on 100 + acres
Guelph Permeameter at 30 and 75 cm
Varies 2.3 cm/hour to 4.2 cm/hour at 75 cm
Compaction/ infiltration issues, lower
readings at shallower depth ?
32
Soil Texture and Structure vs. Tile Depth
Example --- Fine Soils ---- Drainage Guide for Ontario
Preferential
flow
in cracks
S-1 Fine textured surface and blocky or massive B and C.
Hydraulic conductivity low. Relies on soil cracking, deep
tillage, mole drainage IF tiled. Surface drainage first solution.
S-2 Somewhat coarser than S-1. Finer texture B and C
horizons. Extensively drained in Ontario. Drains should not
be deep and should be placed in B horizon for best results.
Salinity Mapping
Saline areas match to soils
well and also to yield maps for
this quarter
Question tile poorest yielding,
most saline soils first ?
Question install tile shallow to
limit salt movement
downstream ?
Question any upward flow
(artesian) conditions ?
Depth to Impervious Soils
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EM31 utility
deep texture
mapping
E.g. depth to
impervious clay or
depth averaged clay
Hydrogeologic
anomalies (to 12
feet) (silt, sand, etc.)
EM34 available
Landscape Affects Surface Runoff and Drainage Class and
Drainage Coefficient
Increase drainage coefficient IF surface
drainage admitted directly into the pipe drain
Critical to Understand Geology –
Use Available Information
(e.g. well logs, regional geology maps and studies )
Downslope water movement
Artesian conditions require geology/engineering
Drainage coefficient ? – Downstream impacts ?
Source of salts ?
WELL LOG
From To
Log
(ft.) (ft.)
0 6.0 BROWN TILL
6.0 8.0 SAND
8.0 10.0 BROWN SAND
10.0 14.0 GRAVEL
14.0 22.0 BROWN TILL
22.0 40.0 GREY TILL
40.0 55.0 SHALE GRAVEL
55.0 70.0 GREY TILL
70.0 160.0 SHALE AND CLAY
No construction data for this well.
37
Sodic Soils Hazard Assessment
NDSU Approach is Systematic
Case Study --- Homewood
Soil surveys
1:20,000 map
PME, EBG, RGB, DHO, JOD, GYV
Veris
comparison to soils surveys
depth to sand layer or no sand (auger holes)
Variable spacing
30 – 60 feet
landscape (top slope vs downslope)
texture/hydraulic conductivity VARIES, use 1:20,000
BMPs
Controlled drainage/subirrigation (BMP)
Monitoring data
Adcon (soil moisture, GWT)
Soils Investigations…
40
2011 -- Early Adopter Field Scale Controlled Drainage
Seven Control Structures ---- 300 acres
Producer influenced by test
plots at Hespler and CMCDC
Contractor interested in value
added
Producer looking at “long term”
Contractor needed technical
assistance
Monitor performance critical
(e.g. does it work)
Professional input provided
Yield North 150 Acres – 2013
Explain Using Soils Zones and Subirrigation ?
Value of models ?
Sub Irrigated Corn Manitoba – 25 acre trial 2013
300 acres Controlled Drainage
43
Design Tools - Internet
South Dakota State University
http://climate.sdstate.edu/water/DrainSpacingCal.html
Computer Simulation Models
DRAINMOD – North Carolina
State University
Climate
Soils
min/max temp
precipitation
ET crop
freeze/thaw
soil water characteristics
Ksat
drainage volume
infiltration
upflux
soil water content
Seepage
Drainage System Parameters
Crop Parameters
http://www.bae.ncsu.edu/soil_water/documents/Dr
ainmod.Model.Use.Calibration.And.Validation.pdf
http://www.bae.ncsu.edu/soil_water/methods_data/Sustai
nable_High_Yields_on_Poorly_Drained_SoilsPres_Color.pdf
Sands et al., 2013
University of Minnesota
Used DRAINMOD
Looked at 6 soils, 3 locations
100 years data
Averaged impacts and yield (relative)
Very similar to MORDEN – 20 inches precip
Increase tile drainage coefficient => decrease surface
runoff
http://www1.extension.umn.edu/agriculture/water/reports/docs/final_report_
_developing_drainage_guidelines_for_rrb_sands.pdf
46
DRAINMOD – Non Tiled – 2010 Weather Data – Clay Loam
0
2010-05-20
2010-07-09
2010-08-28
2010-10-17
50
20
WT Depth (cm)
40
40
60
80
100
120
140
160
Water Table Depth
Rainfall
Drainage (Total)
Surface Runoff (Total)
30
20
10
180
200
0
Rainfall/Drainage/Runoff (cm)
2010-03-31
DRAINMOD - Tiled – 2010 Weather Data – Clay Loam
0
20
40
WT Depth (cm)
60
80
100
120
140
160
2010-05-20
2010-07-09
2010-08-28
Water Table Depth
Rainfall
2010-10-17
50
Drainage (Total)
Surface Runoff (Total)
40
30
20
10
180
200
0
Rainfall/Drainage/Runoff (cm)
2010-03-31
DRAINMOD Results – Red River Valley
Sands, 2011; Sands et al. 2013
http://www.redriverbasincommission.org/Conference/Proceedings/28th_Proceedings/Sands.pdf
Increase DC = Closer Tiles
Where Can You Add Value