This research and education project evaluated the crop yield, water quality and water balance for four different fields, undrained (UD), subsurface drained with free outlet (FD), subsurface drainage with controlled drainage structure (CD), and CD plus subirrigation (SI). From 2012 to 2014, the crop yields showed some promising improvement with the dual CD and SI system setup despite the extreme wet and drought conditions during the experimental period. Water quality monitoring showed that the CD retained the drainage outflow and improved the water quality comparing to the FD when most rainfall occurred in spring and early summer. However, when rainfall occurred in summer and early fall of 2014, the effect of CD on water quantity and quality control was not significant better than that in the FD field. The economic analysis showed that with only $45 input per acre per year, the dual CD and SI would be paid back in few years because at least 10% yield increase between CD and SI for all three years, and 25% yield increase for SI in two of the three years have obtained. The water balance for the four fields also showed that with only 1.79 inches of water supply for 13 days in July and August, the SI field had minimal deficiency between inflow and outflow, and created an optimal soil water regime for the crop. Enormous educational opportunities were also provided for university students, staff, and faculties, land owners, governmental personals by the research team, collaborators, and most importantly, the participating landowners.
In the last decade, following a wet weather pattern in the Red River Valley of the North (RRV) of eastern North Dakota and northwestern Minnesota, subsurface drainage has become the most effective way to combat excess soil water in farm fields. Subsurface drainage (often called tile drainage) uses perforated conduits to remove excess water from the soil in a field. This results in improved field trafficability in the spring and fall, increased crop yields, and reduced prevented planting acres. These benefits have accelerated subsurface drainage installation in the last 17 years in the RRV.
It is well known that subsurface drainage water can contain high nitrate-nitrogen (NO3-N) during certain periods of the growing season. The elevated NO3-N in the tile discharge water can contaminate surface water systems. Leaching of NO3-N also implies a loss of N fertilizer from farm fields. Many subsurface drainage systems in the RRV either have a gravity outlet or use a lift station. These are uncontrolled or free drainage (FD) systems. Using control structures or weirs to hold the subsurface water in the drained field can minimize the amount of water removed from the field in late spring and reduce the loss of NO3-N. This practice is called controlled drainage (CD). Additionally, with a reliable source, water can be added to the field through subirrigation (SI) during high crop water demand periods such as in July and August. The dual CD-SI system is expected to allow for a higher crop production and increase the farmer’s net income if proper water management practices are applied.
When using CD, the amount of water leaving the field is reduced which results in less NO3-N leaving the field. In the RRV the major surface-water quality problems are high phosphorus (PO4-P) and sedimentation. When water in the drainage ditch is used as the SI water source, PO4-P and solid particles are filtered out to stay either in the soil, or outside the field. With proper CD and SI practices, it is possible to achieve an optimal soil water status in the farmer’s field and obtain an economic benefit.
Under normal weather conditions, FD, CD, and SI could all be practiced on the same field at different times of the season while the crops in undrained fields (UD) may suffer from waterlogging stress. However, every growing season is different and there may be times when crops may not need SI water if the soil has sufficient moisture. On the other hand when extremely dry conditions occur the UD field may provide a better subsurface moisture condition for the crop in spring and the SI system could provide additional water to crops during the growing season to combat drought stress. The dual CD and SI system has been shown to increase crop yields in both dry and wet years and can potentially reduce the impact to surface water quality.
For this project, our objectives were to (1) optimize water management through a CD and SI system on a farmer’s production field; (2) compare yield differences between UD, FD, CD, and CD+SI fields; (3) monitor water quality (e.g. NO3-N, PO4-P, turbidity, salinity, etc.) and quantity for fields with different water management practices; and (4) estimate the total annual water balance in the UD, FD, CD, and CD+SI fields.
The experiments were conducted in four fields, located within Morken Township, Clay County, MN. All fields were close to each other and adjacent to a legal County Drainage Ditch, just before it discharges into the Buffalo River. The Buffalo River merges with the Red River about 10 miles north and west of the field. There were four fields each with a different water management practice. As shown in figure 1, the practices were; undrained (UD, 40 ac), free tile drainage (FD, 60 ac), controlled drainage (CD, 43 ac), and controlled drainage plus subirrigation (SI, 51 ac).
The dual CD and SI system uses 3-inch diameter tile at a drain spacing of 40 feet installed at a depth of 3 to 4 ft. The gradient is 0.1%, where the drainage and irrigation both flow from the east to the west side of the field (Figure 1). The total area of the CD and SI field is 135 ac, which was further divided into three sections, with 41, 43, and 51 ac in the north, middle, and south part of the field, respectively. Each section has individual mains for drainage and irrigation. The drainage mains are located on the west side of the field and the irrigation mains are on the east side of the field. In 2012, the middle section was used as CD and the south section for CD+SI. In 2013 and 2014, the middle section was CD+SI and the south section was used for CD only. The north section was not used for the experiment because it was adjacent to the drainage ditch. The UD field was 40 ac, located north of the CD and SI fields, while the FD field has 60 ac located northeast of the CD and SI fields. All fields have similar soil properties, with Bearden silt loam soil mainly in the CD and SI field, and Colvin silty clay loam in the UD and FD fields. The Bearden silt loam is classified as somewhat poorly drained, and more than 80 inches to the restrictive layer. The Colvin silty clay loam is classified as poorly drained, and more than 80 inches to the restrictive layer. The biggest difference between the two soils was the landscape shape and hydraulic conductivity, 0.14 – 1.42 in/hr for Bearden silt loam, and 0 – 0.14 in/hr for Colvin silty clay loam.
Since all of these fields are at least 40 ac in size, it was not feasible to install an isolation barrier around the field to control lateral water movement. Therefore the experimental design was a split block design with 3 replicates in each block. In each field, three pairs of observation wells each 6 feet in depth were installed and randomly located in the upper, middle and bottom portions of the field. For each pair, one well is located close to the tile and the other is centered between two tile lines. The water level in each of the 24 observation wells was recorded every 30 minutes. The observation wells were screened from 1 foot below the soil surface to the bottom. During planting and harvesting, the wells were buried 8 inches below the ground to clear the field entirely for large farm machinery to operate. The observation wells were left in the field year round. With a detailed field survey, the water levels in the field were compared with the water levels at the drainage outlet to guide the CD practice in the spring and fall.
The measured water balance components, for the four fields, included rain, snow, surface runoff, subsurface drainage, subirrigation, evapotranspiration, and soil water storage change. Rainfall was measured using a tipping bucket rain gage. Snow depth was measured using a sonic distance sensor, and snow equivalent water content was measured using a modified rain gage with an antifreeze reservoir on top. Due to multiple surface runoff outlets in each field, it was not possible to measure field runoff at one location. Instead, V-notch weirs (90o angle) were installed in multiple outlets, and grab water samples were collected. In each V-notch weir, a transducer was installed in a perforated pipe about 1 foot in front of the weir to measure the water level change. Flow rate was calculated from the measured water level above the bottom of the V with the discharge equation for a 90° V-notch weir. Subsurface drainage from the CD and SI fields was measured using a V-notch weir cut into the top board (60o angle) and water level sensors inside the control boxes. The reference level was measured each time during field visits. The flow rate and volume were calculated using the discharge equation for a 60° V-notch weir. The drainage amount from the FD field was measured using a portable area-velocity flow meter (Stingray 2.0, Greyline Instruments, Massena, NY). The sensor was installed inside the outlet that was along the surface drainage ditch. Subirrigation volume and flow rate was measured by the two flow meters, one for the entire field and the other for the SI field only. A notebook was placed by the flow meter to ensure the team and the landowner recorded the flow rate as frequently as possible. The pump was controlled by a variable frequency drive (VFD) so a sensor was installed in the power panel to continuously record the current draw, and based on the pump characteristic curve; the flow rate and volume pumped were estimated.
The evapotranspiration rate for the SI site was measured by three methods, eddy covariance (Eddy), soil moisture deficit (SMD), and photosynthetically active radiation (PAR). At the CD site, ET was measured by SMD method and at the UD and FD sites; ET was measured by the PAR method. All weather stations and soil moisture sensors were setup to run in the winter and were remotely accessed through either cellular or radio devices. ET was determined by the three methods with eddy covariance serving as the standard method. With a good understanding of the ET at the SI site, the ET at the other fields could be estimated. Instruments used in the research are listed in Table 1.
Water quality monitoring systems were installed in the ditch upstream and downstream from the SI field to continuously measure water depth, turbidity, pH, electrical conductivity, and temperature. In the summer 2013, large and frequent rain events caused a sudden water rise in the ditch and river that damaged all the instruments. Because it was not possible to set up a suspension system to hold the sensors, the research team decided to measure the same parameters manually on a weekly schedule, instead of continuously. Water samples were collected weekly at the up and downstream sites and at the three control drainage flow structures located near the outlet for the CD/SI field. Chemical analysis of the water samples from the up and downstream sites were used as an indicator of water quality improvement due to SI or field filtration. Surface runoff and free drainage water samples were also collected on a weekly schedule if possible. The analyses for pH, EC, K, PO4-P, and NO3-N in these samples were reported.
Each fall, crop yields were determined by hand harvesting for the CD, SI, FD, and UD fields. The landowner via a weigh cart also provided bulk crop yield.
Since CD and SI are relatively new in this region, many farmers would like to apply SI to their land if water sources are available. However, the methods, techniques, and considerations for SI practices in the RRV are not readily available. We have addressed the concerns through conference presentations and publications. Extension team members conducted outreach educational activities, such as field days, and workshops, all three years of the project. Publications were developed and all team members made presentations at state, regional, and national research and extension meetings.
- Table 1. Number of instrument applied in undrained (UD), free drained (FD), controlled drained (CD), and controlled drained and subirrigated (SI) fields in 2012 – 2014.
- Figure 1. Experimental layout in 2012, while in 2013 and 2014, the control drained and control drained/subirrigated fields were switched.
Drainage water management:
The proposed work was to optimize a soil water regime for better crop production through a water balance approach. Before the model was developed, a simple approach was used to guide day-to-day water management. A detailed topographic survey was conducted in the spring of 2014 with help from a ND NRCS engineer, and special attention was paid to key bench points, such as the control structures and observation wells. After elevations were measured, we found that the water levels for the entire field were within 0.3 feet of difference from the highest point in the southeast part of the field to the lowest location at the control drainage structures (Figure 2). By targeting a minimal water table 2.5 ft. below the surface for the majority of the field in each zone during CD and SI, the top boards inside the control structures were set at 2.5 and 4.0 ft. for the CD and SI fields, respectively. With continuous water loss through evapotranspiration and possible deep seepage, the water level in the field was normally below 2.5 ft. When heavy rainfall occurred, the excess water in the top 2.5 ft. would flow over the board inside the controlled drainage structures. This simple tool was used by the landowner as a guide for scheduling CD and SI practices. This water table setup also provided a starting point for inverse modeling of optimal water management through the checkbook water balance model. The actual model based on soil water deficit should be nearly equal to the water table setup values.
Crop yields for each field were hand-harvested each year from 2 rows, 20 ft. long at two locations over the drain and in the middle between two drains. In general, the six sampling points in each field were located 20 ft. away from the observation wells, which were south in UD and FD fields, and to the west in the CD and SI fields. Bulk yield by weigh cart was also done for the CD and SI fields, but not for the UD and FD fields. The crop yields are listed in Table 3.
Because the four fields belong to two landowners, there are differences in field management, fertilizer rate, variety, and more importantly, crop rotation. It was inappropriate to directly compare their yields with each other; instead, county average yields were used for comparison purposes. The county average yields are also listed in Table 3.
In 2012, all four fields were planted with corn. The UD and FD fields had higher crop yields compared to the CD and SI fields. Due to the drought conditions and the inability to supply water to the SI field due to the perforated delivery pipe, the CD and SI systems had the least favorable soil water conditions for crop production. In addition, the corn variety used in the UD and FD was short season (84 day) , while the CD and SI field used a mid to late season corn variety (93 day). A poor germination rate was visually observed in the CD and SI fields due to either lack of soil water or the corn variety. In addition, the previous crop for the UD and FD fields in 2011 was soybean, but for the CD and SI fields, the previous crop was sugarbeet. A 60-bu/ac yield difference could be observed for corn due to the difference in previous crop whether it was soybean or sugarbeet. When considering the rotation effect, the corn yield in the CD and SI fields was acceptable because only controlled drainage was practiced, while SI was not available when needed.
In 2013 and 2014, due to heavy rainfall events in June, the UD field was under waterlogged conditions for a long period of time. The lower crop yield in the UD field was probably due mainly to the wet conditions. The CD and SI fields benefited from the controlled drainage, because the additional water was held in the field instead of flowing away. According to the annual report in 2013, more than 75% of drainage water was kept in the field due to control drainage practice by comparing the drainage outflow from the FD and CD. Figures 3, 4, 5, and 6 show the daily average soil water measurements throughout the growing season in the four fields, using only the top 30 cm layers because all fields have soil water measurements at 5, 15, and 30 cm depth, but only the CD and SI fields have soil water measurements up to 90 cm depth. Field capacity of 33% and 30.2%, and permanent wilting point of 20.1% and 15.7% for Colvin silty clay loam in the UD and FD field and Bearden silt loam in the CD and SI field, respectively, are also indicated in the figure.
Water table monitoring in the four fields also provides an indication of the water status in the field, whether during drought or excess water conditions. The daily average water table elevation for the two middle observation wells are plotted in Figure 7 and 8 with daily rainfall plotted at the top of the figures for 2013 and 2014. Because of the dry weather in 2012, the water table was below 6 ft. in the FD, CD, and SI fields, while in the UD field, the water table was 4-5 ft. below the surface in springtime.
Figures 7 and 8 clearly showed that the crop in the UD field was waterlogged in 2013 and 2014, but optimal water status was seen in the CD and SI fields during the same period. There were 26, and 37 days in 2013 and 2014, respectively, that the water table was within 2 ft. to the surface for the UD field. The waterlogging conditions definitely would affect the crop yields.
The improvement of water quality in the surface water was achieved through two pathways, one is the reduction of drainage water and its nutrients into the surface water through controlled drainage, and the other is the reuse of the surface and subsurface drainage ditch water through the subirrigation process. Figure 9 compared the amount of water and its nutrient and salt loads from the CD and FD fields in 2013 in order to show the amount of nutrients retained in the field.
From the figure 9, it was seen that a total of 10.75 lbs/ac of NO3-N, 0.02 lbs/ac of PO4-P, and 263.48 lbs/ac of total amount of salts were retained in the field due to 23 days of control drainage.
Figure 10 shows the daily flow volume and nutrient loads that were applied to the field in 2014 since it has detailed water application measurement records.
The results in 2014 showed that a total of -2.08 lbs/ac of NO3-N, 0.02 lbs/ac of PO4-P, and 244.48 lbs/ac of total amount of salts were retained in the field. The results in 2014 were very different from the results in 2013, where the CD field should have less drainage water and less nutrient from the field compared to the FD field. After examining the data, we found that a large amount of drainage outflow occurred after September 4 when CD ended and FD started in the CD field. The large amount of flow and the associated nutrient and salts loads were probably accumulated amounts that were held in the soil over time during the CD period. This resulted in longer drainage duration for the entire season, which were 75 and 98 days of drainage in the FD and CD fields, respectively. Because the drainage mains for CD and SI plots were all perforated and next to each other at the west side of the field, it is possible that the CD main intercepted additional water from the SI mains (center and north of the field) when it was near the outlet. When that happened, the drainage flow from the CD field was not solely water in the CD field, but a water mixture from the CD and SI fields. In addition, the CD main was the longest main among all three fields, and right below a surface drainage ditch. When surface runoff formed, it was possible that the CD main received seepage from the surface. However, it was difficult to conclude what the sources of water were from the CD field, or they might be a combination of several sources mentioned above.
The second benefit was due to the SI practices that applied surface drainage ditch water to the field. Figure 11 shows that with only 1.79 inches of subirrigation for 13 days; 0.31, 0.44, 163, and 1.46 lb/ac of NO3-N, PO4-P, K, and salt were supplied to the field and used by the crops in the SI field.
The nutrient amounts are much lower compared to what was drained during the spring; however, the time of SI application was in the critical stage when the crop needed water and nutrients the most. That is why an 11% yield increase was observed between the CD and SI fields. In addition, higher K concentration was found in the surface water, which resulted in a total of 1.46 lb/ac of K applied to the field due to SI. This benefit to crop should be further investigated.
Upstream and downstream of the CD and SI field, or before and after SI was used, or drainage was leached out, the chemical parameters were also monitored and compared in Figure 12.
The results showed that the drainage and subirrigation processes did not significantly change the water chemistry according to the major nutrient parameters, including NO3-N, NH4-N, and PO4-P. This was probably because the flow rate was small from the drainage outlet or into the field through subirrigation practices field, comparing to the flow rate in the ditch, and thus there is a significant dilution factor. However, the K concentration, and EC and pH values were significantly different between the upstream and downstream sites, probably due to the concentrated drainage outflow that came from the 135 ac field located right before the downstream sampling location. In summary for all three years, we observed 0.35 mg/L increase in NO3-N, 0.02 mg/L of NH4-N decrease, 0 mg/L in PO4-P, 0.03 mmho/cm of EC increase, 0.14 decrease in pH, and 0.18 mg/L increase in K in the downstream water when compared to the upstream water.
The water balance consists of the difference between the inflow from precipitation and irrigation, and outflow from evapotranspiration, drainage, and surface runoff. The evapotranspiration comparison for three methods, Eddy covariance, PAR, and SMD, showed promising results using the 2012 data (Kolars et al., 2013). However, when the 2013 and 2014 data are included, the relationship between the PAR and Eddy was not correlated strongly. Instead of using soil water data only for the correction, we are looking at using the change in water over time to correlate the ET rates from PAR method to ET rate from Eddy covariance, in order to extend the results to all three fields. The ET by soil water deficit method was simple in theory, but the day-to-day variations overcame the actual ET rates. An inverse modeling approach is proposed to solve the residual of ET by the SMD method. At this stage, the actual ET is only available in the SI field using the Eddy covariance method (Figure 13).
Based on the measured ET rates using the Eddy method, crop coefficients were developed for corn and soybean using the three years’ data. The crop coefficient (Kc) is a ratio between crop ET and reference ET. Once Kc for a specific crop was developed in that region, it allows people to estimate crop ET based on reference ET that are readily available. These Kc values in Clay County MN were compared to the Kc values that were measured in a subsurface drained field in southeastern North Dakota (Rijal et al., 2012). The monthly Kc results at the two locations were very similar for corn, but different for soybean. The results are listed in Table 4.
From table 4, we found that the Kc values for corn was similar for the two sites, while only a minimal amount of irrigation was applied to the MN site in 2012 and 2013 when the Kc for corn was developed. However, the Kc for soybean was very different between the two locations, possibly due to the effect of subirrigation at the MN site that was applied in 2014.
Another challenge during the experiment was the surface runoff measurement. Each field had multiple outlets that collected surface runoff, and some outlets consisted of composite flows from multiple fields. Without a detailed delineation of each drainage area, the surface runoff measurement would not be representative of the field, especially since each had a different water management practice. The UD field did not have a natural surface runoff outlet, while all surface runoff water flowed parallel into the ditch west of the field. This ditch collected flows from the south and east of the field and flows to the northwest corner of the field for a mile long distance. Unless it was very high flow, most of the surface runoff water in this ditch stayed there until it seeped downward or evaporated upward. Over the three-year experimental period, we haven’t measured any surface water from the UD field flowing into the main drainage ditch. Surface runoff water in this field had to be estimated from models with known soil water conditions in the field. The surface runoff in the FD field was setup to be measured with a V-notch weir, but was removed by the landowner because when surface runoff happened, any constraints to the flow were not acceptable. In addition, the surface runoff ditch collected water from adjacent fields as well. Three V-notch weirs were setup in the CD and SI fields to measure the surface runoff. Water samples were collected weekly when they were available. A new USDA NIFA grant was started in March 2015 and for the next five years will be using the current experimental setup. This project will solve the surface runoff problems that have been encountered thus far. More resources, such as ultrasonic flow meters, will be used to measure the surface runoff without creating backwater on the field thus making them acceptable to landowners.
Therefore, a simple water balance for the four fields without considering the variations on ET and SR measurements are shown in Figures 14.
The snowfall, snow equivalent water content, and soil water and temperature regime measurements were the preliminary data used to apply for a NASA grant on snowmelt runoff modeling in the Red River Basin. This new project would be conducted in the next four years using some of the existing instrument setup, but with more quantification of water infiltration into frozen soils.
- Figure 4. Daily average soil moisture measurements for the top 1 ft. (30 cm) in the free drained (FD) field in the growing seasons of 2012 – 2014.
- Figure 12. Water quality parameters for samples collected from the drainage ditch upstream (U) and downstream (D) of the controlled drainage and subirrigation fields in 2012-2014.
- Figure 13. Evapotranspiration rate by eddy covariance (ETc_Eddy), and reference evapotranspiration rate by Penman (ETr_Penman) and Jensen-Haise (ETr_Jensen-Haise) methods in the subirrigation field in 2012 – 2014.
- Table 3. Crop yields for the undrained (UD), free drained (FD), controlled drained (CD), and controlled drained and subirrigated (SI) fields compared to Clay County averages (Avg.) in 2012-2014.
- Figure 10. Drainage outflow, and nitrate-nitrogen (NO3-N), orthophosphate (PO4-P), and salt loads in the free drained (FD) and control drained (CD) fields in 2014.
- Figure 9. Drainage outflow, and nitrate-nitrogen (NO3-N), orthophosphate-phosphorus (PO4-P), and salt loads in the free drained (FD) and control drained (CD) fields in 2013.
- Figure 11. Subirrigation (SI) amount and the corresponding salt load (upper figure) and nutrients loads (bottom figure) added to the SI field in 2014.
- Figures 14. Water balance for undrained (UD), free drained (FD), control drained (CD), and control drained plus subirrigated (SI) fields between inflow for rainfall (Rain) and subirrigation (SI), and outflow for subsurface drainage (SD) and evapotranspiration (ET) in 2014.
- Figure 6. Daily average soil moisture measurements for the top 1 ft. (30 cm) in the control drained and subirrigated (SI) field in the growing seasons of 2012 – 2014.
- Figure 8. Daily average water table changes in undrained (UD), free drainage (FD), controlled drainage (CD), and controlled drainage and subirrigation (SI) fields in 2014.
- Table 2. Controlled drainage (CD) and subirrigation (SI) schedules in all three years.
- Figure 2. This is a topographic map of the field showing the elevation differences in the controlled drainage and subirrigated fields.
- Figure 3. Daily average soil moisture measurements for the top 1 ft. (30 cm) in the undrained (UD) field in the growing seasons of 2012 – 2014.
- Figure 5. Daily average soil moisture measurements for the top 1 ft. (30 cm) in the control drained (CD) field in the growing seasons of 2012 – 2014.
- Figure 7. Daily average water table changes in undrained (UD), free drainage (FD), controlled drainage (CD), and controlled drainage and subirrigation (SI) fields in 2013.
- Table 4. Crop coefficients for corn (Kc_Corn) and soybean (Kc_Soybean) using the Penman reference evapotranspiration method for subirrigated field in Clay County, MN (MN). Rijal’s Kc values from southeastern ND (ND) are also included.
Though there were some challenges on the water balance component measurements, the impacts of the results in the RRV are obvious. In a short term, we have enhanced the knowledge of CD and SI operations for the landowners and others involved in the project. We have developed an easy to follow management protocols for the CD and SI practices using detailed topographic survey results. The crop yields in the SI are in general 10% higher than that in the CD field. The water quality improvement through the CD was significantly larger in 2013, but marginal in 2014 because of the wet weather conditions.
The intermediate outcomes of the project were to develop guidelines for design, management and installation of controlled drainage and subirrigation system. We have published a conference paper to address this issue, conducted preliminary field-testing on SI system evaluations in summer 2014, and a publication is in progress. Adoption of the CD and SI technology by other growers in MN is sometimes complicated by the permitting process. At least two more fields in MN were planned for CD and SI application as affected by this project. CD and SI were recognized as potential BMP’s for water management in the RRV, and one of the watersheds in MN recently required landowners to install CD structures for any new drainage system.
The economic analyses for tile drainage and control drainage have been conducted previously by many researchers. In this section, we would like to focus on the economic analysis of the SI system. Table 5 showed the economic analysis of the SI system.
With corn price of $7 and $4.37 in 2012 and 2013, and soybean price of $10.2 in 2014, the benefits are -$51.8, $163.9, and $194.8 per acre comparing the crops in the SI to the average crop yield in Clay County, MN. If considering the difference caused by crop rotation in 2012 and adding 60 bu/ac yield, the benefit would have been $368.2. If the entire 135-ac field had been subirrigated, the benefits would have been $22,123 and $26,301 in 2013 and 2014. Using the same SI system, an adjacent 150 ac of land was also irrigated. Therefore, the benefit due to cost sharing should be higher than what was listed in Table 5.
The landowner who was cooperated on this project has extended the system from one field to four fields. He also managed to subirrigate his crops in the most economical way using the 6 inches per acre per year water permit. We have also attended a legal hearing and shared our research proposal to people who shared the ditch and its water. Most people were persuaded that the project would benefit the landowners instead of causing trouble, because the SI practice cleaned up their polluted ditch waters. More farmers would like to adopt, but challenges exist on how to do it. Some watersheds in MN have mandatory regulations that required all new tile drainage systems to have drainage control.
For over 15 years, North Dakota State University Extension, South Dakota State University Extension and the University of Minnesota Extension Services have conducted several 2-day tile drainage design workshops each winter. Since 2011, over 750 farmers, contractors, government agency personnel and others have been trained in basic design concepts. The cooperator on this project has given presentations on his controlled drainage and subirrigation system at the workshops held in the RRV. As a result, he has been contacted directly by farmers across the region to discuss his project. Drainage water management concepts and applications comprise one of the five design sessions covered in the workshop. Subirrigation has been included as part of the curriculum for the last 3 years. Much of the information for this particular design session came from this project. Many farmers and contractors in the RRV have installed control structures at their own expense. Many farmers have expressed interest in using subirrigation but commonly run into the problem of finding an adequate water supply. However, there are at least 5 subirrigation systems that have been developed and installed in the RRV during the last 3 years.
In addition to the workshops, since 2011 presentations on controlled drainage with subirrigation concepts have been given at over 200 meetings held in the RRV and throughout North Dakota and northwest Minnesota. Many presentations were organized by county Extension agricultural agents to coincide with annual crop improvement meetings; some were given at meetings with commodity groups, some for government agency personnel and some as part of other Extension activities. In addition, this project has been an education stop on 8 tours and has been used for training over 100 NRCS personnel in basic drainage water management concepts.
Educational & Outreach Activities
- Jia, X., D. Steele, T. Scherer, K. Kolars, and K. Horntvedt. 2014. Measuring subirrigation efficiency and uniformity on two subirrigation fields in the Red River Valley. 2014 Eastern South Dakota Water Conference. October 29, 2014. Brookings, SD.
- Jia, X. 2014. Subirrigation design. 2014 Extension Subsurface Drainage Design & Water Management Workshop. Wahpeton, ND. February 11-12, 2014.
- Jia, X. 2014. Tiling water management. North Dakota’s 11th Annual Certified Crop Advisers Meeting. Fargo, ND. January 21, 2014.
- Jia, X. 2014. Tile drainage converted to controlled drainage and subirrigation. Red River Basin Commission 31st Annual Conference. Fargo, ND. January 13, 2014.
- Jia, X. 2013. Subirrigation research – putting water into drain tile. ND Irrigation Workshop, Bismarck, ND. December 12, 2013. Presentation by Jia.
- Jia, X. 2013. Subirrigation research in North Dakota. MN Drainage Water Management Conference, Alexandria, MN. December 5, 2013.Presentation by Jia.
- Jia, X. 2013. Subirrigation research in North Dakota. IA-MN-SD Drainage Forum, Sioux Falls, SD. November 14, 2013. Presentation by Jia.
- Jia, X., Ransom, J., and Roy, D. 2013. Raising corn in Northern Climates with plastic mulch. Fargo, ND. September 10, 2013. Presentation by Jia.
- Jia, X. 2013. Impact of water resources and quality on crop production and environment. Xinjiang Agricultural University. Urumqi, Xinjiang, China. July 29, 2013. Presentation by Jia.
- Jia, X. 2013. Impact of water resources and quality on natural resources and environment. Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences. Urumqi, Xinjiang, China. July 30, 2013. Presentation by Jia.
- Kolars, K., X. Jia, D. Steele, T. Scherer, and T. DeSutter. 2013. Using eddy covariance, soil water deficit, and photosynthetically active radiation methods for corn evapotranspiration measurements in the Red River Valley. 2013 ASABE Annual International Meeting. Kansas City, Missouri. July 21-24, 2013. Presentation by Kolars.
- Horntvedt, K., X. Jia, T. Scherer, D. Steele, and T. DeSutter. 2013. Methods, techniques, and considerations for subirrigation practices in the Red River Valley of the North. 2013 ASABE Annual International Meeting. Kansas City, Missouri. July 21-24, 2013. Presentation by Horntvedt.
- Jia, X., and T. Scherer. 2013. Reducing cost of water quality monitoring in tile drainage outflow using electrical conductivity as a surrogate. Seventh International Conference on Irrigation and Drainage. April 15-19, 2013. Phoenix, AZ. Presentation by Jia.
- Jia, X. 2013. North Dakota State Drainage Research Report. NCERA 217 Annual Meeting, Sioux Falls, SD. April 9-11, 2013. Presentation by Jia.
- Jia, X., T. Scherer, D. Steele, and T. DeSutter. 2013. Effect of optimal water management for sustainable and profitable crop production and improvement of water quality in Red River Valley – subirrigation system. 2013 Extension Subsurface Drainage Design and Water Management Workshop, February 12-13, 2013. Moorhead, MN. Presentation by Jia.
- Jia, X., T. F. Scherer, D. Lin, X. Zhang, and I. Rijal. 2014. Comparison of reference evapotranspiration calculations for southeastern North Dakota. Irrigation & Drainage Systems Engineering 2:112. doi:10.4172/2168-9768.1000112.
- Rahman, M. M., Z. Lin, X. Jia, D. D. Steele, and T. M. DeSutter. 2014. Impact of subsurface drainage on stream flows in the Red River of the North basin. Journal of Hydrology 511: 474-483.
- Jia, X., F. Scherer, D. Lin, X. Zhang, and I. Rijal. 2014. Comparison of reference evapotranspiration calculations for southeastern North Dakota. Irrigation & Drainage Systems Engineering. Accepted.
- He, Y., T. M. DeSutter, D. Hopkins, L. Prunty, X. Jia, and D. Wysocki. 2013. Relating the value of EC1:5 to ECe of the saturated paste extract. Canadian Journal of Soil Science. 93: 585-594.
- Jia, X., and T. Scherer. 2013. Reducing cost of water quality monitoring in tile drainage outflow using electrical conductivity as a surrogate In Using 21st Century Technology to Better Manage Irrigation Water Supplies, Seventh International Conference on Irrigation and Drainage Proceedings. Edited by Wallin, B. T., and S. S. Anderson. U.S. Committee on Irrigation and Drainage, Denver, CO. Pp. 213-225.
- Rijal, S., X. Zhang, and Jia. 2013. Estimating surface soil moisture in the Red River Valley of the North Basin using Landsat 5 TM data. Soil Science Society of American Journal 77:1133-1143.
- Kolars, K., Jia, D. Steele, T. Scherer, and T. DeSutter. 2013. Using eddy covariance, soil water deficit, and photosynthetically active radiation methods for corn evapotranspiration measurements in the Red River Valley. 2013 ASABE Annual International Meeting. July 21-24, 2013, Kansas City, Missouri. Paper No. 131591426.
- Horntvedt, K., Jia, T. Scherer, D. Steele, and T. DeSutter. 2013. Methods, techniques, and considerations for subirrigation practices in the Red River Valley of the North. 2013 ASABE Annual International Meeting. July 21-24, 2013, Kansas City, Missouri. Paper No. 131618357.
- The SARE site was included as a field tour for two, daylong drainage water management (DWM) training sessions for Natural Resource Conservation Service (NRCS) personnel. Over 50 NRCS employees visited the site and heard presentations by the project leader, Xinhua Jia, as well as the landowner, Mr. Zimmerman.
- The SARE site installation and yield results have been and will continue to be used in Drainage Design Workshop presentations by Extension engineers as an example of one method of subirrigation.
- The landowner, Mr. Zimmerman, was a guest presenter at Drainage Design Workshop held in Grand Forks. He provided the farmer/tile installer perspective to the workshop attendees.
- September 13, 2013. Host a field tour to visit the USDA SARE research site with 33 attendees.
- August 7, 2013. Served as a tour site for NDSU extension to visit the USDA SARE research site with 12 attendees.
- A subsurface drainage website was created to display results from drainage outreach and research (http://www.ag.ndsu.edu/tiledrainage).
- Extension publications available at http://www.ag.ndsu.edu/publications/crops/irrigation-and-drainage; AE1690 Frequently Asked Questions about Subsurface (Tile) Drainage and AE1747 Tile Drainage Pump Stations for Farm Fields.
Project blog: http://aben-saregrant-ndsu.blogspot.com/
This blog was created with the intent to keep the public updated and informed about the research activities. Field pictures of field/lab experiments, small descriptions of our research activities, team member’s accomplishments/awards, will be periodically updated at the blog. It also creates an open communication form among professionals, researchers, farmers, and the general public.
Areas needing additional study
- Design field-size subirrigation drainage layout that can optimize water delivery and drainage.
- Determine the optimal flow rate per acre of a water source to maximize yield.
- Design and methods of monitoring water table observation wells for farm fields.
- Find best locations for water table observation wells on farmer fields to better manage drainage and subirrigation.
- Measure evapotranspiration rates using simple and cheap methods.
- Estimate surface runoff for very flat terrain using combined field, modeling, and remote sensing approaches.
- Investigate the impact of subirrigation water quality on tile drainage system.
- Evaluate the subirrigation system performance and uniformity.
- Determine infiltration into frozen soils and into tile drained and undrained fields.