Perceptions of Irrigation Water Management Practices in the Mississippi Delta

Abstract

The Mississippi River Valley Alluvial Aquifer (MRVAA) is being depleted, and practices that improve water stewardship have been developed to reduce drawdown. This study assesses how Mississippi Delta producers changed their perceptions of these practices over time. The analysis employs data from two surveys carried-out in 2012 and 2014 of all Mississippi permittees who held an agricultural well permit drawing from the MRVAA. Focusing on water-saving practices, this study found that producer perception of the usability of flowmeters improved over time. About 80% and 90% more producers growing corn and soybeans, respectively, felt that computerized hole selection was highly efficient. In 2014, 38% of corn and 35% of soybean producers believed that shortened furrow length was a highly efficient practice—up from 21% in corn and 24% in soybean producers in 2012. Approval of irrigation automation, moisture probes, and other irrigation technology rose from 75% of producers in 2012 to 88% by 2014. Favorability toward water-saving practices increased overall between the survey years.

1. Introduction

The Mississippi River Valley Alluvial Aquifer (MRVAA) encompasses parts of Mississippi, Arkansas, Louisiana, and the bootheel of Missouri (Figure 1). While water resources are seemingly abundant, the MRVAA is being depleted at an alarming rate, due primarily to agricultural use [1]. The area overlying this aquifer, known as the Mississippi Delta, is typified by flat, fertile, farm ground. More than 40% of these acres are irrigated [2]. About 80% of those irrigated acres are gravity flow systems—typically furrow irrigation delivered by flat polyethylene tubing [3]. While other irrigation methods, such as sprinkler irrigation, can reach application efficiencies over 85%, the application efficiency of furrow irrigation is usually a mere 65% [4,5,6]. Despite the inefficiency of furrow irrigation, this practice has remained popular in the Mississippi Delta because of the flat topography, infrastructure, and access to seemingly abundant water resources. Since other forms of irrigation in the Mississippi Delta are decreasing, it is apparent that furrow irrigation will not be abandoned for more efficient irrigation methods in the future [2].

It is important, therefore, that water-conserving management practices in furrow-irrigated systems be utilized. Extension, education, and research efforts have been employed to provide agricultural producers with the most efficient irrigation methods. Practices have been developed to improve the water application efficiency of furrow irrigation [7]. Shortening the length of run, land leveling, utilizing a computerized hole selection program (CHS) or Pipe Hole and Universal Crown Evaluation Tool (PHAUCET), surge valves, soil moisture sensors (SMS), and automation are a few of the practices that can increase irrigation efficiency [8,9]. Practices such as flowmeters, SMS, surge irrigation, and computerized hole selection were actively promoted by state Extension services in the Delta in the early 2010s [3,10,11,12]. Studies have found that positive perceptions of water saving practices lead to water-saving behaviors [13,14]. In 2012 and 2014, a survey was deployed to gauge the perception of these management practices. The changes in perception from 2012 and 2014 expectantly represent the effectiveness of education and Extension efforts. It is hypothesized that producers’ perceptions of metering, computerized hole selection, shortened furrow runs, and scheduling and automation changed between 2012 and 2014. The purpose of this study was to document the changes in perceptions of Mississippi Delta irrigation water use permitholders regarding irrigation practices between the years 2012 and 2014 upon which future studies and investigation can be based.

2. Materials and Methods

The questionnaire was administered to Delta residents who held irrigation water use permits. They were classified as landowners, landowners and operators (producers), or operators who withdrew surface or groundwater for agricultural irrigation in the Mississippi Delta region. A contact list was retrieved from the Permit Database from the Department of Land and Water at the Mississippi Department of Environmental Quality. By surveying the entire population, the study was deemed a census, and therefore did not require a model-based or design-based inference.

The questions were developed during multiple interviews and focus groups where producers, stakeholders, and interested parties provided input regarding water resource concerns in the region. The preliminary questionnaire was tested and modified to avoid bias based on wording, order or other suggestive indications; resulting in 64 final questions—of which 8 deal with IWMs. The final questionnaire was used in telephone interviews conducted by the Survey Research Laboratory at Mississippi State University during November and December in 2012 and November through February in 2014–2015. Personal identifiers were not recorded or reported for the 2012 or 2014 surveys to protect the survey respondents. Researchers were unable to compare responses from individuals between years but were comparing responses from all respondents. A total of 460 completed responses were achieved in 2012 and 311 in 2014 (see

Table 1. Explanation of all possible categories for each telephone number in the population for 2012 and 2014.

	2012	2014
Surveys completed	460	311
Respondents refused interview	120	104
Requested callback but could not be contacted prior to end of survey	48	59
Respondent out of town for the duration of the survey	14	5
No answer/busy signal/voicemail	314	296
Communication problem/language problem/other issue	26	40
Respondent no longer held a permit for an agriculture well	133	6
Respondent deceased or unable to participate due to health problem	68	30
Duplicate owner/operator	88	36
Disconnected number/no longer in business	606	325
Official sample 1	1789	1176
Cooperation rate 2	79.3%	74.9%

¹ Total telephone numbers minus duplicate owner/operator. ² $\mathrm{Cooperation}\mathrm{rate}=\frac{\mathrm{Completed}\mathrm{surveys}}{\mathrm{Completed}\mathrm{surveys}+\mathrm{Respondent}\mathrm{refused}\mathrm{interview}}\times 100\%$.

for breakdown of attempts to reach 1877 contacts in 2012 and 1212 in 2014).

This study examines the change in perception and attitudes of water-saving management practices during the time between the administration of the two surveys. These questions and the response choices can be viewed in

Table 2. Question Wording and response set.

Question	Response Set	df	p > F
Water meters are the best way of measuring irrigation use. (level of agreement)	Strongly disagree Disagree Neither disagree nor agree Agree Strongly agree	4	<0.0001
Putting meters on wells will ultimately lead to taxes or fees on water used. (level of agreement)	Strongly disagree Disagree Neither disagree nor agree Agree Strongly agree	4	0.023
PHAUCET 1 program for sizing holes for furrow irrigation (level of efficiency for irrigating soybeans)	Highly efficient Efficient Inefficient	2	<0.0001
PHAUCET program for sizing holes for furrow irrigation (level of efficiency for irrigating corn)	Highly efficient Efficient Inefficient	2	<0.0001
The PHAUCET program should be used on every furrow irrigation system. (level of agreement)	Strongly disagree Disagree Neither disagree nor agree Agree Strongly agree	4	<0.0001
Short irrigation runs (level of efficiency for irrigating soybeans)	Highly efficient Efficient Inefficient	2	0.046
Short irrigation runs (level of efficiency for irrigating corn)	Highly efficient Efficient Inefficient	2	0.001
Automated irrigation metering, soil moisture probes, rain gages, and other technology is the future of irrigation in the Delta. (level of agreement)	Strongly disagree Disagree Neither disagree nor agree Agree Strongly agree	4	<0.0001

¹ Pipe Hole and Universal Crown Evaluation Tool (computerized hole selection).

—the same questionnaire was used both times. Data were analyzed using the Statistical Package for Social Sciences (SPSS). Summary statistics for the producer demographic are shown in

Table 3. Land ownership and crop production of those who completed the survey in 2012 and 2014.

	2012	2014
Landowners (not actively farming)	37.8%	30.5%
Landowner and Operators (owning land and actively farming)	51.5%	58.5%
Operators (actively farming, not owning land)	10.7%	10.9%
Grow and Irrigate Corn	78.7%	66.7%
Grow and Irrigate Soybeans	95.8%	96.3%
Grow and Irrigate Rice	36.0%	36.6%
Grow and Irrigate Cotton	30.8%	21.8%
Grow and Irrigate Other Crops	26.0%	21.3%

. Demographics such as age were not collected in this dataset. Chi-square tests were used to determine whether a statistically dependent relationship exists between the responses to each survey item and the survey’s year of administration. Responses at an alpha level of p < 0.05 were considered significant.

3. Results

In 2012, 460 telephone surveys were completed; 311 were completed in 2014. Only 120 and 104 respondents refused the interview resulting in cooperation rates of 79.3% and 74.9% for 2012 and 2014, respectively (Table 1). Of the two survey periods, most respondents reported owning land and actively farming (Table 3). More growers produced soybeans and corn than any other crop during both years.

3.1. Flow Meters

In response to the statement “water meters are the best way of measuring irrigation use. (level of agreement)”, respondents could choose strongly agree, agree, neither agree nor disagree, disagree, or strongly disagree. Most respondents in both years either agreed or strongly agreed with this statement (

Table 4. Water meters are the best way of measuring irrigation use. Responses were statistically different (p < 0.0001) between 2012 and 2014.

		------------% Respondents----------		Percentage Point Change
		2012	2014
Water meters are the best way of measuring irrigation use. (level of agreement)	Strongly Agree	2.9	10.3	7.4
	Agree	49.4	58.4	9.0
	Neither agree nor disagree	8.5	7.9	−0.6
	Disagree	32.0	20.6	−11.4
	Strongly disagree	7.3	2.7	−4.6

). In 2012, a large portion of the respondents disagreed or strongly disagreed with the statement. However, an increase in positive (agree or strongly agree) responses was observed in 2014. The percentage of those who strongly agreed to this statement increased more than threefold, and those who agreed also increased by 9.0 percentage points in 2014. This occurred while those who disagreed with this statement decreased by 35%, thereby, signifying a shift toward believing that water flow meters are the best way to measure irrigation water use.

Respondents were also asked about their level of agreement to the statement “putting meters on wells will ultimately lead to taxes or fees on water used.” Those who strongly agreed with this statement increased over the two years by 30% (

Table 5. Putting meters on wells will ultimately lead to taxes or fees on water used. Responses were statistically different (p = 0.023) between 2012 and 2014.

		------------% Respondents----------		Percentage Point Change
		2012	2014
Putting meters on wells will ultimately lead to taxes or fees on water used. (level of agreement)	Strongly Agree	24.3	32.0	7.7
	Agree	59.8	49.3	−10.5
	Neither agree nor disagree	2.8	5.1	2.3
	Disagree	11.4	10.5	−0.9
	Strongly disagree	1.6	3.1	1.5

). This shift in perception came as those who simply agreed with this statement decreased by 10.5 percentage points between the two years, indicating a shift in perception from agree to strongly agree.

3.2. Computerized Hole Selection

Respondents were asked to rank the “PHAUCET program for sizing holes for furrow irrigation” as highly efficient, efficient, or inefficient. In 2012, 64% of respondents believed that using the PHAUCET program for sizing holes for furrow irrigation in corn was efficient, 30% believed this practice was highly efficient, and only 6% believed this practice was inefficient (Figure 2). While little change occurred in those who perceived this practice as inefficient, there was a change in the percentage selected efficient or highly efficient. Those who found this practice highly efficient increased from 30 to 55%. This change signifies a shift in belief that this practice is efficient to belief that it is highly efficient. Very similar changes occurred between the two years for soybeans, and those that found this practice inefficient decreased by more than half.

Respondents were asked their level of agreeance to the statement “The PHAUCET program should be used on every furrow irrigation system.” Respondents could choose strongly agree, agree, neither agree nor disagree, disagree, strongly disagree. In 2012, 3.7% of respondents strongly agreed that computerized hole selection should be used on every acre, 43.2 % agreed, 11.6% remained neutral, 38.6 disagreed, and 2.9% strongly disagreed with this statement (

Table 6. Utilizing the PHAUCET program on every furrow irrigated acre. Responses were statistically different (p < 0.0001) between 2012 and 2014.

		------------% Respondents----------		Percentage Point Change
		2012	2014
The PHAUCET program should be used on every furrow irrigation system.	Strongly Agree	3.7	16.8	13.1
	Agree	43.2	48.5	5.3
	Neither agree nor disagree	11.6	5.6	−6
	Disagree	38.6	25.0	−13.6
	Strongly disagree	2.9	4.1	1.2

). In 2014, there was a shift from disagree to agree and strongly agree. Those who disagreed fell by more than 13 percentage points, while those who agreed rose by 5.3 percentage points. Those who strongly agreed grew 4.5-fold, thus increasing to 16.8%.

3.3. Length of Run

Respondents were asked to rank the efficiency of “short irrigation runs” in corn and soybean production. Most consider this practice efficient across both years and both crops. In 2012, 21% and 24% of producers viewed this practice as highly efficient for corn and soybeans, respectively (Figure 3). A change in perception was observed between the two years. Those who considered this practice efficient decreased by 18% in corn and 8% in soybeans, showing a shift in perception from efficient to highly efficient. The largest shift was experienced in corn, with a 17% increase in those who found the practice highly efficient. The perception of efficiency in soybeans changed but in less magnitude. With that crop, those who found short runs highly efficient rose by 11%. No detectable change occurred among those who found this practice inefficient.

3.4. Irrigation Scheduling and Technology

Responses to the statement, “Automated irrigation metering, soil moisture probes, rain gauges, and other technology is the future of irrigation in the Delta” differed between 2012 and 2014. In 2012, 7.0% strongly agreed, 68.1% agreed, 7.4% neither agreed nor disagreed, 15.9% disagreed, and 1.5% strongly disagreed (

Table 7. Perceptions of the future of automation, soil moisture probes, and other technology. Responses were statistically different (p < 0.0001) between 2012 and 2014.

		------------% Respondents----------		Percentage Point Change
		2012	2014
Automated irrigation metering, soil moisture probes, rain gages, and other technology is the future of irrigation in the Delta. (level of agreement)	Strongly Agree	7.0%	17.1%	10.1%
	Agree	68.1%	70.5%	2.4%
	Neither agree nor disagree	7.4%	4.3%	−3.1%
	Disagree	15.9%	8.1%	−7.8%
	Strongly disagree	1.5%	0.0%	−1.5%

). There was a greater than 2-fold increase in 2014 in those who strongly agreed that these technologies were the future of irrigation. Those who agreed only slightly grew by 2.4 percentage points. Those who disagreed decreased by approximately half. Fewer people felt neutral, disagreed, or strongly disagreed in 2014 than in 2012.

4. Discussion

This study assesses the change in perception of practices among irrigation well permit holders in the Mississippi Delta from questionnaires administered in 2012 and 2014. The focus of this census was to gauge the effectiveness of Extension education and outreach activities promoted between the two years. The data shown here are representative of effective outreach in these areas.

Between 2012 and 2014, flowmeters were promoted by Extension personnel in most of the states surveyed [3,9]. Therefore, it is not surprising that as producers were educated, their perception of the best irrigation water measuring technique trended towards using flow meters. Several methods exist for measuring water flow, such as: direct measuring, propeller flow meters, weirs, flumes, orifices, etc. [3]. Most of these methods are inaccurate, time consuming, or inapplicable for furrow irrigation systems common in the Delta. By default, producers increasingly consider flow meters the best fit for the pump-to-polyethylene pipe delivery system.

Despite the increasing belief that irrigation water is best measured with flow meters, there may be reluctance in adopting this practice out of concerns it could lead to taxation or fees. While most producers and landowners agreed on the usefulness of meters for measuring water, the fact that 81% either agreed or strongly agreed that this action could ultimately lead to taxes or fees on water used reveals potential reluctance to implement this practice.

The increase in favorability of CHS among corn and soybean producers is likely indicative of successful Extension and education efforts. The strong shift towards agreeing or strongly agreeing to the statement “the PHAUCET program should be used on every furrow-irrigated acre” also indicates that CHS programs are becoming more popular (Table 5). However, since 29.4% of producers still either disagree or strongly disagree, there may still be some reluctance to adopt CHS. The indication of a required use of a computer application is one likely reason why there were some who disagreed, but computer use proficiency or accessibility was not assessed in this study. However, CHS is still actively promoted despite this disinclination, so reluctance is expected to continue decreasing in subsequent years. CHS programs are considered one of the simplest upgrades that can be implemented on a furrow irrigated system [15,16]. The program is free, and, aside from a flow meter to measure flow, no additional tools or infrastructure are needed. It offers several other advantages as well. Reduced run time, less water runoff, water savings, and application uniformity make this practice increasingly attractive. These advantages can result in water savings from 20 to 50% depending on the shape of the field [15]. Because of the extremely low cost of entry and the ease of implementation, it is no surprise that a shift in perception has ensued.

Reduced irrigation time, water savings, and uniform irrigation are all possible explanations for the increase in favorability of shortening furrow run distance. The time it takes for water to travel is exponentially proportional to the distance down the furrow [17]. The length of run should be fitted to the soil type, slope, and the flow furrow-1 [18]. In many cases, this means decreasing furrow distance, especially in large fields. Excessive deep percolation can occur at the top of the field when furrows are too long. However, researchers also agree that water can be wasted when furrow distance is too short due to excessive runoff required to achieve acceptable percolation [17,18]. The USDA offers equations and parameters to devise the correct distance of the furrow irrigation system [18]. Some producers responded that shortened runs were inefficient. This sentiment is most likely linked to the extra cost to implement this practice. To shorten furrow run distance, fields may require re-leveling, extra ditches, and additional irrigation equipment. Shortened runs also increase labor costs associated with irrigating. Those two costs may discourage producers from adopting this practice.

Respondents are increasingly looking toward automation, metering, SMS, and other technologies in the future. Table 7 shows that the number of respondents who strongly agreed more than doubled; this suggests that receptiveness to these technologies is increasing. Currently, Mississippi Delta producers rank third compared to other watersheds in their use of SMS with an adoption rate of 16%, and Mississippi producers are ranked second highest in the nation for SMS use with a 27% adoption rate [2]. This is a dramatic improvement since 2013 where only 11% of Mississippi producers used SMS, and only 7% used SMS Delta-wide [19]. The use of SMS and other technologies is only expected to increase as Extension and outreach activities continue.

5. Conclusions

Over time, producers’ perceptions of metering, computerized hole selection, shortened furrow runs, and scheduling and automation trended towards more favorability of these practices. This study indicates that efforts, funding, and research have been successful in influencing producers to make more water-wise management decisions. There is still room for improvement in some areas of this study. These results will also be useful in identifying areas where outreach was successful as well as areas that need more improvement. Further research and Extension projects are needed to continue increasing the favorability of these water-saving practices. Research, extension, and outreach activities may also improve water savings when focused on other high water use crops not mentioned in this study, such as rice and cotton.