3.1.1 Overview of the Survey Respondents
3.1.2 Estimation of Total Irrigated Land Area in New Zealand
3.1.3 Irrigation Management Perceptions
3.1.4 Irrigation Management Practices
3.1.5 Perceived Difficulties and Limitations
3.1.6 Interpretation
3.2.1 Reasons for Irrigation
3.2.2 Water Management
3.2.3 Efficiency
3.2.4 Sustainability
3.2.5 Constraints
3.2.6 Resource Management
3.2.7 Information Sources
3.2.8 Requirements for Further Research and Information
3 Summary of Results
3.1 POSTAL SURVEY
All questions that asked farmers about how they make irrigation management decisions sought two types of answers. The first was about their actual practice, the second was about how they thought they should be making the decision. Very few farmers provided the second type of answer.
3.1.1 Overview of the Survey Respondents
The distribution by district of survey forms sent and the percent returned is shown in Table 3-1.
Overall the return rate was very good, given that the time available for the survey precluded any follow up to encourage participation. The contribution to total returns of each district is shown in percentage terms.
Table 3.1 Survey Forms Distribution and Return
| District | Surveys sent |
Surveys returned |
% of district returned |
% of total returns |
| Auckland & Waikato | 727 |
64 |
8.8 |
5.2 |
| Gisborne | 201 |
20 |
10.0 |
1.6 |
| Tasman | 309 |
57 |
18.4 |
4.7 |
| Marlborough | 383 |
97 |
25.3 |
7.9 |
| North Canterbury | 506 |
133 |
26.3 |
10.9 |
| Central Canterbury | 1036 |
193 |
18.6 |
15.8 |
| Mid Canterbury | 940 |
283 |
28.0 |
23.1 |
| South Canterbury & Waitaki |
833 |
91 |
10.9 |
7.4 |
| North Otago | 479 |
67 |
14.0 |
5.5 |
| Central Otago | 1039 |
189 |
18.2 |
15.4 |
| Unknown | 50 |
4.1 |
||
| Overall | 6453 |
1224 |
19.0 |
The type of farms represented in the survey responses is shown in Figure 3-1. Overall the majority of farms were irrigating pasture for grazing. Dairy farming was separated from other grazing enterprises, such as sheep, beef, and deer, because dairy farming typically requires higher water duties. Splitting grazing land uses in this way identifies arable cropping as marginally the largest single irrigated land use.
Figure 3.1 Occurrence of Irrigated Land Use Type in Survey Responses
Survey respondents were asked to identify which of three broad soil types is the predominant soil type on their farm – light, medium, or heavy. The number of occurrences of each type is shown in Figure 3-2. It can be seen that the vast majority of irrigated farms represented in the survey results are on light to medium soils. This is consistent with the soil types in the main irrigation areas.
Figure 3.2 Number of Occurrences of Broad Soil Types
Groundwater is the single most common source of water. However, the total number of all surface water supplies is almost equal to the number of groundwater supplies. The surface supplies include surface: storage (dams, ponds and reservoirs), surface: flowing (rivers and streams) and community supplies (from rivers and streams). The frequency of occurrence of each source is shown in Figure 3-3.
Figure 3.3 Water Sources
Travelling irrigators are the most frequently used irrigation application method amongst survey respondents. Surface irrigation systems account for only 31 percent of all application methods, by number. The number of occurrences of each application system type is shown in Figure 3-4.
Figure 3.4 Irrigation Application System Types
Responses to survey questions about the amount of water applied per season, or per irrigation, and the number of irrigation applications per season were poor. The results are not presented here because of the lack of quality. The overall impression is that farmers have little idea about how much water they are using.
The characteristics of the farms, irrigation systems, and the water sources represented by the returned surveys indicates that the responses have come from a wide cross section of irrigated farms. The distribution of responses by district, farm type, water source, and irrigator type suggest that the results of the postal survey were not significantly biased.
3.1.2 Estimation of Total Irrigated Land Area in New Zealand
Total area of irrigated land in New Zealand was estimated from the survey results and agricultural statistics. From this, the total area is estimated to be 410,000 ha, of which approximately 70,000 ha is horticultural land, 110,000 ha is arable land, 90,000 ha is dairy pasture and the remaining 140,000 ha is land used for a mixture of meat, fibre and crop production. The overall estimate is believed to be within plus or minus 10 percent.
For the ten sub-regions surveyed, the total irrigated area was estimated to be 371,000 ha. This figure was arrived at by the following method:
- The survey responses were divided between the ten sub-regions and between properties supplied from irrigation companies and private resource consents, to produce 20 categories.
- From the survey results, the average irrigated area per farm was determined for each of the 20 categories.
- From this, the total irrigated area in each category was calculated by multiplying the average irrigated area by the known number of irrigators in each category. The sum of this projection was around 490,000 ha (250,000 ha company, 240,000 ha private) which was considered to be too large.
- A first revision was made by substituting the projected company areas with the known irrigated areas for the irrigation companies. This reduced the irrigation company area to 166,000 ha or about 67 percent of the projected company area. Assuming similar overall response rates from company and private irrigators would put the total irrigated area for the ten sub-regions at 328,000 ha.
- For farms supplied by irrigation companies, it was noted that the actual average irrigated area (calculated from MAF data) varied considerably from the area calculated from the survey results, in most cases. The ratio of actual average irrigated farm area to that determined from the survey varied from 46 percent to 65 percent, except in Mid Canterbury where it was 102 percent. This variation shows that in most areas the survey responses were biased toward larger properties.
- A second revision was carried out by applying the ratios of actual to surveyed average area determined for company supplied farms to those with private resource consents. This gave a total irrigated area of 371,000 ha (166,000 ha company, 205,000 ha private).
- As a check on this figure, the area of horticulture, arable crop, dairy and other land likely to be irrigated was estimated from agricultural statistics for the ten sub-regions. These totalled to approximately 410,000 ha (35,000 ha horticulture, 110,000 ha arable, 90,000 ha dairy, 175,000 ha mixed), confirming that the 371,000 ha projection was reasonable.
As a final step, the area of irrigation outside the ten sub-regions was estimated to be around 39,000 ha. This was based largely on areas of horticultural crops (34,000 ha) and some arable crops and dairy (5,000 ha). These regions, outside the survey area, represent less than 10 percent of the total area and comprise mainly horticultural irrigation where the total areas are well known from agricultural statistics.
Table 3.1 Project Irrigated Areas in New Zealand (‘000 ha)
| Regions included in survey: | ||
| Auckland/Waikato | 6 |
1.5% |
| Gisborne | 6 |
1.5% |
| Tasman | 4 |
1.0% |
| Marlborough | 10 |
2.4% |
| North Canterbury | 30 |
7.3% |
| Central Canterbury | 79 |
19.3% |
| Mid Canterbury | 126 |
30.7% |
| South Canterbury | 45 |
11.0% |
| North Otago | 25 |
6.1% |
| Central Otago | 40 |
9.8% |
| Subtotal | 371 |
90.5% |
| Regions not included in survey: | ||
| Northland | 4 |
1.0% |
| Hawke’s Bay | 16 |
3.9% |
| Lower North Island | 7 |
1.7% |
| Rest of South Island | 2 |
0.5% |
| Subtotal | 39 |
9.5% |
| Total | 410 |
100.0% |
3.1.3 Irrigation Management Perceptions
The key decisions for operational management of irrigation are when to irrigate, how much to apply, and which crops to irrigate. Less than 23 percent of respondents said they had moderate or severe problems deciding when to irrigate, how much to apply, and which crops not to irrigate when water was short. A significant majority of farmers perceive they have no difficulties with irrigation management, per se.
The response to each of the questions which directly asked farmers to state the level of difficulty they experience in specific areas of day-to-day irrigation management are summarised in the following figure.
3.1.4 Irrigation Management Practices
Deciding when to start irrigating at the beginning of the season: Overall, 68 percent of respondents indicated that they base their decision on an inspection of soil conditions. About 24 percent said they based their decision on measured values of soil moisture. Eleven percent of respondents used an irrigation scheduling service to measure soil moisture. The measurement methods used by the remaining 13 percent who claimed to measure soil moisture are unknown.
Forty-one percent of respondents take crop condition into account and twenty-five percent take the forecasted weather into account.
The responses to the question "how do you decide when to start irrigating at the beginning of the season?" are summarised by district in the following table.
Percentage of the Total Number of Respondents (overall and by district) |
|||||||||||
Overall |
AK |
GB |
TAS |
MARL |
N.C. |
M.C. |
C.C. |
S.C. |
N.Ot |
C.Ot. |
|
| Measure soil moisture | 23.7 |
27.9 |
47.8 |
36.8 |
21.6 |
18.8 |
21.7 |
14.9 |
11.0 |
17.9 |
18.0 |
| Scheduling service | 10.7 |
0.0 |
4.3 |
5.3 |
12.4 |
12.8 |
11.8 |
17.5 |
13.2 |
13.4 |
16.4 |
| Water budget | 4.9 |
2.9 |
8.7 |
1.8 |
4.1 |
10.5 |
9.1 |
4.6 |
3.3 |
1.5 |
2.6 |
| Inspect soil conditions | 68.0 |
70.6 |
60.9 |
64.9 |
80.4 |
62.4 |
73.0 |
63.9 |
57.1 |
76.1 |
70.4 |
| Inspect crops | 41.5 |
48.5 |
52.2 |
54.4 |
60.8 |
39.8 |
45.2 |
41.8 |
28.6 |
17.9 |
25.4 |
| Weather forecast | 25.2 |
19.1 |
26.1 |
29.8 |
30.9 |
28.6 |
29.7 |
28.4 |
17.6 |
25.4 |
16.9 |
| Other | 13.4 |
13.2 |
17.4 |
15.8 |
9.3 |
16.5 |
10.6 |
9.3 |
12.1 |
11.9 |
18.0 |
| Watch neighbours | 5.2 |
1.5 |
0.0 |
5.3 |
2.1 |
7.5 |
6.8 |
9.8 |
9.9 |
4.5 |
4.2 |
Clearly farmers take a number of factors into account when deciding whether or not to start irrigation. For a clear majority of farmers, these factors are qualitative assessments of the state of the soil and crop, and how these might change with the weather.
Deciding how much water to apply: Thirty-eight percent of respondents said they do not adjust the irrigation application depth during the season or according to crop. This is consistent with responses from a related question asking how farmers decide how much water to apply. About one third responded that the application depth is fixed. Approximately one third base their decision on measured soil moisture. Overall, eight percent of respondents use irrigation scheduling services to determine irrigation application depths. Nearly 15 percent base the application depth on an estimate of how much water has been removed from the soil by evapotranspiration.
| Percentage of the total number of respondents (overall and by district) | |||||||||||||||||
Overall |
AK |
GB |
TAS |
MARL |
N.C. |
M.C. |
C.C. |
S.C. |
N.Ot |
C.Ot. |
|||||||
| Fixed by system | 33.4 |
22.1 |
21.7 |
12.3 |
18.6 |
30.1 |
54.8 |
23.7 |
42.9 |
58.2 |
49.7 |
||||||
| Do what designer said | 2.7 |
0.0 |
4.3 |
0.0 |
2.1 |
6.0 |
2.3 |
2.1 |
6.6 |
1.5 |
2.1 |
||||||
| You measure soil moisture | 27.4 |
39.7 |
39.1 |
42.1 |
26.8 |
25.6 |
19.8 |
23.7 |
15.4 |
23.9 |
17.5 |
||||||
| Estimate from ET | 14.6 |
13.2 |
21.7 |
17.5 |
20.6 |
20.3 |
15.2 |
19.6 |
7.7 |
6.0 |
4.2 |
||||||
| You use an scheduling service | 8.1 |
2.9 |
4.3 |
1.8 |
10.3 |
9.0 |
7.2 |
16.0 |
13.2 |
9.0 |
6.9 |
||||||
| Follow the neighbour | 1.6 |
1.5 |
4.3 |
1.8 |
1.0 |
1.5 |
0.8 |
2.6 |
1.1 |
0.0 |
1.6 |
||||||
| Other | 30.2 |
38.2 |
34.8 |
38.6 |
46.4 |
20.3 |
20.9 |
32.0 |
27.5 |
17.9 |
25.9 |
||||||
The proportion of farmers for whom the application depth is fixed is greater in those districts with irrigation schemes supplying water on fixed rotation for surface irrigation methods.
Deciding when to irrigate or how frequently to irrigate: Soil moisture monitoring is the most common basis for decisions about when to irrigate, or how frequently to irrigate. The proportion that uses this indicator (61 percent) is consistent with responses to the question of how to decide when to start irrigating at the beginning of the season (68 percent). Overall, about eight percent use an irrigation scheduling service to help decide when to irrigate. Imprecise wording of response options prevents assessment of how many farmers make a quantitative measurement of soil moisture conditions themselves.
| Percentage of the total number of respondents (overall and by district) | |||||||||||
Overall |
AK |
GB |
TAS |
MARL |
N.C. |
M.C. |
C.C. |
S.C. |
N.Ot |
C.Ot. |
|
| Fixed by system design | 15.9 |
4.4 |
8.7 |
8.8 |
7.2 |
25.6 |
27.0 |
16.0 |
19.8 |
22.4 |
19.0 |
| Fixed by water supply roster | 14.2 |
5.9 |
4.3 |
3.5 |
0.0 |
6.8 |
32.3 |
5.7 |
16.5 |
31.3 |
36.0 |
| Irrigation controller does it automatically | 6.4 |
16.2 |
4.3 |
10.5 |
11.3 |
5.3 |
3.4 |
1.5 |
3.3 |
3.0 |
4.8 |
| Tradition | 11.9 |
16.2 |
17.4 |
19.3 |
17.5 |
9.0 |
6.5 |
12.9 |
6.6 |
4.5 |
9.0 |
| You monitor soil moisture yourself | 52.7 |
70.6 |
69.6 |
61.4 |
51.5 |
42.9 |
52.1 |
49.0 |
38.5 |
49.3 |
41.8 |
| You use a scheduling service | 7.9 |
0.0 |
4.3 |
3.5 |
10.3 |
9.8 |
9.5 |
17.0 |
12.1 |
7.5 |
4.8 |
| Minimise labour | 10.8 |
11.8 |
4.3 |
10.5 |
5.2 |
13.5 |
9.1 |
16.5 |
12.1 |
14.9 |
10.1 |
| Other | 20.4 |
11.8 |
21.7 |
28.1 |
36.1 |
20.3 |
14.1 |
23.2 |
18.7 |
9.0 |
21.2 |
In spite of the high proportion of respondents who base their decision on soil moisture monitoring, a high proportion also claim that irrigation frequency is essentially fixed by water supply roster or system design and operation. The proportion of respondents who state that irrigation timing is fixed by water supply is highest in those districts with significant surface irrigation schemes, as expected. A significant proportion of farmers in these areas also monitor soil moisture.
Deciding Which Crops to Irrigate when Water is Short: The highest proportion of respondents base this decision on crop value (typically by dropping the lowest value crops from the irrigation cycle). It is reasonable to assume that advice from scheduling service providers, and other consultants, would also be based on crop value. Perhaps about half of farmers would therefore base this decision on crop value. A surprising number continue on with their standard irrigation routine regardless of crop value. This is a little more common in districts with surface irrigation schemes and probably reflects the predominance of pastoral farms in these schemes.
| Percentage of the Total Number of Respondents (overall and by district) | |||||||||||||
Overall |
AK |
GB |
TAS |
MARL |
N.C. |
M.C. |
C.C. |
S.C. |
N.Ot |
C.Ot. |
|||
| Drop low value crop | 29.5 |
22.1 |
17.4 |
35.1 |
15.5 |
36.8 |
45.2 |
39.7 |
25.3 |
34.3 |
23.3 |
||
| Irrigate best crops first | 8.5 |
4.4 |
4.3 |
3.5 |
2.1 |
9.0 |
16.0 |
9.8 |
11.0 |
13.4 |
11.1 |
||
| Ask advice | 5.3 |
5.9 |
0.0 |
3.5 |
3.1 |
7.5 |
13.7 |
8.8 |
6.6 |
1.5 |
2.6 |
||
| Water budgets | 10.1 |
10.3 |
4.3 |
17.5 |
9.3 |
15.0 |
14.1 |
8.2 |
6.6 |
6.0 |
9.5 |
||
| Scheduling service | 5.0 |
1.5 |
4.3 |
1.8 |
4.1 |
6.0 |
7.2 |
13.4 |
5.5 |
4.5 |
1.6 |
||
| Carry on regardless | 16.1 |
13.2 |
21.7 |
10.5 |
13.4 |
10.5 |
16.7 |
14.9 |
18.7 |
19.4 |
22.2 |
||
| Other | 21.0 |
23.5 |
34.8 |
17.5 |
24.7 |
18.0 |
19.0 |
24.2 |
20.9 |
9.0 |
18.5 |
||
Deciding whether to stop irrigation after rainfall: A significant majority of respondents claim to base their irrigation decisions immediately after rainfall on an assessment of the effects of the rain. Very few of the respondents carry on irrigating regardless of the amount of rain.
| Percentage total surveyed actual | |||||||||||
Overall |
AK |
GB |
TAS |
MARL |
N.C. |
M.C. |
C.C. |
S.C. |
N.Ot |
C.Ot. |
|
| Measure rainfall amount | 52.5 |
36.8 |
34.8 |
54.4 |
63.9 |
56.4 |
61.2 |
67.0 |
57.1 |
47.8 |
46.0 |
| Monitor soil moisture | 57.4 |
63.2 |
73.9 |
64.9 |
55.7 |
49.6 |
58.2 |
55.2 |
53.8 |
55.2 |
43.9 |
| Stop for 1 week if 50 mm or more of rain | 19.4 |
13.2 |
26.1 |
14.0 |
20.6 |
22.6 |
18.6 |
17.0 |
23.1 |
23.9 |
15.3 |
| Irrigate regardless | 10.3 |
4.4 |
0.0 |
1.8 |
7.2 |
13.5 |
17.9 |
6.2 |
8.8 |
14.9 |
28.0 |
| Watch neighbours | 1.3 |
0.0 |
0.0 |
0.0 |
0.0 |
1.5 |
3.0 |
1.5 |
4.4 |
1.5 |
1.1 |
| Other | 10.6 |
17.6 |
4.3 |
8.8 |
13.4 |
7.5 |
13.3 |
12.9 |
6.6 |
7.5 |
13.8 |
3.1.5 Perceived Difficulties and Limitations
A series of questions were asked to obtain farmers views of what factors limit their ability to manage their irrigation systems as effectively and efficiently as they would like to. The questions were a mix of guided response and open-ended questions.
In general, and as reported above, few farmers perceive they have problems with deciding when to irrigate and how much to put on (determinants of efficiency). The most frequently cited problem is with water supply. There are two aspects to this: the capacity of the on-farm system and the reliability of supply (from rivers and schemes). The first is a matter of design and the second is a matter of river management. The effect of both problems is to limit farmers’ ability to apply water in the amounts they believe are necessary for crop production. The primary issue is effectiveness (production), not efficiency.
A large number of farmers cited windy conditions as posing a significant difficulty in managing irrigation effectively and efficiently.
Responses to this group of questions revealed one over-riding longer-term concern. This is on-going access to the water resource they currently use. The concern is that access to water will be lost, or significantly reduced, when application is made to renew permits to take water under the Resource Management Act.
When asked what they see are the main limitations on their ability to improve irrigation management the most frequently cited moderate or severe limitation was cost, or lack of profit (60 percent). System capacity (35 percent), irrigation system type (33 percent), and water supply (33 percent) followed this. It is interesting to note that "cost" was not included as a response option in the questionnaire – it was volunteered by respondents.
3.1.6 Interpretation
Technically, efficient irrigation requires a quantitative measure of how much water can be stored in the root zone, without drainage, immediately prior to irrigation. This can be done directly, by measuring soil moisture content, or indirectly, by measuring evapotranspiration and calculating how much water has been removed.
Effective irrigation requires that irrigation be timed so that plants are not stressed. Again, this requires routine measurement of soil moisture of evapotranspiration.
Given this, the proportion of farmers who are potentially able to efficiently and effectively manage irrigation, because they apparently obtain the hard data that is needed, is:
Irrigation timing: about 40%
Irrigation amount: about 50%
These figures are unexpectedly high.
Very little equipment is available on the NZ market for routine soil moisture measurement on-farm. Industry opinion is that the number of tensiometers and other instruments in use for soil water measurement are significantly less than those using scheduling services.
Respondents in some districts claim to use irrigation scheduling services when industry sources state that commercial scheduling services are not yet available in those districts.
The survey results leave the impression that a large majority of farmers know that soil moisture and evapotranspiration data is the basis of good irrigation management but that for most the monitoring is qualitative. It is likely that respondents included visual inspection in "measurement" and "monitoring". The conclusion is that between 10 percent and 12 percent of respondents regularly measure soil moisture.
Overall, for about one third of the respondents, a fixed amount of water is applied each irrigation. In those areas where there are large surface irrigation schemes, the proportion exceeds 50 percent. In these areas the frequency of irrigation is fixed by system design or the supply roster, in excess of 50 percent of cases. The combination of fixed frequency and fixed application depth is internationally accepted as the environment least conducive to efficient irrigation.
3.2 FOCUS GROUPS
From the focus groups a set of common themes emerged which were used to derive a set of headings under which the outcomes are reported. These headings are:
- Reasons for irrigation
What were farmers’ objectives when installing irrigation or buying irrigated land? Had these objectives changed or were they still being met?
- Water Management
How was water being managed and scheduled?
- Efficiency
What did irrigators understand by irrigation efficiency and what were they doing to ensure water was used efficiently?
- Sustainability
What did irrigators understand by sustainability of irrigation practices?
- Constraints
What constraints effected water management practices, efficiency and sustainability of irrigation?
- Resource Management
What were the local issues particularly in relation to access to water resources, council policies, etc?
- Information
Were did farmers get information from on issues related to irrigation and how useful was it?What requirements were there for new technologies and information?
- Requirements
Details of the outcomes for each focus group can be found in the Appendix I. Overall findings of the focus groups are summarised in the following sections.
3.2.1 Reasons for Irrigation
Most pastoral farmers originally invested in irrigation as insurance against drought conditions, thus avoiding being "weak sellers" and enabling pasture improvement. Several irrigators raised doubts about the economic benefits of developing new irrigation for grass, except for dairy.
Partial irrigation allows pastoral farmers to improve the potential of their dryland blocks.
Irrigation has allowed pastoral farmers to diversify into arable farming and process cropping.
Irrigation is believed to be essential for successful process cropping and horticulture.
Without irrigation it would be impossible to get a contract to grow process crops.
Irrigation maximises the return on other inputs such as fertiliser, labour and fuel.
Irrigation improves quantity, quality and consistency of crop yield
3.2.2 Water Management
Water management techniques tend to be concentrated at two ends of the spectrum.
Soil moisture monitoring services, using neutron probes and TDR, are used by some "top end" growers where available (Nelson, Marlborough, Canterbury). It mainly used on farms irrigating higher value crops (grapes, process vegetables, and some arable crops). Some orchardists are successfully using tensiometers for water management.
The vast majority of irrigators are relying on visual inspection of crops, soil, the weather, and what the neighbours are doing to manage their irrigation systems. Many irrigators are unaware of water budgeting techniques or have insufficient access to the necessary data.
Most irrigators are constrained in the management of their systems by the availability of sufficient water at critical times due to factors such as:
- Fixed rosters in some community owned schemes;
- Insufficient flows in some community owned schemes to operate borders properly;
- Low flow restrictions in surface water bodies;
- Low water level restrictions on some groundwater aquifers;
- Inadequate irrigation plant to keep up with true irrigation demand;
- Total loss of water source in late summer in some drier areas.
Very few irrigation systems, except centre pivots, linear moves and well designed trickle systems, have the capacity to apply water "little and often" even though this is recognised as the ideal.
Irrigators adopt a number of strategies to work around these constraints:
- Always start earlier than necessary;
- don’t stop even when it rains;
- always water when water available in roster;
- water most valuable crops first.
3.2.3 Efficiency
Efficiency of irrigation was defined in various ways including:
- avoiding wastage by visible runoff;
- not irrigating in the wind or during the day when evaporation is high;
- avoiding over-watering resulting in water-logging;
- minimising the water input to achieve a desired result;
- Maximising the return on the cost of water (either real cost or cost of energy to pump);
- minimising labour input;
- maximising the return on other inputs such as fertiliser, fuel and labour.
Many growers compared the efficiency of different irrigation systems including:
border strip versus spray big guns versus booms; sprinklers versus trickle (drip); contour irrigation versus big guns. Within community owned systems there was discussion about the effect of fixed rosters (easier to manage but less efficient).
The "take or lose" policies on water rights practised by some regional councils were perceived to be having a negative effect on water use efficiency.
In some cases, the cost of more water is less than the cost of improving system efficiency.
Inability to accurately predict rainfall is a limiting factor in efficient use of irrigation water in a wet season.
3.2.4 Sustainability
Irrigators concepts of sustainability varied widely. Sustainability is becoming a "dirty word" in some areas where irrigators feel that the actual implementation of the RMA is quite different to what they expected.
Most irrigators where primarily concerned about the economic sustainability of irrigated agriculture and believed that getting the economics right would involve a number of factors of which environmental sustainability would be only one.
Most irrigators consider that they are farming in a sustainable manner within the limits of their financial and physical resources.
A common concern was for the sustainability and continued accessibility of water resources for irrigation. Threats to this include:
- urban expansion without proper planning for potable water needs and subsequent loss of water for agriculture;
- increasing pressure from lifestyle blocks with unrestricted access to groundwater;
- unrealistic expectations of conservationists and recreational users particularly anglers;
- competition for water from forestry processing plants;
- forestry planting on aquifer recharge zones;
- district and regional plans that do not recognise the importance of agriculture and horticulture in regional economies;
- competition between different agricultural uses and users in different areas for the same resource.
Some concern was expressed about the effect of irrigation on soils including:
- salinity in some limit areas;
- soil structure under big guns.
Concern for leaching and runoff of nutrients (particularly nitrogen) was not considered to be a significant problem, except for dairy farms.
Very few irrigators thought in terms longer than their own life time. In general sustainability of irrigation is not high on farmers list of priority issues, except where access to water resources is limited.
The lack of an obvious next generation of farmers was given as a reason for not investing in irrigation developments in some areas.
3.2.5 Constraints
Many irrigators feel constrained in their ability to manage irrigation effectively due to the limited capacity of their systems -- both private on-farm systems and off-farm community supplies. System design flows are inadequate for present requirements due to original under-design, or expansion of demand beyond original intentions. Most irrigators would like to improve the efficiency of their system but are constrained by a combination of:
- a lack of finance to upgrade systems;
- unsuitable topography (too hilly for booms or centre pivot);
- unsuitable farm layout (irregular boundaries and roads, small lot sizes);
- lack of water availability on demand;
- meteorological factors such as wind;
- lack of suitable equipment;
- lack of time.
In areas where water resource development is required to meet demand (e.g. water storage, river enhancement and aquifer recharge) irrigators feel constrained by the excessive "red-tape" required to work through the RMA consents process.
Soil characteristics, particularly infiltration rates and water holding capacity, can be severe limiting factors.
General uncertainty within the agricultural sector regarding prices and markets is preventing investment in on-farm improvements and off-farm development
3.2.6 Resource Management
The primary resource management issues relate to tensions between irrigators, regional councils and other water users over the allocation of water. In Auckland irrigators are dissatisfied with obvious variations in policy between Environment Waikato and ARC, increasing "red-tape" and RMA compliance costs. In Nelson irrigators are suspicious of the motives of the TDC and Nelson City over Tradeable Water Permits. In many areas of Canterbury there is general dissatisfaction with the performance of the CRC and its apparent dominance by urban councillors from Christchurch with little understanding of rural issues. Irrigators in Marlborough and Otago seem less concerned with resource management issues but are watching to see what will happen in neighbouring regions.
Commonly raised issues include:
- the decreasing political power of rural communities;
- the increasing power of recreational lobby groups to prevent individual irrigators and schemes accessing water;
- increasing RMA compliance costs being placed on land owners without being able to pass these costs on to consumers;
- lack of recognition within district and regional plans of the economic multiplier effect of irrigated agriculture within regional economies;
- increasing urban encroachment and rural subdivision without proper planning for potable water supplies that result in over allocation of resources and loss of irrigation;
- lack of experience of council staff with respect to rural issues and practical operation of irrigation systems resulting in policies that are often unworkable and sometimes lead to the opposite effect to that desired (eg increased water consumption resulting from "take or lose" policies);
- there is a commonly held belief among irrigators that they are perceived by urban residents as the environmental "bad guys";
- water meters are seen to be a useful tool in areas with water resource limitation but moves to introduce charging would be vigorously resisted;
- many irrigators believe that there is insufficient knowledge of water resources and that Councils allocation polices are ill founded.
3.2.7 Information Sources
Irrigators obtain information from a number of sources depending on location. Irrigators in "advanced areas" such as Auckland, Nelson, Marlborough and Canterbury are generally well informed through their own research, by consultants and irrigation equipment suppliers. In more remote areas, particularly Otago, the level of information available is low with farmers relying on their own experience or that of their neighbours. The standard of information available from Regional Councils was perceived to be generally poor, outdated and inappropriate.
3.2.8 Requirements for Further Research and Information
Some common themes to emerge included:
- better information on water resources;
- better weather forecasts;
- consultation between irrigators, councils and other water users;
- new crops to increase economic return on irrigation;
- more information on comparisons between different systems;
- systems with lower labour requirements;
- regional water development plans including storage and stream augmentation;
- information on techniques to improve water use efficiency.
Contact for Enquiries
MAF Information Services
Pastoral House
25 The Terrace
PO Box 2526
Wellington, NEW ZEALAND
Fax: +64 4 894 0721
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