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1 Farmers Irrigation District Impact Sprinkler Conversion Project Nov 2007 by Jac le Roux – Irrinet LLC Management of Farmers Irrigation District Growers in Hood River EPA Reg 10 Grant Sandy Halstead (EPA)

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Page 1: Farmers Irrigation District - Probe Schedule › files › documents › 02a7f1c1...irrigation with impact sprinklers to irrigation on demand with micro sprinklers or drip, as scheduled

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Farmers Irrigation District

Impact Sprinkler Conversion Project

Nov 2007

by

Jac le Roux – Irrinet LLC Management of Farmers Irrigation District

Growers in Hood River EPA Reg 10 Grant

Sandy Halstead (EPA)

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Index Page

1. Project Brief 2 2. Introduction to this Report 2 3. Results 3 4. Cost 4 5. Methodology 4 6. System conversion 11 7. Data collection and Seasonal adjustments 19 8. Designers and Financial help 22 9. Summary and further ways to conserve water 23

1. Project Brief

To locally demonstrate and quantify the multiple benefits of switching from calendar-based irrigation with impact sprinklers to irrigation on demand with micro sprinklers or drip, as scheduled by soil moisture monitoring. Currently, a majority of growers use the calendar method of irrigation and approximately 25% use impact sprinklers. Similar studies indicate that impact sprinklers use 40% more water than needed to produce a crop. Negative impacts include reduction in the amount of water left in stream for aquatic life and an increase in the potential for pesticides and nutrients to leach into groundwater or runoff into neighboring waterways. This project will utilize flow meters, soil moisture data and a unique, scientifically based modeling program called Probe Schedule that makes use of real time weather, soil moisture holding capacity of the soil and crop co-efficient to calculate daily water use and project optimal dates and amounts for irrigation to be applied. Soil moisture readings are superimposed on the model to refine parameters and quantify how much water is needed by the crop and ultimately how much can be saved.

2. Introduction to this Report

This report is the culmination of a two year study paid for by grants from the EPA and NRCS. Farmers Irrigation District invited their growers to participate in this demonstration project and to commit to data collection and to conversion of a portion of their irrigation system in year 2. The cost of the conversion was subsidized by the grants. 18 growers signed up in 2006. After the first season some opted out and some did not collect any data and were eliminated. Twelve growers continued into the 2007 season of which ten did the conversion and continued to collaborate with the research. The results presented here are from those 10 growers. One of the growers agreed to do the conversion but work without a flow meter. This was done as a control to see if these results will line up with the measured details. The numbers for that grower yielded the smallest saving and I am not sure what to read into it. Since it was not checked by a flow meter, it is reported below but we did not include it in the averages. The project results were very positive and worth pursuing on a broader basis.

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3. Results In the hope of catching the eye and getting growers and planners excited about the possible savings, this report is offered somewhat back to front with the results first and the methodology and scientific detail later. Tabled below is the result for the conversion project. The results prove that at least 32% water can be saved by converting impact to micro sprinklers.

Grower code

New Irrigation System

Sprinkler gpm

2006 Total

gallons

2007 Total gal adjusted

% of Year 1 used

% Saved over

Year 1 Gal/ac Saved

2007 Use corrected

for leaching

% Saved

with no leaching

G-07 Double drip 0.017 1,065,810 456,904 42.9 57.1 608,906 334,480 68.6

E-07 Dan 2002 0.300 654,611 307,117 46.9 53.1 347,494 281,700 57.0

H-07 R10 0.770 499,064 313,992 62.9 37.1 185,072 313,992 37.1

F-07 R10 0.650 906,570 578,723 63.8 36.2 327,848 452,710 50.1

B-07 R10 0.650 542,762 350,301 64.5 35.5 192,460 350,301 35.5

I-07 R10 1.050 943,254 712,736 75.6 24.4 230,518 705,031 25.3

C-07 R10 0.890 702,884 563,244 80.1 19.9 139,640 563,244 19.9

J-07 Supernet 0.420 402,380 341,229 84.8 15.2 61,151 335,135 16.7

D-07 R10 0.650 878,585 796,023 90.6 9.4 82,562 581,888 33.8 Ave. 32.0 241,739 38.2 Control R10 0.500 604,800 559,282 92.5 7.5 45,518 45,518 7.5

Observations from the results

• The largest saving came from the conversion to double drip (57%). • The small 0.30 gpm, small radius Dan 2002 achieved a saving of 53% • There is a general trend that the smaller the discharge of the emitter (or the shorter the

radius of the sprinkler), the higher the efficiency. Grower J-07 with Supernet runs contrary to this but the number of growers was too small to be definitive.

• Although a Nelson R10 is not a true micro sprinkler it still offered substantial savings over impacts.

• Even with the leaching that occurred, these growers saved on average 241,700 gallons per acre. This is with growers converting to any sprinkler micro sprinkler.

• Over 100 acres the saving would be 24,1700,000 gallons per year – every year. • Over 1,000 acres the saving would be 241,700,000 gallons every year – for ever. • Converting to a micro like the Dan 2002 is relatively cheap and requires almost no

change to the irrigation pattern currently followed by the grower and the potential saving is a phenomenal 347,000 gallons per acre per year.

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4. Cost Growers were free to choose any design, sprinkler, designer and supplier and the costs of the conversion were highly variable. A trend emerged with the unit cost per tree being higher the lower the tree count per acre and the cost per acre being lower as the acreage increased. Tabled below is a brief summary of costs. These costs include parts, labor and trenching. System Acres converted Trees/acre $/acre $/tree

Hand line to Nelson R10 1.81 300 $1,369.60 $4.56 Solid set to Netafim Supernet 1.76 187 $1,155.43 $6.15 Hand line to R10 2.39 108 $ 673.05 $6.19 Hand line to Nelson R10 1.08 74 $1,920.84 $25.93 Project average 2.77 153 $1,261.38 $10.06

The numbers of the 74 tree/acre block is an anomaly pushing up the average cost per tree tremendously. If the economies of scale are extrapolated further the cost of conversion will probably be $1,200 per acre or $6.00 per tree, in 2007. Unfortunately the exact cost of the conversion to drip is not available but the unit cost per acre is calculated to be similar. When irrigating with drip, particularly in Hood River, filtration is imperative. An elaborate filter system will push up the unit cost. 5. Methodology

Logic model for this project is:

We need to do the demonstration project So that

We can quantify the water used by old impact sprinklers and calendar schedules So that

We can convert the same orchard to micro sprinklers and irrigate on demand So that

We can quantify the water used by the micro sprinklers So that

We can compare the impact to the micro sprinklers and quantify the water saving So that

We can motivate growers to convert impact sprinklers to modern micro sprinklers and irrigate on demand rather than by calendar.

So that Water will not be wasted or fertilizer leached into the soil profile below the root zone

So that More water is left in the streams helping the ecosystem

Growers in the Farmers Irrigation District with some impact sprinklers were invited to take part in this project. 20 responded and formed the first year study group. The experiment called for growers to, in year one, use their impact sprinklers as they normally do which includes irrigating by the calendar. However, once the experiment got under way and

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Irrinet started reporting soil moisture data it turned out that some growers were slow to get going for other reasons, which would result in lower water use but also a reduced crop. The growers also got interested in seeing their soil moisture status and started responding to it. It was then felt that it probably makes more sense to try to eliminate the variable of the grower irrigating by the calendar and concentrating on the potential saving in going from impact to another irrigation system. The procedure followed is discussed below.

Flow meters The grower had to allocate a specific orchard block or section for the trial. A flow meter was installed on the sub main feeding the specific block. Where possible the block was selected at the end of the irrigation line so that all the water registered on the flow meter went to the block specifically and no other blocks. This simplified the administration and minimized the risk of reporting irrigation that was in fact not used for this block. Since this was a demonstration project to run over 2 years we opted for the cheapest flow meters we could find, the F-1000 from Blue-White Industries Ltd., pictured below. This was not a wise decision since several of the meter malfunctioned. The manufacturer did however replace all malfunctioning units.

Fig 1. F1000 from Blue-White The other type of flow meter used, was the Aquamaster 900 from Jennings Inc. These appeared to be more rugged and performed well.

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Fig 2 Data logger of the Aquamaster 900 from Jennings

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Fig 3. Impeller housing of the Aquamaster 9000. Growers recorded the flow meter reading before and after each irrigation set. Although we need only the annual total, the individual readings were handy for interpolating data where a system failure such as pipe burst occurred. An interesting bit of side information that came out of the time vs. flow meter information is that the flow in gallons per hour was very accurate in blocks with flow regulators but not so at all in unregulated blocks. Regulate flow: Fig 4 below shows the percentage flow rate of 7 irrigation sets in a flow regulated block, along with the average (no 8) at 100%. The spread of 97% (or 3% below) to 102% (or 2% over) is excellent. The results indicate that you could use irrigation time in stead of a flow meter provided you have flow regulators in place and you are accurate with your timing. Un-Regulated flow: Fig 5 is the actual results reported by a grower with un-regulated flow. The spread of 71% (or 29% below) to 160% (or 60% over!) is alarming. Even if the grower got the timing wrong and the 160% is not for 24 hours but 48 hours, the spread is still unacceptable. This point illustrates the importance of accurate timing if you do not have a flow meter and proves that if a grower irrigates based on time without flow meter or soil moisture monitoring or flow regulation, he could be way off the mark, resulting in poor fruit development due to under irrigating or leaching due to over irrigation. The poor consistency of the un-regulated flow does not affect the results of this project since we are using the total gallons irrigated thru the season.

Delivery Spread around Average (100%) Regulated Flow

101.7

98.9

102.0

97.1

98.8

101.7

99.8 100.0

90.0

100.0

110.0

1 2 3 4 5 6 7 8

Irrigation set number

% D

eliv

ery

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Fig 4

Delivery Spread around Average (100%) No Flow Regulation

79.1

91.785.6

160.4

71.2

123.2

87.1 87.6

100.0

70.0

80.0

90.0

100.0

110.0

120.0

130.0

140.0

150.0

160.0

170.0

1 2 3 4 5 6 7 8 9

Irrigation set number

% D

eliv

ery

Fig 5

Soil moisture monitoring and irrigation scheduling To enable Irrinet to advise the grower on how much and when to irrigate (irrigation scheduling), we installed a soil moisture monitoring site in each trial block. Soil moisture monitoring was done with a calibrated CPN-503 neutron probe. (Calibration was done at MCAREC Experiment Station in Hood River and the instrument was shown to be 95% accurate between 30% and 100% moisture content). The monitoring site consists of 2 PVC (1.5”, 125 psi) tubes inserted to 36”. The tubes were carefully placed so as to be where the irrigation system wets the soil. The two tubes were placed to represent different aspects of the tree such as one east and the other west. The tubes were further places such that they will be representing two different trees, sprinklers and laterals. By graphing the moisture content per tube over time a malfunctioning sprinkler or blocked or blown line can easily be identified. See Figures 6 and 7 below.

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Fig 6. Probe tubes track each other perfectly.

Fig 7. Probe tube graphs running apart from late June (not from this project). Soil moisture readings (in Inch/foot) were then taken weekly in these tubes, at every 6” depth for a total of 12 readings per site. The moisture readings are uploaded to the Probe Schedule Irrigation scheduling software. With weekly sets of readings down the profile, a Depth graph can be constructed for each date. The wetting and drying cycle can be studied by looking at the

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graphs. Figure 8 below represents the depths graphs on 4 dates, namely September 9, 16, 23, and 30 and shows the effect of the irrigation applied during September. Read the graph as follows:

• The line at A depicts the soil moisture status on September 9. At the surface the soil is 30% depleted (of total moisture) and at 36” only 5% depleted.

• The irrigation pushes this line to B. The top 18” is flooded to almost 10% over but this water has not reached the subsoil, which has since dropped to 10% depleted.

• One week later (23 September) the evaporation and transpiration (Et) has removed some soil moisture dropping the line back to C, with the whole profile now roughly 10% depleted. In the absence of rain or irrigation the difference between the two depth graphs depicts the Et based on the weather during that time. This information is used to calculate a crop-coefficient for that crop and time phase.

• During the week 23 to 30 September, the weather turns cooler with a bit of rain and the drop from C to D is a lot smaller. With the modeling done in the program, we could accurately predict that the drop would be small.

• Even though the top soil was temporarily flooded at line B, no leaching occurred as a result because this water was intercepted by the roots before it could reach 36” and flood the subsoil.

Fig 8. Root zone soil moisture and corresponding Depth graph.

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The Probe Schedule software that was used to record the data in this project, calculates the daily soil moisture balance and irrigation schedule by making use of the following elements:

• Moisture holding capacity of the site specific soil • Root zone of the crop being monitored • Crop co-efficients representing the growth stage and canopy of the crop. • Real time weather as reflected in the Reference Evapo-transpiration value (ETO) • Inputs of rain and irrigation • Inputs of soil moisture readings.

The Probe Schedule software combines two totally different and unrelated techniques to arrive at the same answer. The first is soil water status modeling based on all the parameters listed above, except for the soil moisture readings. In the first part of the technique we calculate what the daily water consumption and resulting status should be. On the other hand, totally independently, we take a soil moisture reading and superimpose it on the model. If they match, we are confident that the modeling is good. If they do not match, we use the factual data (soil moisture reading) to refine the model until they do match. This technique can be compared to a meteorologist forecasting that it will rain 1” at a specific location tomorrow and then after the rain going to the rain gauge to see what he got. And if it is not 1”, then go back to his model and fine tune the parameters so that next time round it will be closer. Note in Fig 8 above, on the Root Zone Soil Moisture graph that the Refill line (red line) is not a straight line. During the period when the fruit is sizing, up until harvest the refill line is set to just 20% depletion. This is done to eliminate moisture stress on the tree and facilitate maximizing fruit size with balanced sugar. After harvest the refill line is dropped to 40% depletion. During this period mild stress slows down vegetative growth and stimulates new root growth, promoting tree health. During this period irrigation water can be conserved. By doing the soil moisture monitoring and irrigation scheduling, Irrinet could report to the growers and advise on the following:

• Exactly what the moisture status is, • What the effect of an irrigation set has been (too small, right or too much), • What the current rate of consumption is • When and how much to irrigate next.

6. System Conversion Each grower was free to convert their impact sprinkler system to any micro sprinkler system of their choice. Most growers opted to convert to a system similar to what they already use. One grower made the full shift and installed a double drip line with incredible saving in water use. Conversion from hand line resulted in an almost complete re-design while converting from solid set meant that the existing underground tubing could be used and added to. Below is a schematic of a typical impact sprinkler block with tree spacing of 15’ x 20’. The sprinklers are on a diamond pattern of 30’ x 40’. This kind of setup is common with old solid sets. The system is inefficient due to the large radius of the sprinklers and the dry areas formed where water does not reach effectively.

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Fig 9 Typical solid set on 30’ x 40’ diamond pattern. 6.1 Converting to Nelson R10 rotator To convert this block to a Nelson R10 sprinkler with smaller radius and discharge, the grower can use all the existing risers and convert them to hold a R10 sprinkler. To supply water to the rows in between, the grower can cut into the sub main that usually runs along one side of the block, or trench across from an adjacent lateral. In the example below (Fig 10 ) , new laterals were cut into the sub main. Note that this conversion:

• Uses all existing pipes and risers • Every other tree row gets a new poly pipe running the length of the row. • The number of sprinkler heads have been doubled. • If the discharge of the new sprinkler is no more than half of the original impact, the

supply lines will be sufficient and the same block size can be turned on. The material required is:

• Poly pipe for half the total row length. (Diameter dependent on row length). • 2 R10’s for every impact removed. • T’s and reducers to tie the new laterals into the sub main.

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Fig 10. Solid set to Nelson R10 rotator 6.2 Converting to Small radius Micro sprinkler – 1 per tree For this design conversion, the risers are used as supply points. It might be quicker and therefore cheaper to not use every riser. If the plan is to use a single riser and run the poly tube the length of the row, make sure that you do not exceed the delivery of a single riser. Note that this conversion:

• Uses all existing pipes and risers • Every other tree row gets a new poly pipe running the length of the row. • Each impact is replaced by 5 micros (including one extra at the end of each line). • The discharge of the new sprinkler should be at most 1/5 of the original impact if you

plan to use the valve sets. For example, if the impact was 2gpm (120gph), the micro should be at most 24gph.

The material required is:

• Poly pipe for half the total row length for new supply laterals. (Diameter dependent on row length.)

• Poly pipe from each riser to the middle of the next tree plus extra to reach the outside of the last tree at either end. This can be small diameter.

• 5 micros for every impact removed. • T’s and reducers to tie the new laterals into the sub main. • Converters and T’s to go on every old riser and link to poly pipe.

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Fig 11. Solid set to small micro sprinkler – 1 per tree

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Fig 12. Detail of old impact riser converted to a T for two poly tubes.

Fig 13. Small radius micro – one per tree offers excellent uniformity and good efficiency. 6.3 Conversion to Double Drip line Drip is the most efficient way of delivering water to the root zone of plants. Modern in line drip such as the Netafim RAM is pressure compensating and works from 10psi to 70psi making design easy. It is not recommended to convert mature trees from impact to single drip if the impacts are to be removed. The trees will not have sufficient roots in the wetted zone, resulting in stress and smaller fruit. If the impacts are kept in place and used as supplement, this conversion can be done. Figure 18 shows a R10 block converted to a timer controlled drip line with shut off valve on the R10 line so it can be used as supplementary irrigation and frost control. Other trials show that converting to Double Drip “cold turkey” is not a problem, even in hot dry areas such as The Dalles, Oregon. Figure 14 below is a schematic of a conversion of Impact to Double Drip. Note that this conversion:

• All risers are blocked off except one per row. • Every other tree row gets a water supply, either from the sub main or from the

adjacent row’s riser. This is feasible since the flow rate is so low. • The example impact block is 120ft long by 80ft wide and contains 12 impacts. At

2gpm, the total from in this block would be 24gpm with impact.

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• Converting to double drip of 0.5gph x 2ft = 120 emitters per row = 600 emitters in the block. At 0.5gph x 600 the flow is 300gph or 5gpm. At this flow rate a block 4 times the size of the original can be irrigated at once.

The material required is:

• Drip line for double the total tree length plus 6ft to extend past every tree row. • Poly pipe from each riser in use to the next tree row. • Plugs to seal off unused risers. • Converters and T’s to go one old riser in every row and link to poly pipe and drip

lines. (See Figure 15 for details). • A filter system to clean the water. See Figure 16 • Optional but on my wish list – a fertigation pump for liquid fertilizer.

Fig 14. Solid set to double drip line

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Fig 15. Old impact riser converted to T and T’s again into double drip lines.

Figure 16 Netafim Arkal filter with automatic pressure differential flush control.

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Figure 17 Filter to drip irrigation and timer controlled fertigation pump.

Figure 18. Dual system with Nelson R10 rotator (shut off) and a timer controlled drip line.

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7. Data collection and Seasonal adjustments This section describes how the data was collected and compiled to come up with the results reported earlier. The trial ran from May 16 to September 26 for both years. As part of the irrigation scheduling, the Daily Et (evapo-transpiration) and rainfall was obtained from the Agrimet weather station at the MCAREC Experiment Station. This is used to model the daily moisture balance but also to compare 2006 to 2007. The Reference Et (Eto) for 2006 was 31.1” translating to an average Crop Et (Etc) of 11.9” The Eto for 2007 was 33.9” translating to an average Etc of 12.3”. This means we would have to put 0.4” more water in the soil in 2007 to break even year to year. In the same way rainfall is compared. In 2006 there was 1.6” and in 2007 1.7”. The efficiency of rainfall is very low during the summer months and the resulting difference so small that it was disregarded as a seasonal variation. Another important data element is the moisture balance at the start and end of the season. Think rental car – you take it with a full tank and bring it back with a full tank. And if it is not full they want to know how much they lost (or you scored). Figure 19 below illustrates the point. The grower started the 2007 season on 7.0” moisture in the 36” root zone and ended the season on 6.1”, a loss of 0.9” In 2006 the same grower started the season on 7.0” and ended on 5.8”. Year to year that is a net gain of 0.3” over last year. That gain is due to more irrigation water applied. We will correct for that number to be able to compare system to system between the two years of the trial. These numbers are reflected in the calculations shown below.

Fig 19 Daily moisture balance graph

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Each grower participating in the trial (except the control block) had a flow meter installed on the supply line to the trial block. Before and after every irrigation set or change, the grower noted the flow meter readings. If not reset, the flow meter will display the total flow. The document submitted by Mr. Ing was clear and concise and a good way to go. It took 4 x 24 hour sets to complete the cycle. Valves were not of identical size so the gallons used and the flow rate varies, but from one cycle to the next, each valve should be close to what it was the previous cycle, and if not it could point to a problem. Using this technique a missing number can be interpolated after a pipe burst or flow meter failure. Date Time Start End Gallons Used Gph 5/29/07 7:00 P.M. 0 5/30/07 7:00 P.M. 53,294 53,294 2,220.6 5/31/07 6:30 P.M. 53,294 102,096 48,802 2,076.7 6/1/07 6:30 P.M. 102,096 154,568 52,472 2,186.3 6/2/07 7:00 P.M. 154,568 200,049 45,481 1,856.4 Total Irrigation 200,049

Deep draining or Leaching occurs when more water is added to an already full profile. Gravity cannot hold the water against gravity and the water drains to below where the roots can use it. This should be avoided because this will drain fertilizer into the sub soil from where it could find it’s way into the under lying aquifer or nearby streams. During the 2007 season, only 4 growers leached water due to over irrigation. Two of those were excessive. Any water leached is missing from our moisture balance calculation. In 2006 the average water leached per grower was 1.07” and in 2007 it was 1.63”. The grower with drip irrigation leached the most water. This is a typical reaction when someone converts to drip irrigation. Since you do not see the water on surface, you tend to put on extra just to be sure. And yes, it does mean that these growers were not responding to the soil moisture data presented to them. Leaching is identified in two ways: The Root zone moisture status graph below (Fig 20) shows a profile that was almost consistently above full capacity from mid July to late September. In this case the amount of water leached into the sub soil is calculated to be 214,000 gal/acre for the season. During this period the roots are partially an-aerobic and cannot function optimally. Fortunately this is a pear orchard. If it had been cherries, drowning might have occurred. Fig 19 on page 19 is a good example of perfect irrigation scheduling with no moisture stress and no leaching – well done Mr. Melby.

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Fig 20 Leaching can also be identified by studying the depth graph (Fig 21). The depth graph below shows a profile that is above full for a period of almost 2 weeks. During this time water leached below the root zone.

Fig 21 Since the amount of water leached is based on modeling and not direct measurement it was not included in the primary calculations. It does however imply that there is room for further water saving once the concept of irrigating on demand is fully employed.

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People looking at this report might ask what was the effect on crop yield and quality. Unfortunately the budget did not allow for that test to be included, although it would have been good. None of the growers however reported poorer yield of quality. A study on fruit yield, quality, shelf life and nutrient uptake is underway under way with Dr. Frank Yin at MCAREC. The reader is referred to Dr. Frank at [email protected] for further detail. All the number and calculations to arrive at the results reported above are in a large spread-sheet. It is available to anyone interested in scrutinizing it from either [email protected] or Jeff Cook of FID. 8. Designers, Monitoring and Financial help Every grower probably already works with a designer. If you are converting a system it makes sense to go back to the original designer as he will probably have the specs of the old system on file, making it easy to do a new design. If you are getting financial assistance from the USDA, make sure that the designer is on their list of TSP’s (Technical Service Providers). Designers that participated in this project are: Mr. Dick Radliff, Bryant Pipe, xx, Hood River Tel (541) 386 1179 Mr. Don Fessler, United Pipe & Supply, xx, Yakima, WA Tel (509) 248 9046 The soil moisture monitoring service for this project was provided by Jac le Roux of Irrinet LLC using a CPN-503 neutron probe. Growers wanting to do their own soil moisture monitoring and irrigation scheduling can choose from a number of devices. Regardless of the device selected, it is important to install the probes correctly and in the right place to get representative results. Jac le Roux offers consulting services in this regard. It is further important to see the numbers provided by your moisture probe in perspective. Integrated irrigation scheduling software is good way to record the numbers and make sense of these numbers. Listed below are some common systems, a brief description of how they work and where to get it. Financial Assistance Growers planning to convert from Impact sprinklers to a more efficient system could find financial help in a number of programs or grants. Amongst these are: EQIP – contact your local USDA office CSP

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Instrument and how it works

Installation Software Local Supplier

CPN-503 neutron probe. Bounces neutrons off hydrogen atoms.

Strictly portable. Lower into access tubes and log readings. Down load into software.

Probe Schedule Jac le Roux Irrinet LLC www.irrinet.net (541) 993 3992

Aquatel TDR probe. Data logger with telemetry link to internet data base.

Bury and connect to Automata weather station. Data logged and relayed at short intervals.

In development Mike Land (541) 993 1910 www.ifpnet.com

Watermark Granular matrix electric resistance

Bury at various depths. Hand held meter or connected to data logger

WaterGraph Bryant Pipe (541) 386-1179 www.irrometer.com

Tensionmeter Mechanical suction meter with vacuum dial

Insert into root zone at desire depth. Read dial in psi or cBar.

None Bryant Pipe (541) 386-1179 www.irrometer.com

Gro-Point Capacitance soil moisture meter. Stores data on logger with shuttle or telemetry to computer.

Bury at desired depth and connect to data logger.

Irriwise www.netafim.com

9. Summary and further ways to conserve irrigation water These techniques to conserve water are listed roughly in order of potential for saving water.

• Install efficient irrigation systems (remember – the smaller the radius the greater the efficiency)

• Monitor soil moisture and irrigate on demand • Irrigate at night • Run the profile dry at the end of he season in areas where winter rainfall is 24”+ • Use fabric or mulch cover to reduce evaporation • Install flow regulators • Install timers to control time more accurately • Repair leaky irrigation systems • Replace worn nozzles • Install flow meters and record flow data.