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I-60 Case Study: How the Hunter Low Pressure Specialist Can Save You Money
 At municipal sites across the land, park superintendents are finding that a retrofit to the Hunter I-60 can provide the cost saving alternative to adding a booster pump to a site that already has commercial-grade rotors installed. Likewise, those dealing with first-time installations are finding it’s a no-brainer to choose the I-60 over other rotors that just can’t match the Hunter products for its ability to perform and penny-pinch at the same time.
What makes the I-60 so efficient in operating with low water pressure is its single-nozzle design that features Hunter’s patented Precision Distribution Control™ for reduced turbulence and maximum radius. As gear-driven pins intermittently diffuse the stream it results in water-efficient performance and the absolute minimum of runoff and waste.
The I-60 also boasts six color-coded nozzles for truly uniform coverage and fast identification, easy arc adjustment from 40°-360°, as well as Hunter’s VStat® self-adjusting stator and a stainless steel riser for increased durability in harsh soil conditions.
To demonstrate the cost savings that the I-60 rotor can provide, we offer two different examples where low water pressure plays a key role in the decision making process. In the first example, an existing community park has seen its water pressure steadily drop over the years as surrounding development has increased. In the second example, a city is trying to determine which size rotor makes the most sense to install in a new park.
Retrofit Installation
Existing 2.5 Acre City Park
SITUATION: Five years after the original system installation at the site, the zone pressure drops to 40 psi dynamic, due to a substantial increase in surrounding housing density. The entire irrigation system at the park is currently under-performing due to the lower operating pressure.
The city is considering one of two options as a solution:
- Booster pump to increase pressure at the park
- Hunter I-60 rotors as a replacement for existing rotors
CONCLUSION: In this example, the clear winner is the system retrofitted with I-60 rotors. Not only is the I-60 less expensive to install and maintain the first year, but it also does not have any overhead costs attached to it in subsequent years. To install the I-60 rotors into the existing system, the initial costs are approximately $2,638, after which there are no more costs. The pump installation option costs are approximately $3,664 for the first year (separated as $2,787 for initial installation and $877 for yearly recurring costs). In the first year alone, the pump option will cost $1,026 more than just installing the I-60 rotors. Also, the costs of a booster pump in the system after the first year will be approximately $877.
| Irrigation Specifications: |
| Original System Operating Zone Pressure |
70 psi |
| New System Operating Zone Pressure |
40 psi |
| Original Rotor Spacing |
62' |
| Original Nozzle Size |
20 gpm |
| Total Rotors in Park |
30 |
| 100 gpm Zones |
6 |
| Option 1: Booster Pump |
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| Estimated Cost of Pump Installation |
$2,787 |
| Yearly Electrical Energy Cost |
$337 |
| Yearly Pump Maintenance Labor Overhead Cost |
$540 |
| Initial Installation Cost and First Year Operating Costs |
$3,664 |
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(Cost comparison utilizes prices quoted to a specific city.
Actual costs may vary by region)
| Option 2: I-60 Rotors |
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| Estimated Cost of Rotor Installation |
$2,638 |
| Yearly Electrical Energy Cost |
$0 |
| Yearly Rotor Maintenance Labor Overhead Cost |
$540 |
| Initial Installation Cost and First Year Operating Costs |
$2,638 |
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New Design and Installation
 New 10 Acre City Park, Specified 100% Hunter Product
SITUATION: A city has decided to specify the installation of 100% Hunter product in a new park. The park has 76 psi available static water pressure and two 2" water meters under which the system must be designed. Now, the only question is what type of rotor does it make more sense to install. Under consideration are the I-25 and I-60 rotors. The I-25 rotors must be spaced closer together, requiring more heads per acre. Choosing the I-60 not only means fewer heads covering a greater distance, but also heads that can deliver water more efficiently at the site’s lower pressure.
CONCLUSION: The cost of Hunter irrigation products needed for this 10-acre park is approximately the same, whether the I-25 or the I-60 option is installed. The difference is only slight, with the I-60 system coming in just $161 less. Where the real money is saved is in the piping material and the labor to install the complete system. A very rough comparison estimate ratio that is intended to show the amount of material needed for the two systems indicates that the I-25 system will use at least 23% more pipe and fittings than the I-60 system. This ratio is directly linked to material costs. The biggest cost savings show up in the installation costs, with the number of rotors needed (and, therefore, the accompanying cost of labor) being over 62% higher installing the I-25 system as opposed to the I-60 system.
| Specifications |
Option 1: I-60 Rotors |
Option 2: I-25 Rotors |
| Available Static Pressure |
76 psi |
76 psi |
| Dynamic Pressure Losses |
-36 psi |
-36 psi |
Operating Rotor Pressure
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40 psi |
40 psi |
Nozzle
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12.5 gpm |
6.6 gpm |
| Spacing |
58' Equilateral Triangle |
58' Equilateral Triangle |
Rotors per Acre
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16 |
26 |
Total Rotors
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160 |
260 |
Zones
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20 |
18 |
| Pipe Between Heads |
9,280' |
11,440' |
Prices shown are suggested list and do not include
local discounts or incentives.
| Hunter Product Price List |
| Option 1: I-60 Rotor System |
Option 2: I-25 Rotor System |
| (20) ICV-210G 2" Valve |
$2,540 |
(18) ICV-201G Valve |
$2,286 |
| (160) I-60 Rotors |
$14,392 |
(260) I-25 Rotors |
$14,807 |
| (1) ICC-1600M Controller |
$697 |
(1) ICC-1600M Controller |
$697 |
| Total Cost |
$17,629 |
Total Cost |
$17,790 |
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I-60 is the One!
 As both examples demonstrate, the I-60 rotor not only delivers high performance, but it does so in an economical manner that other rotors are hard pressed to match. Whether you are dealing with a retrofit or a new installation, if you have a landscape that encompasses a large expanse of turf and you are dealing with low operating pressures, no rotor offers a better solution than the I-60.
Material Cost Ratio Estimate:
The I-25 system will require 23.2% more material.
Compare the amount of pipe used for the I-25 system vs. the I-60 system (11,440'/9,280' = 1.232).
Labor Cost Ratio Estimate:
The I-25 system will require 62.5% more installation labor hours.
Compare the number of rotors needed for the I-25 system vs. the I-60 system (260/160 = 1.625).
Calculations
Example 1 – Retrofit/Option 2
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Estimated Wholesale Cost of Rotor Installation
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| (30) I-60 Rotors: |
$1,888 |
| Labor Cost ($25 per Rotor) |
$750 |
| Total Cost |
$2,638 |
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