Report: Addition of Rain Bird PRS
Date published: May, 2013
Measure the water consumption and efficiency of an existing rotor system before and after the addition of Rain Bird Pressure Regulating Stems (PRS).
- The test zone for this audit was a southward-facing slope with established drought-tolerant trees, shrubs and groundcovers.
- After a control test, the shrub risers were fitted with Rain Bird PRS devices spaced approximately 40 feet apart at the top of the slope, using the same heads and nozzles.
- System efficiency was evaluated using two standard irrigation measurement methods: Distribution Uniformity (DU) and Scheduling Coefficient (SC). High DU readings reflect more even coverage of a zone. A lower Scheduling Coefficient means a shorter run time was necessary to water a zone properly.
The pre-audit segment of the test was performed on the existing irrigation system components without the PRS and resulted in the following system observations:
|System Efficiency (DU)||43%|
|Flow rate||29.6 gpm|
|Volume of water used for test||553 gallons|
Following the pre-audit the shrub risers were fitted with the Rain Bird PRS devise using the same heads and nozzles as the control test of the pre-audit. The results were:
|Post-Audit||Test #1||Test #2|
|System Efficiency (DU)||55%||58%|
|Flow rate||27.4 gpm||27.4 gpm|
|Volume of water used for test||512 gallons||513 gallons|
|Audit Performance Summary
||Test #1||Test #2|
|System Efficiency (DU)||13% (better)||15% (better)|
|Scheduling Coefficient||82% (better)||82% (better)|
|Flow rate||7.4% (better)||7.4% (better)|
|Volume of water used for test||7.2% (better)||7.2% (better)|
After adding PRS to existing rotor system:
- Distribution Uniformity (DU) increased.
- Scheduling Coefficient (SC) was lowered.
- Water consumption was reduced.