SCBID TRAVELING WEED SCREEN PROGRAM...A look at the weed problem – Primarily in the context of...
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SCBID TRAVELING WEED SCREEN PROGRAM Eric Dixon, P.E. Chief Engineer South Columbia Basin Irrigation District
Transcript of SCBID TRAVELING WEED SCREEN PROGRAM...A look at the weed problem – Primarily in the context of...
SCBID TRAVELING WEED SCREEN PROGRAMEric Dixon, P.E.Chief EngineerSouth Columbia Basin Irrigation District
OVERVIEW
A look at the weed problem– Primarily in the context of pumping plants
Some common approaches to handling weeds/debris
SCBID traveling weed screen programResults
**Primary focus is on techniques/methods used by SCBID
THE PROBLEM…
Weeds, more weeds, and some other stuff– Weeds: aquatic, terrestrial– Other stuff: crops, garbage, general debris
THE PROBLEM CONT.
THE PROBLEM CONT.
Sometimes the Debris is really big!!
Public Safety Announcement: Don’t text will tractoring…
THE PROBLEM CONT.
So what happens???– Intake racks blocked – pumps shut down
• Service interruptions• Canal/Ditch fluctuations upstream and downstream• Racks must be cleaned & pumps restarted
SCREENING/HANDLING
Two approaches (not going to talk about weed treatment/prevention programs)– Manual Labor– Mechanical
SCREENING/HANDLING CONT.
Manual Labor– Use of rakes/hand tools by employees– Labor intensive/time consuming– After hours call-outs and overtime– Safety hazards
• Night work near water• Physical strain
SCREENING/HANDLING CONT.
Mechanical– Various methods
• Automated rakers (various types)• Rotating drum screens• Passive screens• Traveling screens• Use of heavy equipment: excavators, etc.
– All three Districts in CBP using some or all of these mechanical methods.
SCREENING/HANDLING CONT.
Mechanical– Automated Raker
SCREENING/HANDLING CONT.
Traveling Screens– Simple design
concept– Typical installations
• Move material in a downstream direction
• Require structural work in channel
• Require space downstream for material deposit
SCREENING/HANDLING CONT.
Traveling Screens Cont.
SCBID TRAVELING SCREEN PROGRAM
We are a little backwards down South– Standard traveling screen concept but run
them against the flow
SCBID TRAVELING SCREEN PROGRAM
Why???– No structural work required in the channel
with one exception– Minimal modifications required to pumping
plant structure– Material is deposited upstream away from the
pumping plant for better access/cleanliness– Some redundancy is maintained with
remaining bar racks
SCBID TRAVELING SCREEN PROGRAM
The Prototype– Constructed in-house winter 2015– 28 CFS (12,600 GPM) pumping plant
SCBID TRAVELING SCREEN PROGRAM The Basics
– Box sits on P.P. apron – screen sits on box– Existing bar rack removed at box outlet– Flow over screen through box
SCBID TRAVELING SCREEN PROGRAM The Basics Cont.
– Epoxy coated frame and box– Polymer screen material– No moving parts under water– Small ½ HP drive motor with timer/manual
control
SCBID TRAVELING SCREEN PROGRAM
Results– Very quick in-field installation time– Extremely reliable– Little to no maintenance– No fouling of polymer screen material
• Spray bars not required– No pumping plant failures due to
weeds/debris
SCBID TRAVELING SCREEN PROGRAM
Results Cont.– Example: 2019
Installation• EB1 PP: 75 CFS
(33,700 GPM)• Typically offline
20-25 times due to weeds/debris
• This year no plant failures due to weeds/debris
CONCLUSION
SCBID on 5th year of program– Exceeded expectations– In-house construction allows us to: control costs,
implement unique configurationsWeed/debris handling remains a continual
problem for all CBP Districts.Various Methods, One Goal:
– Deliver water to our landowners• Safely• Reliably • Efficiently
ANY QUESTIONS?
Eric Dixon, P.E.Chief EngineerSouth Columbia Basin Irrigation District
