Little Bennett Pump Station Upgrade

Did you have any idea an irrigation pumping system was so complex?  

Little Bennett has just upgraded from an antiquated, energy-wasting system to a new state of the art control system that will provide dramatically improved and safer performance, use less electricity, and give the superintendent the ability to see what is happening at the pump station from anywhere there is internet access!

Golfers may occasionally wonder what it takes to irrigate a golf course.  An 18-hole golf course can cover anywhere from 100-300 acres of land and requires miles and miles of pipe to deliver water.  At least 2 to 4 pumps are required to keep pressure and move water across the golf course.  These pumps can provide up to 2500 gallons per minute(GPM).  Main pumps are powered by 50-75 hp motors and most courses utilize a small pump called either a jockey or pressure maintenance pump.  These smaller pumps are powered by 5-25 hp motors.  The small pumps are there to maintain pressure on the irrigation lines and for low flow operations.  An example of low flow would be 1 or 2 irrigation heads running or multiple hoses being used.  Pump station output is usually 10 times the horsepower of all your motors combined in GPM. 

Little Bennett runs two 75hp main pumps and one 25hp jockey pump.  The pumps are 20 feet long and are located in a wet well inside the pump house.  The pumps draw water for the golf course from the irrigation pond on hole #10.  The station requires 460 volt 3-phase incoming power.  The system was designed with a pressure tank and regulating valve to deliver 1800 GPM at 125 psi.  There's a panel that controls motor/pump starts and stops and is run by a programmable logic controller(PLC).  The PLC controls the station by inputs that regulate when pumps turn on and off based on pressure and flow.  The tank is designed to build pressure on the upstream(between the pumps and the valve) side.  When pressure drops on the downstream(between the valve and outflow pipe to the golf course) side of the regulating valve(e.g., heads running on the golf course), the valve opens and allows pressure to equalize.  When pressure in the tank becomes equal to outflow pressure the valve opens completely and allows water to flow freely.  The PLC calls for a pump to turn on and it comes on at full speed for however long it takes to build pressure back up and sustain flow.  This is what is called a fixed-speed system and this is very energy inefficient. 

old pump station control cabinet with PLC

old pressure tank

We decided that it was time to upgrade our control capability and take advantage of new technology.  The jockey pump and regulating valve were worn out and not functioning well and there was concern of interior deterioration of the pressure tank.  We've had to adjust our effective output down to 1000 GPM to prevent the system from shutting down.  The pump station was faulting more often than it would run successfully due to high and low pressure situations and component failure inside the cabinet.  The control cabinet was also becoming obsolete and components were either very expensive or impossible to find. 

The best time of year to do any work to a pump station is late fall/early winter when the need for irrigation is minimal.  We knew that we would have no capability to pump water for at least 7 days once work was started.  Contractors were selected for this specialized work and work began the week after Thanksgiving.

The work to be done included demolishing the cabinet, valve, and tank.  It also included removing and replacing the jockey pump and motor.  A new control cabinet would be put in place and a new manifold and section of pipe would replace the tank and valve.  The new cabinet would contain two variable frequency drives(VFD) that control the motors and pumps.  The VFD regulates the amount of power supplied to the motor and only allows the pumps to turn at the speed required to deliver the amount of water that is needed.  This is very energy efficient.  Radio receivers would be installed at the pump house and maintenance shop so that we could view real time pump performance.  This would also allow the greens staff to view the pump station PLC screen at any time and from anywhere using remote log-in to the irrigation computer.  In the future the radio communication will allow us to integrate the pump with the irrigation control computer for truly optimized pump performance.

Here are the main project phases in pictures:

Demolition of the old tank

Demolition of valve and control cabinet

Ready for manifold

New manifold going in

Manifold attached and skid primed

Carefully moving the new control cabinet in the door

New cabinet in place on the skid

Crane setting up to remove old jockey pump and motor

Pump coming out through opening in the roof

New pump going in

New pump installed and skid freshly painted

new, state-of-the-art, control cabinet PLC interface

Installation of radio receiver at maintenance building

With the work now completed, we expect to have a much more efficient pumping system.  We should realize a significant reduction in energy usage and associated cost.  Since we have a better functioning station, we should be able to effectively run at a higher GPM than in the past.  This will shorten the amount of time that it takes to run irrigation programs.  High and low pressure faults will mostly be eliminated with the new control system.  Dangerous pressure swings will also be eliminated and that should lower the number of pipe breaks we face every year.  This is a crucial infrastructure upgrade that benefits the golf course but is not something our golfers would normally see!

Matt Burton

Golf Course Superintendent

Little Bennett Golf Course

Needwood bunker rebuilds

About 3 weeks ago now, Needwood broke ground on some important bunker renovations.  This work will continue as weather allows into late fall and early winter, with the goal of finishing rebuilds of the remaining bunkers on the front 9.  There are 12 bunkers left to rebuild on the main course; others have been completed (or eliminated) over the last couple of winters.

It's ironic how bunkers are a hazard, but there is an expectation for them to be well groomed, well drained, trimmed and proper.  Don't worry, if you fall into this category, you're not alone; this is something that permeates the golf industry, and probably is mostly due to conditioning of golf courses shown on TV for tournaments, where they have many dozens or sometimes hundreds of volunteers to help make things, like the hazards, perfect! 

Much data has been comprised regarding bunker maintenance, and believe it or not, there are courses out there where bunkers require as much as 50% of the entire golf course labor budget!! 

About 4 man-hours of work will get just this one small bunker playable again after being washed out by a storm. Silt has to be manually removed by shovel, new sand added, and all the sand has to be redistributed by machine and finished by hand.  This example is from Falls Road, where there are 59 bunkers.  Repeat the process every time there is a major rain event!!  And yes, this is a HAZARD.  :-)

A large portion of maintenance labor is expended while trying to put bunkers back together after a major storm.  For us, while precipitation amount trends are only very modestly increasing on an annual basis, the frequency of rain days seems to be changing, especially in the summer, where we get most of our monthly rainfall amount from 1 or 2 storms.  What does this mean for bunkers?  More washouts and vastly more intensive work to make them clean and playable again! 

While not all bunkers a ruined to the same degree as in the above picture, there is plenty of work to be done.  The above bunker was not originally constructed with a liner, which would help the water flow underneath the sand to the drain and reduce washouts.   Installing proper drainage lines and installing a roughly 1/2" thick synthetic fabric liner especially on sloped areas, is what we are undertaking at Needwood, along with adding new sand.

Similar projects are occuring at every course in our system over time, and most every off-season as necessary.  This periodic maintenance allows us to be more efficient with our resources and focus on turf-related playing conditions!

Below are some pictures of the process going on at Needwood!

Old bunker sand is pushed into a pile and then buried into a hole inside the bunker.  The excavated soil is essentially "swapped" to the surface and used for creating the new floor of the bunkers.  This eliminates having to haul as much as 20 - 30 tons of sand out of the bunker across the course, and speeds the process.

After the new bottom of the bunker is installed, drain lines are trenched.  One of the big issues with these bunkers at Needwood is that they either completely lacked drainage, or the drainage had failed over time.

With drain lines complete, this bunker is ready for pipe, gravel and liner installation.

Outlet drains are also trenched.

Pipe is installed and trenches are backfilled with pea gravel.

Ready for liner!

Liner is carefully installed in the bunker, using a LOT of sod staples (about one per foot).

Once sod staples are in place, each one gets some Liquid Nails to help hold them in place.  Without this, freeze/thaw and natural minor heaving can allow the staples to work themselves loose.

As liner is installed, thin pieces of plywood also help maintain a proper edge when adding sand later.

Final touches need to be made outside the bunker where some bunker edges are modified.  These spots will be sodded and re-established quickly.

Once the liner is trimmed up, sand is added and distributed throughout the bunker, generally to a 6" depth on bottom and a 4" depth on the sloped areas (less sand makes bunker faces a little firmer to prevent fried-egg lies)

Forward tee construction at Northwest

If you have played Northwest from the forward tees, then you know that some of the teeing areas are not level.  Since this golf course was not originally constructed with forward tees in mind, an area of rough mowed down to tee height and converted to perennial ryegrass has been the norm. .

Superintendent Chris Fernandes and his team have begun taking the most out-of-level teeing areas and building a proper tee box on holes 6, 9, and 18 so far.  And apparently it has been well received, indicated by the hugs he has received from some of our lady golfers there, who are thrilled at the new addition of these tees!

New tees were built closer to cart paths for easier accessibility and reduced turf wear.  Each area was built up with some good local topsoil, and graded to a fine level with hand rakes while using surveying equipment to ensure they are precisely correct.

Sod was stripped off the old tee box and transplanted to the new one, and the new tee boxes were well-rooted and ready for play in as little as one week!

Kudos to those guys for a great job, and some much appreciated work!

stripping sod off new tee location

staking out area to be levelled

a little hand raking after rough grade established

plate tamping the surface

Rough sod outlines the tee box; ready to be grassed!

New tee box ready to go!  This tee box was opened for play in 14 days after some quick rooting of the ryegrass and tall fescue sod.