Bunker Renovation Update

Metamora Golf and Country Club  is going to perform a two phase bunker renovation project starting this April; we hope to have this first phase completed in May. The reason for the two phases: a complete renovation can take a while to complete, especially when doing it ourselves and not contracting the work out. We want to make the bunkers better now, yet give us the time to complete phase two later. Right now, our bunkers need this "quick fix." The first phase will consist of removing all the current sand and contaminates from the bunkers, and repairing any poor drainage. After this process is complete, new sand will be added to all the bunkers. Below are some pictures of bad drainage that must be repaired during this phase. When this phase is complete, the bunkers will perform very well, and it will give us the much needed time to complete phase 2.

The second phase will begin at a later date, and it will consist of a complete renovation which will require a lot more time and attention to individual bunkers. This phase will include some minor reshaping, a better drainage system, and a sod lining system which will reduce sand contamination during rain events. This type of renovation was performed on the green side bunkers of holes #1 and #4. This phase is explained in greater detail in the bunkers label.

Metamora's bunker renovation step by step.

I mentioned in the previous post what the bunker renovation process entails. In this post I will explain in greater detail the entire process. Below is a step by step list of what goes into Metamora's bunker renovation with pictures for you to enjoy.

The first step is to remove the old sand and few feet of turf that surrounds the bunker. The turf removed from the perimeter helps us define the size and shape of the bunkers. As bunkers age they typically get smaller, in our case some of the bunkers are close to 25 years old.

Old sand and grass being removed

 Sand piled up for removal

The next step is to remove the old drain tile and bedding material like pea stone or gravel. Once that is completed, the bunker floor is re-graded.

Old drain system being removed

The bunker floor being re-graded

During the re-grading process sometimes you find surprises.

A huge rock right under the surface

The third step is creating the new shape and style. As mentioned bunkers shrink over time due to sand build up. When smaller bunkers are preferred, but there is a sand build up that you don't want to or can't remove, burlap bags filled with topsoil make a great alternative. These bags can be stacked and molded. Using sand as a wall is not a good choice as it doesn't create a firm foundation to keep sand inside the bunker and doesn't hold up well to traffic from golfers and especially mowing equipment.

Sand build up in front of bunker

Burlap bags filled with screened topsoil

Once the bunker floor is graded, new drain lines are dug. Every bunker may have different drainage patterns. This depends on the size and shape of the bunker. In many cases new exit drain lines have to be installed. This is due to the new drainage system being installed much deeper than the original system.

New drain line trenches

Drain line trenches

Once the dirt from the drainage trenches is raked out or picked up, instillation of the new drainage system is installed. The new system, I am very excited about. This drain tile is spiral corrugated inside and out, fitting screw on and this pipe is bedded in sand. This system has been very easy to install and given how much rain we have received so far this fall it is working great.

ADS Turf flow fine perforated drain tile

Drain tile getting back filled with sand

Closer look at tile being bedded in sand

After the drain system is installed and trenches are back filled with sand to the bunker floor, we begin laying down sod. The sod inside the bunker is being used as a liner. This grass will be killed with round-up and new bunker sand will be installed on top of it. The sod's organic matter or thatch is what is used inside the bunker. The thatch which is composed of cellulose and lignin becomes a barrier between the native soil and the new bunker sand. The cellulose portion of thatch will decompose where the lignin portion will stay around for a long time. I have talked with several people that have used this method and they all feel it has worked well for them.




Finished bunker with drain lines exposed

Finished bunker

The last step in the renovation process is obviously the addition of the bunker sand.

The Bunker Renovation

Our bunker renovation has started and we are all excited to see this happening. Renovating bunkers is a lot of work, but well worth the effort.

I get asked a lot of questions regarding our bunkers. Here are some answers to some of the questions.

Why don't you just add more sand? The current sand is contaminated with silt and gravel. Silt is the biggest reason the bunkers don't drain well. Adding new sand wouldn't do a lot in this case because proper drainage is our biggest concern.

Can you just take the old sand out and put in new? Unfortunately the silt has worked its way down to the drain tile and has clogged up the perforations in the tile. In some cases socked drain tile was used and the sock is clogged up with silt. The existing tile was also shallow has been nicked with the bunker machine and silted sand has entered the tile.

What does the bunker renovation entail? Our bunkers are getting completely overhauled. As mentioned before the old sand is removed. We also strip about 3-4 feet of grass around the bunker, this helps define the original size and shape. This grass will be discarded because it's inconsistent and replaced with new sod. The old drainage system is removed and also discarded. After altering the shape, the sub floor is re-worked to create a floor that is flat, free of rocks and slopes slightly to future drain lines. The next step and the most important step is a new drainage system is installed. Adequate drainage on the entire golf course is important, but in bunkers it's critical. As we replace the grass that was removed around the edge with sod, we will also be lining the entire bunker with sod. I have talked with several people that have done this and it's inexpensive and very effective.

The New Drainage system
The new drainage system is unique, the pipe size is smaller than the old system but more drain tile is added. There are several things I like about this drain tile. The holes are a lot smaller than the old conventional drain tile. Unlike the old perforated tile that was back filled with pea stone, this particular tile is actually back filled with sand and is installed deeper than the old system. I really like this because it eliminates the risk of pea stone contaminating the sand. Another benefit of this type of system is the sand can easily be removed and replaced if needed and the tile itself is much easier to work on. The new drain tile has spiral corrugations inside and out and fittings screw on snug to keep sand out. Also with a spiral interior water flows through it faster which is very important in bunker drainage.

The video link below will help explain why a bunker renovation is necessary

USGA Bunker Video

Bunker edging and another small project

All of the bunkers have been edged and are looking good.  The next area we are going clean up is the parking lot by #6 Tee.  This area collects a lot of leaves and other debris because of how wet it seems to be all the time.  Our plan is to remove some of the dirt and add smaller stone.  This should help keep this area dry at the surface and will add a nice touch.