There are a lot of options to consider when selecting a gutter system for a swimming pool.
The primary purpose of a swimming pool gutter is to skim debris from the water surface. The operating water level is set slightly above the gutter lip such that water around the full perimeter of the pool continually flows into the gutter trough.
Additionally, the gutter trough must be able to capture waves moving across the surface of the pool.
Because a gutter has the ability to capture waves (whereas a skimmer-type pool does not) it is the preferred overflow system for competition pools, and is often preferred for recreational pools as well.
The gutter trough must be designed such that it does not flood during high wake situations, such as when the pool is full of swimmers on a sunny summer day, or during a warmup session for a swim meet. This is done by considering both the depth of the gutter trough as well as the size of the pipes which drain the gutters back to the surge tank.
The most debated aspect of swimming pool gutter design is the gutter configuration. There are many pros and cons for each gutter type, and many opinions on the this topic among swimmers, coaches, swimming pool designers, swimming pool operators, and others.
The four basic gutter types we will look at below are fully recessed, rollout, rollout with parapet, and deck level.
Fully Recessed Gutters
The fully recessed gutter features a concrete cap which is cantilevered over the gutter grating, creating a 12” deck-to-water dimension. This gutter type has two main purposes.
First, this type of gutter provides a visual reference for the end wall above the water surface. As swimming techniques improved over the years, competitive swimmers are now taught to maintain a streamline position throughout their strokes. This means that swimmers are looking at the pool floor markings and not at the end wall, making the need for an above-water reference point less important than in days past.
Second, the recessed nature of this gutter helps keep the wake from splashing out of the pool, which is always desirable.
The fully recessed gutter makes egress from the pool quite difficult without the use of grab rails or a stair entry. Even some high school and college swimmers will have difficulty climbing out of the pool with this gutter type.
During swim practice, when swimmers are at the end of the pool receiving instructions from their coach the cantilever cap provides an echo chamber near the swimmers ears which can make it difficult to hear.
The raised gutter face at the end of the pool is necessary when a pool is intended to host international / FINA sanctioned swimming competitions due to the specific requirements for the height of the touch pads above the water surface. Swimming competitions sanctioned by USA Swimming, NCAA, or NFSH, require only gutter-hung touch pads which do not need to extend above the water surface.
Fully Recessed Gutter
The rollout gutter does not have a cantilever top over the gutter grating. A 5” curb is provided at the rear of the grating to help minimize splash-out. This curb also provides a visual reference above the water surface, however this reference is not in the same plane as the end wall.
In contrast with the fully recessed gutter, the rollout gutter provides easy egress for most swimmers because the gutter lip and grating is at the same level as the water surface.
The absence of the cantilever at the end of the pool eliminates the echo chamber effect.
Rollout Gutter with Parapet
The rollout gutter with parapet is similar to the fully recessed gutter in that the ends of the pool have a 12” deck-to-water dimension. This is accomplished by creating a raised parapet at both ends of the pool. The sides of the pool feature a rollout gutter style, which is able to interface nicely with the end-wall parapets. The parapet provides the same visual reference above the water surface as the fully recessed gutter and allows the installation of touch pads meeting the requirements of FINA for international competition.
Similar to the fully recessed gutter, it is difficult for most swimmers to exit at the pool at the parapet. The rollout gutter along the sides of the pool does allow for easier egress at times when the pool is not being used for competition.
Another disadvantage this gutter configuration shares with the fully recessed gutter is the echo chamber created by the cantilever gutter cap.
Rollout Gutter with Parapet
Deck Level Gutter
Speaking not only as a swimming pool designer, but also as a swimmer and a coach, the deck level gutter configuration is usually the best choice. The deck level gutter has minimal separation between the water surface and the pool deck. Depending on the selection of gutter materials, tile trim, etc. the deck-to-water dimensions vary between one inch and zero inches. With the water surface and the pool deck aligned on the same plane, an attractive look is created. Egress from the pool is the easiest with this gutter type and able to be performed by most swimmers without the assistance of a ladder or stair entry.
Parallel grating is a must with this gutter type to minimize splash-out. Grating oriented perpendicular to the pool wall allows water to ride across the grate and onto the pool deck. Parallel gutter grating, with the proper amount of open area, captures the majority of waves created by swimmers – including during the start of a race or when swimmers perform flip turns. The deck level gutter also encourages better swimming technique as swimmers are more inclined to keep their eyes on the floor markings, rather than looking above the water surface for the pool wall.
Similar to the rollout gutter, the echo chamber effect is avoided with this gutter type.
The deck level gutter is not without disadvantages. With this gutter type, the lane rope cup anchors are set several inches below the water level, causing the lane ropes to submerge slightly for a few feet at each end of the pool. With the lane ropes submerged they are not very effective at quelling waves in this zone. The actual impact this causes on competitive swimmers’ times is negligible, but nonetheless some will question this aspect of the design.
Another disadvantage is the height of the starting block platforms above the pool deck. Starting blocks are typically designed for the maximum allowable height of 29 ½ inches above the water surface at the leading edge of the platform. Because there is no difference between the water and deck elevations the full 29 ½ inches must be achieved above the pool deck. With the other gutter choices, the height above the pool deck can be lower because a portion of the starting block height is provided by the deck-to-water differential. Only experienced swimmers should use starting blocks under the supervision of a coach.
Deck Level Gutter
There are many options when it comes to selecting a gutter configuration for your new swimming pool. Each type of gutter has several advantages and disadvantages. It is important to consider all of the pros and cons and their impacts on all of the potential user groups before choosing the configuration of your gutter system.