Puddles and Birdbaths




A birdbath is any area that holds surface water of a thickness greater than a nickel, after the source of that water has been stopped for two hours. The puddle may take many shapes and run in many directions. Usually a puddle accumulates along the asphalt seams or edges of the tennis court.

NOTE: Although puddles are undesirable, they are common and usually a result of the minimal pitch applied to a tennis court surface. It would be easy to eliminate all puddling, if upon construction, a pitch of 1″ every 6′ or 7′ were integrated into the court surface. However, this pitch would make the court surface almost unplayable as the court would be tilted so severely that the players would feel like they were playing on a hill. For this reason puddling on a tennis court is very common.


All hard surface tennis courts are constructed with a pitch or fall to allow the water to run off the court. Generally this pitch is a 1″ drop for every 10′ of surface, usually from side to side, but in some cases it may be end to end or from the net to each end.

When the asphalt or concrete is initially laid, this pitch is incorporated into the base preparation. If at any time during this construction, the ground is not properly compacted or evenly graded, the result will be birdbaths or puddles. The severity of these puddles will depend upon the degree by which the grade or compaction was not properly designed or constructed. The possibilities of repair will also depend on the design and construction mistakes.


Sinking is a result of improper compaction of the sub-base (natural dirt) prior to laying the base (asphalt or concrete). A minimum compaction of 97% must be established consistently over the entire court area to avoid puddles caused by settling. Also, all organic materials such as tree- stumps, roots, grasses, lumber and garbage must be removed from the sub-base prior to compaction and construction. All of these materials will eventually decompose, settle and shrink, causing the materials above these decomposing items also to settle which will result in a surface puddle.

A core boring of the area must be made to establish how large the underlying problem is. Many times a small 1′ diameter puddle will be sitting on top of a 30′ x 40′ construction dump site. After the borings are taken, a decision can be made to excavate the site or simply fill the existing puddle with asphalt or acrylic filler material. If the puddle is caused by settling or decomposition, there is no solution to the problem until the entire area has stopped settling or the area is excavated, filled and compacted.

Water Puddle Caused by Sunken Area

B. UNEVEN ASPHALT OR CONCRETE: Unevenness caused by improper rolling of the asphalt or the screeding of the concrete. Generally what happens is that the direction of fall is interrupted by a high area in the surface. This high area acts as a dam, stopping the water and causing a puddle.

SOLUTION: One of two things may be done in this case. First, the high area may be ground down to allow the water to continue its flow, or second, the low area may be built up enough to re-establish the necessary grade.

In the first instance, the degree of material that may be removed depends entirely on the thickness of the asphalt or concrete. Under no circumstances do you want less than one inch of asphalt or less than 3″ of concrete, so if your asphalt or concrete are already at these minimums, you obviously cannot use this solution.

The cure for the second instance of puddling depends on the height of the dam. If the ridge is more than 1/2″ above the area from which the water is flowing, then realistically you will not be able to completely remove the puddle. You should, however, be able to reduce it by some amount less than 1/2″.

Many times in dealing with puddles, reduction, not elimination is the only possible goal. If you try and lift an area too much you simply instigate another damming effect but to a different area. This is referred to as “moving a puddle”. Sometimes this will be done to get a puddle out of the play area and into an area outside the playing lines.

This is generally caused by the accumulation of vegetation or dirt along the low side of a tennis court. These items build up a dam or wall by which the water cannot penetrate or pass, thus holding the water on the side of the court. Sometimes these areas can build up so high that the water will encroach back into the court area 25′ to 30′.

SOLUTION: Remove the debris and trench, around and down the low side of the tennis court. If this problem is caused by roots or plants, they must by removed or at least cut back. Landscaping around a tennis court adds to the beauty of the court but unless carefully planned, it can cause expensive damage to the court surface and in some cases require the removal and re-laying of the base material.

Water Puddle Caused by Raised Asphalt


Generally birdbaths and puddles are nuisances, not problems. In some cases, however, a puddle can turn into a very dangerous slick spot on a tennis court. If water sits in an area for a long period of time, algae will grow on the court surface. Algae can be as slippery as ice causing players to slip and fall, resulting in injuries and possible lawsuits. At the least, the court surface should be pressure washed twice a year if low areas are causing these slippery spots. Although the pressure washing will not correct the problem it will keep the court surface from becoming a hazard and help to keep the surface from suffering unnecessary wear.

Gary D. Whalen and The Whalen Company have built tennis courts for 40 years in Florida, Georgia, North Carolina, South Carolina, Tennessee, New York, Ohio, Alabama, Connecticut, West Virginia, Virginia, Dominican Republic and Maryland.