Just as fields for various sports have different size and marking requirements, they have different slope and crown requirements. A qualified field contractor will know the cor- rect figures for each sport and, since toler- ances are very exact, will probably use laser-guided equipment to achieve them. "The key to good drainage is moving water the shortest distance possible in order to get it off the field," says Wright. "For ex- ample, in a baseball field, you wouldn't want it to drain from home plate to the outfield." The high point of a baseball or softball field generally would be the pitcher's mound, which is 10" above home plate. The field is then sloped in all four directions away from the mound and across the skinned areas. Rectangular sports fields, those used for
sports such as soccer, field hockey, lacrosse and more, also have specific slope require- ments and generally include a crown running down the center of the field so that water drains in two different directions, toward some type of collector drain system described above. (An exception to this rule would be a grass tennis court, which while it is a rectan- gle, must drain in one true plane). Different governing bodies, such as the NCAA or the NFHS, will require varying degrees of slope for each sport. Ascertain you are working with the most current version of the rules for the correct governing body prior to embark- ing on any grading work. Assuming your facility design now en-
sures that all the water now falling on your field is from precipitation or irrigation, and assuming your field design includes correct slope, you can concentrate on some of the additional mechanisms used to help natural fields drain properly. A subsurface drainage system (so called because it manages water that makes its way underground) can help fields dry more quickly, avoiding rainouts, unsafe conditions for athletes, and the chance of the turf being torn up while a game is in progress. Unfor- tunately, extra drainage, because it is invisi- ble to the naked eye (unlike, say, a new scoreboard or a press box) is where field owners sometimes skimp, trying to save money. However, experts agree that both the usefulness of the field and its long-term per- formance, are tied to having an effective drainage system.
www.stma.org SportsTurf 31
