Surmount bridge-construction obstacles
Wetlands mitigation, construction restrictions and land use contribute on a daily basis to the need for more and more bridges to be built on our nation's golf courses. Golf-course superintendents find themselves in the role of contractor in these situations, and--in many cases--must analyze the need for bridges and solicit bids for this highly specialized work. Finally, the superintendent must often choose and work with a bridge company.
Here, we'll familiarize you with the basics of determining actual bridge needs pertaining to timber bridges--one of the most popular type of bridges used on golf courses. We'll also discuss the factors to consider when choosing a bridge company and what to expect from both the bridge company during construction and the final bridge itself. The primary thing to remember is that the process is not as easy as simply purchasing a bridge. As a rule, it is a much more complex issue.
What do you need? First, determine your need. Obviously, you can decide that bridges are necessary for a variety of reasons. For example, you build bridges by necessity, such as when you need to re-route traffic because of drainage or play issues or because of wetlands concerns. Sometimes you must replace older bridges when they become a safety hazard or an eyesore. In other situations, you deal with land bridges, which might not have been regulated when originally constructed. Today, such bridges can inhibit water flow, and many superintendents find they must replace them with bridges that allow for proper water movement.
Such was the case at the Eagle Haven Golf Course on the Little Creek Naval Base in Virginia. Superintendent Mike Eller was faced with replacing three land bridges because of drainage and flooding issues. "One of the earthen causeways would flood if there was a heavy thunderstorm, causing me to shut down our entire back nine. Obviously this had to be corrected because of the loss of play and revenue that it caused," Eller says. Eller also noticed that some of the lakes on the course filled up faster than others. To make drainage more uniform and prevent flooding on one fairway, he decided to replace three earthen causeways with pile-supported timber bridges and make the three lakes one contiguous body of water. "That way," says Eller, " the lakes would accept the runoff equally and prevent overflow in any one lake." Aesthetically, the timber bridges were a definite improvement over the existing causeways, particularly the earthen causeway that he replaced with a timber, covered bridge. It added considerably to the beauty of the hole.
As mentioned, courses built 30 to 40 years ago suddenly face wetlands concerns because heavy rains "re-create" wetlands or because local environmental authorities realize a previously ignored or newly designated wetlands area may be in danger. Identifying a wetlands area is not always easy. Superintendents today regularly go through wetlands mitigation for bridge construction in areas that to the naked eye do not even resemble a marsh or wetlands habitat. Areas classified as wetlands often include swampy areas, streams, ponds and low-lying areas that only have standing water during heavy rains. The actual border of the wetlands area will often be wider than the physical or visual boundary of the stream or swamp, depending upon the soil and flora growing near the terrain feature. Inevitably, then, you need a bridge to preserve these natural habitats--particularly as environmental concerns take a more prominent role in golf-course construction and land use.
Eaglehaven's Eller faced these concerns early on. He found that the permitting process went through the Army Corps of Engineers. "The Army Corps of Engineers felt they had jurisdiction over the wetlands because the course was built through a swamp in the 1950s," Eller explains. To get the bridge work done, the Army Corps of Engineers asked Eller and his crews to relocate 640 square feet of wetlands flora. "I basically went to a local wetlands nursery and bought the plants I needed. We had to dredge along a lake-front area and plant these to keep the wetlands balance," Eller says.
Sometimes a course hires a superintendent before course construction is finished. In these cases, you can be involved in the bridge-solutions decision. Superintendent Darrell Dinkel, of River Valley Ranch Golf Course in Colorado, found himself in that position. Darrell became involved when course management was trying to determine what types of bridges to install. "The ownership decided a cost-effective solution would be to use timber bridges because course construction had reached the point where access was a problem and because timber matched the theme of the ranch development. And, there was no way we were going to get a crane in to put steel bridges across the river. That was where selecting a company that could build timber, free-span bridges on site came in," remembers Dinkel. "We had to still provide more access than I expected, but the crew was able to get the job done." Dinkel also faced wetlands concerns. "One bridge in particular used 100-foot glued, laminated wood beams (often called glu-lams) and getting them on site disturbed the wetlands area more than I expected. We learned on the first bridge so that when the next two were built, we made only a minimal impact on the surrounding wetlands area," Dinkel explains.
Other superintendents, such as Greg Nichol of Maplewood Country Club, Maplewood, N.J., are faced with replacing existing bridges that are no longer structurally sound. "We had some old steel spans with concrete footers that had to be torn out and replaced with new free-span bridges," Nichol says. "When we started our search for someone to build them, we found a company that was total turn-key and would come in and custom build what we needed, on site. That service and the informative literature and photos showing us exactly what they were capable of made the selection easy."
Nichols was sure his choice was right when his club got 8 inches of rain and exceeded the 100-year flood mark. "Some of our older bridges were destroyed by this raging water. One very solid stone wall was even pushed over. But the new bridges, after being pounded and submerged, were totally undamaged. Needless to say, we had that company come back to replace the remaining older bridges."
Structure and construction choices During renovation or new construction, some choose to build bridges to serve as part of a feature or signature hole and to help draw players. Others want a low-profile, aesthetic and functional bridge that will blend into the natural surroundings and not physically impede play.
Whatever the reason, determine your need and include factors such as the types of structures required and the types of construction permitted. These come into play early in the process. Bridge types range from pile-supported structures to free-span bridges that can span distances of up to 180 feet. Each has its merits and aesthetic qualities. Load requirements also play a vital role in selecting a bridge type. Determine the type of traffic that will use the bridge: Will it be for pedestrians only? Will it be for carts and light maintenance vehicles? Will heavier maintenance vehicles need to use it? The industry standard for cart bridges is 5 tons. This allows for light maintenance vehicles and is more durable even if used only by golf carts or pedestrians. In addition, 5-ton bridges are needed to build from the "top down" in areas such as lakes or areas where you are not allowed to use equipment on the wetlands floor.
Choosing which type of bridge to specify depends on your needs. To cross a stream, for example, the type of bridge and the type of construction you can use may depend upon a local-, state- or national-level regulating authority. Authorities in wetlands regulation vary from city to city and state to state and can include the Army Corps of Engineers, the Environmental Protection Agency or a local township body involved in permitting that type of work.
Once you identify the proper authority, contact them to find out exactly what guidelines you must follow to cross the intended area. Before beginning construction, ask certain questions. For example, can you penetrate the wetlands area, lake or stream bottom? If so, a pile-supported crossing is a good option. If not, the structure will need to freely span a designated area. Ask if equipment can enter the wetlands and to what extent. Depending on the type of area being crossed, bridge construction may be done from the floor of the wetlands. In other cases, authorities may allow the equipment in the wetlands but only in the "path" of the bridge. In still other cases, authorities will not allow equipment in the designated wetlands area at all. This means you must build the bridge "from the top down." In addition, authorities even may regulate the height of your bridge to clear what is known as the 100-year flood plain--a designated level where water could reach in extreme conditions.
Get an experienced bridge contractor involved at this point. That company will be able to provide further assistance and information on what type of structure will best suit the situation and what will be required to build it. Involve a bridge contractor early in the process to save time and money on the project overall and to prevent problems later. Legitimate bridge contractors provide valuable assistance in the form of site visits, conceptual drawings and useful information in the form of photographs, CAD drawings, specifications and budgetary numbers. Good bridge contractors also will work with you to help design a solution for whatever wetlands or terrain issues are involved. In most cases, this assistance is free, with the understanding that the bridge company will be able to bid on the project.
What is a bridge? Know what constitutes a bridge before going to bid or selecting a bridge company. The primary components of a bridge are the abutments, railing, piling, curbing, superstructure, covers, decking and coating. Each of these components is important to you as a superintendent. Consider each component carefully before choosing a bridge contractor or signing a contract.
Abutments. All bridges require abutments (see photos, above), which support the bridge at each of its ends. Along with abutments, abutment walls are constructed to hold the fill in place on either end of the bridge and serve to support the cart path leading to the bridge decking. Without proper bridge-abutment walls, fill can erode or slip from under the bridge end and cause cart paths to settle and crack apart near the bridge. On some bridge designs, the abutment walls help to support the bridge structure as well. Do not exclude abutment walls from a bridge design to save money. The costs to repair cart paths and refill the ends of a bridge will be significantly higher later on.
Railings. Three things determine handrail needs: the height of the bridge, safety and aesthetic requirements. If the bridge's height goes more than 2 to 3 feet above ground or water level, local safety regulations may require a handrail to prevent someone from falling off of the bridge. The actual regulations differ in each city, county and state, and it can be anywhere from 3 to 8 feet before a handrail is required. Safety concerns also can dictate how much of a gap is allowed in the actual handrail design. Some states require minimum gap sizes on bridges used by the public to prevent accidents involving children. Finally, you can include or exclude a handrail in the bridge design for aesthetic reasons. You must determine your specific need. (Do not attempt to add--or remove--a handrail on an existing bridge without consulting a professional bridge contractor. The handrail may be an integral part of a bridge's design or load-handling calculations.)
Piling. Common bridge supports are made of timber piling, with varying thickness depending on load requirements. The most common bridge type is pile-supported because of its ease of custom construction, variable weight-handling capabilities and relatively low expense compared to free-span bridges. These bridges are supported at intervals by timber piles that have been mechanically driven into the ground. Pile-supported bridges can be of any length, built to almost any height, and you can construct them from on top to insure minimal impact on the surrounding environment.
Curbing. Bridge curbing is built at or near deck level out of 4- x 6- or 6- x 6-inch lumber and serves to prevent carts from going over the edge of the bridge. The curb height depends on the need and typical traffic that will use the bridge. Timber curbs are standard on most timber bridges, and you can use them in the design to help change the appearance of the bridge.
Superstructure. The superstructure of the bridge includes the beams and stringers that support the deck and connect to the piling. Sizing of the superstructure materials depends on the capacity requirements. For example, many superintendents use bridges to carry irrigation piping across an existing body of water or wetlands area. Notify your bridge contractor early on if you plan to attach irrigation pipes to a bridge as they will play a role in determining the load-bearing design for the bridge superstructure.
Covers. Timber-covered bridges are a national icon. As an option for timber bridges, covers play two roles: aesthetic and functional. A covered bridge quickly becomes a course feature and is practical in that it also serves as a stopping area or rain shelter for golfers. With additional customization, you can add covered turnarounds, lookouts and rest areas to the bridge.
Decking. Determine what types of traffic will use the bridge. The deck-board thickness depends on the bridge's capacity. You should ensure the contractor nails down the decking using ring-shank nails to keep the deck boards from becoming loose and pulling out when the wood expands and contracts. Also, golf carts and maintenance vehicles will wear decking down. If it is in the bridge budget, consider adding wear deck to each bridge. Wear deck is an additional layer of deck boards, usually running perpendicular to the base-deck boards, that accepts the punishment of the elements and traffic, increasing the bridge-deck life span. You also need wear deck to prevent rapid deck deterioration by walkers with spiked shoes.
Coating. Where necessary, choose a non-slip wood treatment for bridge decks to prevent injury to walkers in spikeless shoes. Non-slip options include UV coatings with a gritty or metallic additive, rubber stripping and mats. However, mats are not typically advisable, as they will trap moisture underneath against the deck boards, which will speed up bridge deterioration.
Scheduling the construction Once you select a company, communicate your scheduling needs. Discuss the time frame the company needs to complete the project. In some cases, bridge construction may not affect play because you can set up alternate routes. However, if you will close part of the course or all of it during construction, consult with the bridge contractor on the length of time needed for the project's completion. Bridge contractors work shorter jobs, so scheduling is generally more difficult. Make sure the contractor gives an arrival date to within a few days. Supervise the project yourself, particularly if you close the course during the winter months or for renovation. Be available to answer questions from the crew on site or from the contractor's office.
Before the crew arrives, stake bridge centerlines and elevations and plan and stake access routes. Set specific access routes to the bridge sites and show them to the company representative before construction. This will be the route the construction crew will take with the heavy equipment to each bridge site. Keep this in mind and attempt to make the most direct route and avoid using areas around greens or across fairways unless it is absolutely necessary. The access routes must be wide enough for back hoes, front loaders or other heavy equipment. If you plan to use cart paths for equipment routing, be aware that the cart paths may not be designed for the weight of this type of machinery. The clearance width the route needs to be depends on the bridge height. For example, if the finished bridge will be 8 feet high or lower, the path will need to be at least 20 feet wide to get the proper materials to the site. The actual ground area need not be more than 15 feet wide for the equipment to traverse. Consult the bridge company to get more information on the widths needed. When planning the access to each site, place colored flags or stakes to mark sensitive equipment such as sprinkler heads or pipe junctions. The construction team can then avoid driving machinery over them.
It is important to realize that rutting and turf damage will occur on existing courses. Several factors will determine to what extent damage occurs: the equipment used, ground conditions, adverse weather and distances the equipment must travel over fairways or near greens. By planning the access routes properly, you can reduce this damage. However, keep some money in the budget to repair damaged turf, re-seed and back-fill. You'll be better able to determine these costs by consulting the bridge company early in the process and communicating each concern.
Also, when determining routes to bridge sites, plan to have an area in which crews can store bridge materials. This storage area could be a parking lot, fairway or an empty field close to the site or most of the sites. Also consider routes to and from this area before construction begins.
If the bridges are additional or you plan to place them in an area that needs new cart paths, do not pour the cart path right up to the planned starting point of the bridge. Stop pouring about 20 to 30 feet from the bridge. This allows the path to properly tie into the bridge at the correct deck elevation and to allow for possible variations in bridge placement that may become necessary due to terrain. Another rule of thumb is that the distance back from the bridge to which you should pour the cart path is related to the elevation of the bridge. Discuss the specifics with your bridge contractor before pouring the paths.
Before beginning to build Construction begins with a pre-construction walk-through. Experienced companies will insist on this. The walk-through consists of the bridge company's on-site supervisor and yourself walking through and checking the bridge sites. Ask questions to get a feel for what the company will be doing while on site. If changes are made from the initial positioning, re-measure centerlines and check elevations if necessary. Point out access routes at this time. If adjustments need to be made, the bridge company's representative will point them out.
As stated earlier, collateral turf damage to existing courses is inevitable. However, you can minimize it by well-planned routing and proper construction techniques. Prevent additional turf damage by laying down plywood sheets with a minimum thickness of 0.75 inch or using double 0.5-inch sheets. Heavy equipment driving across plywood has less effect on the turf below it. This is especially useful in minimizing damage if the ground is wet.
Communication is crucial during the project. Be available while the crew is working to help solve problems and give answers. Make sure the reverse is true as well. Make sure a representative is available when you need him to keep lines of communication open. This will help to reduce the possibility of change orders due to time delays or incomplete information. You can experience delays by not having information such as the correct elevations or centerlines or by not communicating special requirements upfront.
Experienced bridge companies will keep job sites clean and will keep wetlands areas free of debris on a daily basis. The bridge company will stack the debris and leftover materials at the ends of the bridges. Provide dumpsters or other containers for this waste removal. Typically, bridge contractors do not remove waste or scrap materials from the job site. It is normally your responsibility to arrange to remove this material, but work out the details in advance if you do not want to do this. Most bridge companies will provide this service if you negotiate it upfront.
Instruct maintenance staff to avoid using bridges while under construction. Wait for approval from the bridge company's supervisor before using the bridge for equipment or pedestrian traffic. At times, the bridge contractor may install temporary decking during construction that is not strong enough to bear the weight of equipment. Other components may not be fastened or set, making the bridge unsafe for non-construction personnel.
Once construction is complete, make a post-construction walk-through with the bridge company supervisor. During this walk-through, measure bridges and inspect the work. During the final inspection, look to make sure everything is nailed off, the site is cleaned up and all the bolts on each bridge are tight.
"One word of advice to all superintendents is to know your limits," says River Valley Ranch's Dinkel. "Don't think you are the expert. Make sure you know what the bridge company can do, what it will build, what its work methods are and what it has done in the past."
Whatever your reason for needing a bridge, all of these important points will make selecting a bridge solution and getting the best value an easier process.
Tim Moore is general manager of York Bridge Concepts (Tampa, Fla.).
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