Land Drainage Contractors Association

EUROPIPES UK - GOING WAY BEYOND EUROPE

The Estadio Paquito Montaner Baseball Park and Stadium in Ponce, Puerto Rico, is home to a league of seven baseball teams and is used for winter training by many United States Major League Baseball players. The park is also a track-and-field complex where different interuniversity sports activities are held during the year. Constructed in the 1930s, the stadium is designated as a historic facility in Puerto Rico. However, drainage problems at the park were resulting in the possible withdrawal of the winter baseball-training schedule by the major leagues, a crucial financial liability for the park.

To effectively continue use of the facilities, improvements were needed to the stormwater management and drainage system that would keep the playing fields and track in usable condition after a rain. These improvements were included in a planned renovation and expansion of the facility, which involves a complete construction of a new track and field area and other athletic facilities.

The Past Problem

After even very small amounts of rain, the surface area of the park started to deteriorate; the playing field turning humid and soggy, making it unusable. The old drainage system was constructed with 4-in. black perforated pipe surrounded by gravel. The perforated pipe did not have the capacity to drain the large volumes of stormwater with the amount of surface area it was covering. In addition, the perforated pipe clogged with sediment buildup, dramatically reducing capacity.

In the last 10 years, four hurricanes have struck the island. With even normal rainfall in Puerto Rico intense enough to trigger flooding of the field, the capacity and operation of any future system needed to be well researched.

Working Toward a New Solution

The first priority for the design engineer, Jose Rafael Bernabe Acuna, P.E., of JRBA Consulting Mechanical Engineers in San Juan, was to eliminate the flooding possibility at the park. To do so, he moved the storm drain connection and reconnected the discharge of the existing storm sewer system to another point in the line. This would prevent the park and its operation from being directly affected if the system started to flood. Acuna then began to explore options for an efficient and effective storage system for the facility.

In an effort to avoid future system failure and to eliminate the potential financial hardship of game and event cancellations at the park, Acuna advocated and searched for a new approach. His goal was to find a solution that would incorporate advanced technology and the latest stormwater management design methods.

A subsurface chamber system design was chosen to drain the field faster and more effectively and offer a longer life span than an old-fashioned trench-and-pipe installation. The documented longevity of the performance of this type of system convinced park management it would not have to renovate the stormwater management system again for decades, if ever.

System Details

This state-of-the-art stormwater management system Acuna designed self-drains and then discharges to the storm sewer once the rain event is over. The system uses 2,600 StormTech SC-310 chambers under the baseball park for general drainage of the stadium. A municipal grant funded most of the design and installation of the system, supplemented with a small amount of federal funding that helped pay for the park renovation.

StormTech chambers were selected because, when used in a bed system, they provide managed infiltrated runoff over a wide area. “The StormTech SC-310s are ideal for low-rise, wide-span solutions because they create more infiltrative surface area. They also provide more void space to store and infiltrate water than the outdated stone and pipe trench drain technique,” notes Alberto Davila of Sani-Plant in San Juan, the Puerto Rican distributor for StormTech chambers. The system is designed so that water drains directly through the upper soil level and infiltrates into the StormTech chambers without catch basins or inlet structures. Instead of an inlet, the engineer designed for a 6-in. layer of highly permeable sand for the root zone of the grass and 12 in. of stone above the chambers. Water is detained, allowing optimum groundwater recharge and outlet to the municipal drain system. A product with a large infiltrative footprint, such as the smaller StormTech chamber, was the most effective for the stadium because the area’s soils have poor infiltration rates.

Because the developers wanted to ensure that the system would drain between rain events, the storage capacity of the system was kept at its fullest. “This was a concern because athletic fields are fertilized, and when it rains, the runoff can suspend and carry harmful pesticides off-site,” Acuna says. With the chambers being used and inlet through permeable sands, these pollutants have a chance to go through a filtration process inherently provided by the upper soil layer. While the system is outlet to a municipal system, StormTech chambers allow a good portion of runoff to infiltrate again through foundation soils, providing additional treatment.

Installation

The gold-colored chambers reflect the hottest spectrum of the sun’s energy, so they remained cool in Puerto Rico’s hot sun. This allowed the installers to work faster and also provided a structural benefit. Typical black plastic construction products can reach temperatures close to 200êF when exposed to intense sunlight. Thermoplastics, especially polyethylene, can lose a significant amount of their structural integrity while at elevated temperatures. The wide expanse of this project required heavy equipment to travel across the bed before it was fully covered. Black plastic products are most vulnerable during these conditions, and special precautions sometimes are required. StormTech’s chambers, designed with AASHTO required safety factors and manufactured from yellow virgin polypropylene, kept their cool under these extreme conditions. Work continued throughout the day without any costly delays. Approximately 62,000 ft.2 of playing field and adjacent area use the subsurface chambers for drainage. “Since the installation, there have been no game cancellations, even when there was a rain event an hour before the scheduled game start time,” Davila says. “Not only does the park drain, but the field is dry in a very short period of time.” This new stadium stormwater management design is being used as a pilot project, with other stadiums looking at this project as a potential model to copy.

“We were all impressed by the ease of the installation,” Acuna remarks. “The installing contractor, Rama Construction of Ponce, Puerto Rico, was able to unload and install one full trailer load every four hours with a small crew of four workers.”

Maintenance

Because these chambers are not inlets with traditional catch basins or yard drains, there are no maintenance requirements. The runoff is being collected from a vegetated athletic field without slopes, so sediments are not carried away or accumulated. With this type of inlet design in this application, the chambers should be virtually maintenance-free.

EUROPIPES (UK) Ltd.
Buttfield Road, Howden,
East Yorkshire,
DN14 7DY.
Tel: 01430 430529.
Fax: 01430 432084
Email: d-axup@hotmail.com
Web-site: www.europipes.co.uk
Contact: David Axup.