WAYLAND, MA — Recent heavy rains washed pieces of Wayland High School's new crumb rubber football field into nearby waterways, exacerbating concerns about a material that residents have raised environmental questions about.

Facilities Director Ben Keefe told the Wayland School Committee on Thursday heavy rain during storm Ida last week washed water and crumb rubber into a filter system and clogged it. Wayland got more than 5 inches of rain in just a few hours during that storm.

When Keefe opened one of the filters to drain the flooded field after Ida, he inadvertently unleashed a "gusher" that last 45 minutes, sending a mixture of rubber and water out a nearby drain.

"It's a big mess, but we didn't lose that much crumb rubber," he said.

Keefe said this is the first time the 16-month-old field's drain system has clogged.

Keefe estimated that about 99 percent of the crumb rubber and water mix that flowed off the field was captured in a swale before it could reach open wetlands near the Sudbury River. Some of the crumb rubber did make it into the the open water, he said.

Images of the flooded field showing mounds of black rubber pieces were posted widely on social media over the past week. Wayland Conservation Commissioner Sean Fair took multiple videos of a makeshift cleanup where he used a basket meant to hold flowers to collect the rubber.

(The video at the top of this story shows Fair cleaning up crumb rubber inside a swale, not in open wetlands.)

Wayland has proposed building more crumb rubber fields as the town struggles with a dearth of athletic facilities. Town Meeting this spring voted down a proposal to build turf fields at the Loker Recreation Area, and a special Town Meeting in October will decide if the town will place a moratorium on synthetic fields.

Some residents question whether crumb rubber is a factor in Wayland's PFAS problem. Apart from washing away, the rubber can blow around during high winds. Town officials have said only PFAS-free "virgin" crumb rubber would be used to build new fields, although that type of rubber may still contain "chemicals of concern," according to a Massachusetts Toxics Use Reduction Institute assessment.

Keefe told the Wayland School Committee the town plans to construct a larger filter at the field to prevent any future overflows into either the swale or wetlands.

Town Administrator Louise Miller said the recent flood at the high school field provided an opportunity for the town to test if the crumb rubber is contributing to the PFAS problem. Water that came off the field after Ida has been sent for lab testing, she said.

The Happy Hollow Wellfield, the town's main drinking water source, has tested above the state's 20 parts-per-trillion threshold for PFAS contamination in recent months. The town has not found an exact source of the contamination, but several wells in the field are located near or directly under the high school. Recent tests have found a former septic tank at the school may have contributed to PFAS contamination exacerbated by this summer's heavy rains.

"The upward trend in concentration may be a result of anomalously high precipitation in summer 2021, thereby raising the groundwater elevations across the area and perhaps ‘flushing’ PFAS laden biomatter remaining in the soil absorption system of the former wastewater discharge location," a summary by Weston & Sampson Engineers said.

The town is in the process of installing a filter system for the Happy Hollow Wellfield, which could be online by October.

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