The New Seattle Sounds FC Training Fields

The Seattle Sounders Football Club celebrated their 50^th anniversary last month at their new headquarters and training facility at Longacres: The Providence Swedish Performance Center & Clubhouse.

The transformation from office parking lot to training fields—two natural grass fields and two artificial turf fields—took less than a year. Venture General Contracting oversaw both the remodel of the offices and the construction of the fields. Nearly 80,000 tons of Washington Rock’s materials were shipped to the fields throughout construction.

In this photo essay, follow the process of turning Longacres into an iconic training facility. Venture Senior Superintendent Dan Weese provides insights about the project throughout the article.

March 2023: Pre-Construction

The lower parking lot of the original Longacres facility (center of the photography) marks where the future fields will be. The building next to the parking lots is the future Seattle Sounders headquarters. Photographer: Tim Rice.

May to Early June 2023: Clearing

The lower parking lot is demoed, and the field is cleared. One section of parking lot is retained to be used as a staging area for construction equipment and materials. The staging area will eventually become Field 2, a natural grass field. Photographer: Tim Rice.

Mid-June to Early July 2023: Materials Imported

Chamber rock is stockpiled in the staging area while the fields are excavated and graded. The rock will be installed under the fields as part of a drainage system. From July to October 2023, Washington Rock ships over 30,000 tons of chamber rock to the job site. Photographer: Tim Rice.

Meanwhile, excess organic materials are exported offsite. All of this work takes place at night to avoid heavy traffic. Trucks ship materials offsite and return with chamber rock. Photographer: Tim Rice.

July to August 2023: Grading & Drainage

The initial goal is to provide the Sounders a grass field and a synthetic turf field by January 2024. So efforts focus on finishing Field 1 (a grass field) and Field 3 (a synthetic turf field) first.

Grading takes place on Field 1 using 1-¼” Minus Tailings from Washington Rock (bottom left corner). Meanwhile, flood-plain chambers, the yellow pipes on the right-hand side of the photo, are being installed on Field 3 on top of a bed of chamber rock. Material continues to be exported from Field 4 (top right). Field 2 is still being used as a staging area (center left). Photographer: Tim Rice.

In early August, chamber installation on Field 3 is complete. Chamber rock is conveyed on top of the chambers in sections. Because the fields sit on a flood plain, FEMA regulations require displaced soil to be replaced with water storage, hence the chambers. Photographer: Tim Rice.

By mid-August, the chamber rock on Field 3 has been topped with an impermeable liner. Then tailings are placed on top of the liner. Senior superintendent Dan Weese explained, “When it rains, the water goes through the turf, it hits the liner and goes over it and gets collected. It gets taken to the ponds. Then if the ponds get too high, it can flow back in underneath the fields [into the flood-plain chambers].”

Throughout the project, Washington Rock will ship over 24,000 tons of tailings to the jobsite. Photographer: Tim Rice.

While tailings are installed on Field 3 (center bottom), chambers are installed on Field 4 (far right). Soil is “farmed” on Field 1 (far left) to dry it out until it reaches a compactable stage. Photographer: Tim Rice.

September 2023: Fine Grading & Flat Drains

While Field 3 meets industry standards, FIFA (the international governing body for association football) has even more stringent requirements that require more fine-tuned grading. “You have civil grading to civil tolerances, and then you have our field builder coming in and taking it [to FIFA’s] tolerances. And they’re drastically different,” Dan Weese explained. “So a civil [field project] is allowed to be within a 10th of an inch. And [FIFA fields] are down to four-hundredths of an inch. So they’re regrading, filling, regrading.”

In mid-September, the slope of the field is measured with string lines and lasers. Then the piles seen in the photo above are strategically placed to bring the field to the correct tolerances. This material is then graded. Photographer: Tim Rice.

On Field 2 next door, a special rootzone sand mix is shipped in. The sand mix made by Walrath contains sand from Washington Rock. The mixture will be used on the natural grass fields, Field 1 and Field 2. Photographer: Tim Rice.

While fine grading occurs on Field 3 (bottom middle), chamber rock installation has been completed on Field 4, and permeable aggregate base course installation has begun (far right side). Field 1 (far left side) has been graded and covered with landscape fabric. Flat drains have been installed on top of the landscape fabric and are in the process of being covered with pea gravel. This subsurface drainage system will lie beneath the grass fields. Photographer: Tim Rice.

Late September 2023: Rootzone Sand Mix

The rootzone sand mix is conveyed into piles on Field 1 (above), covering the pea gravel. A dozer then works from the top of the sand piles and pushes them outward. This process prevents the dozer tracks from pulling up the pea gravel or mixing the pea gravel and sand together.
Photographer: Tim Rice.

Bulldozers grade the sand mixture on Field 1 (above). Looking closely, you may be able to see white sprinkler pipes poking out of the sand mixture. Once all of the sand mix is in place, it must be thoroughly watered over a few days. “You absolutely have to soak that sand in to get it to compact and fully set,” Weese said. Photographer: Tim Rice.

October 2023: Permeable Aggregates & Grass

A hauler for Washington Rock delivers permeable aggregate base course to Field 3 (above). Over four months, Washington Rock will ship nearly 9,000 tons of permeable aggregate base course to the job site. Photographer: Eve Hart.

With the soil finished on Field 1 (top of the photo above), an impermeable barrier has been installed on Field 3 (center of the photo above). Flat drains are placed on top to provide subsurface drainage. A dozer works on spreading out permeable base course. Permeable base course is a foundational material that provides better drainage than typical base course. As a whole, the synthetic turf system allows water to flow through the upper layers into the gravel base and the flat drains. Photographer: Tim Rice.

A dozer pushes permeable base course toward the edges of Field 3 (above). Photographer: Tim Rice.

The permeable top course on Field 3 is compacted (above). Nearly 3,000 tons of permeable aggregate top course will be used on the synthetic turf fields. Photographer: Eve Hart.

By the end of September, grass has been installed on Field 1 (above, left) and permeable aggregate top course has been installed on Field 3 (above, bottom center). Subsurface drainage from Field 1 is being extended on to Field 2 (above, top center). Photographer: Tim Rice.

Field 1 before grass installation (top left) compared to after grass installation (top right). The bottom photo shows the completed grass installation. Photographer: Eve Hart.

Early November 2023: E-Layer

Field 3 is paved with E-Layer, a combination of rubber and E-layer stone from Washington Rock Quarries (above). Photographer: Tim Rice.

Washington Rock’s E-Layer Stone is emptied into a hopper to mix it with paving material to create E-layer (top left). E-layer is short for “Elastic Layer.” The E-layer mixture is installed on top of the permeable aggregate top course (top right). The paving machine runs back and forth in lines (bottom). Photographer: Eve Hart.

The natural grass of Field 1 contrasts with the E-layer of Field 3. Photographer: Eve Hart.

Mid-November 2023: Sand Mix on Field 2

Following the process for Field 1, a mountain of rootzone sand mix is spread over the pea gravel on Field 2 (above). Photographer: Eve Hart.

A dozer operator pushes rootzone sand mix over the pea gravel on Field 2 (above). Photographer: Eve Hart

December 2023: Turf & Infill on Field 3

Synthetic turf is rolled out on Field 3 (above). Workers stretch out each roll to set it perfectly in place. Photographer: Eve Hart

Workers seal glue down the edges of the field (above, top left). The synthetic turf contrasts with the E-layer it sits on top of (above, top right). Workers secure the seams between lengths of turf (above, bottom). Photographer: Eve Hart.

After field installation is complete, infill sand and cork are spread on Field 3 (above). The mixture acts like topsoil, keeping grass blades upright and cushioning gameplay. Photographer: Eve Hart

In late November, Field 1 (above, bottom) and Field 3 (above, middle right) are completed and ready for practices. Sand mix has been completely installed on Field 2 (above, middle left). Photographer: Tim Rice.

January 2023: Grass on Field 2 and Permeable Aggregates on Field 4

Sod installation is completed on Field 2 (above, middle right). Permeable aggregates are installed on Field 4 (above, bottom). Photographer: Tim Rice.

February 2023: E-Layer on Field 4

E-layer is installed on Field 4 (above, bottom right). Photographer: Tim Rice.

March 2023: Mission Accomplished

All four fields have been completed. Photographer: Tim Rice.

Before & After

After just 10 months of construction, all four fields are completed. Compare before (top left) to after (top right). The bottom photo above shows athletes actively practicing on Field 3.

The goal of the project, Weese explained, was to give teams a place to play in the first quarter of 2024. Mission accomplished.

This story is not endorsed or sponsored by Seattle Sounders FC. Special thank you to Dan Weese for the knowledge that made this article possible. Thank you also to Venture General Contracting for granting the use of construction photos. You can watch the Seattle Sounders video about the construction process on YouTube.

You can see more stats on our project page. To learn more about Washington Rock’s sports field aggregates, check out our blog article, “The Foundation for a Great Game.”

Infill Sand
Building the Seattle Sounders FC Training Fields: A Photo Essay