Martin Marietta Materials agreed to buy 20 rock quarries in the southeastern United States for $2.1 billion as the federal infrastructure law boosted demand for sand, gravel and crushed stone used in road construction.

Martin Marietta will acquire quarries and other operations in Alabama, Florida, South Carolina, Tennessee and Virginia, according to the company. Some properties are in Miami and Nashville, Tennessee, both markets that Martin Marietta describes as target areas in a statement.

The seller is closely held Blue Water Industries, based in Jacksonville, Florida. The deal is expected to close later this year.

The federal Infrastructure Investment and Jobs Act of 2021 provided $500 billion to upgrade the nation’s supply of roads, bridges, airport runways, railroads, public transit and other projects. Some projects funded by the law include $292 million for a new Hudson River Tunnel connecting New York and New Jersey and a $250 million replacement of a bridge over the Ohio River that connects Cincinnati with northern Kentucky.

In addition to companies that own and operate rock quarries and cement and concrete plants, heavy construction equipment makers such as Caterpillar and construction managers such as Jacobs and AECOM have also reported significant earnings growth because of the building boom.

Since the infrastructure law took effect in 2022, shares of the two largest companies in the aggregates sector have soared. Since the first trading day in January 2022, Martin Marietta’s stock has climbed 35% to $577.97 per share through Feb. 29. Shares of Vulcan Materials, the largest aggregates company, have risen 24% to $265.77 per share.

Full-year 2023 revenue at Martin Marietta’s aggregates business rose 10.9% to a record $4.3 billion, the company said in a recent earnings conference call. The Raleigh, North Carolina-based company said the value of its ongoing contracts with state and local governments to build highways, bridges and tunnels rose 8% to $113 billion as of Dec. 31, also a record high.

Both Martin Marietta and Vulcan also manufacture finished products made from aggregates, such as asphalt, cement and ready-mixed concrete.

Blue Water Industries is expected to continue to own and operate its aggregates operations in North Carolina and central Florida and its operations at ocean shipping terminals after the sale to Martin Marietta.

Cravath, Swaine & Moore was legal counsel to Martin Marietta. Wachtell, Lipton, Rosen & Katz was counsel to Blue Water, and Greystone Group was its financial adviser.