The developer partnering with Amazon on its second headquarters is looking to add new housing near HQ2 to help support the area's growth.

JBG Smith announced Monday it filed plans with Arlington County to add nearly 1,000 units to its RiverHouse community in Pentagon City, with plans to begin construction next year.

The 36-acre RiverHouse development, at the intersection of Army Navy Drive and South Joyce Street, includes 1,670 existing units across three high-rise towers built in the 1950s and 1960s. JBG Smith predecessor Vornado had planned to add over 1,000 units to the site prior to the 2017 merger of its D.C. arm with The JBG Cos., and now the merged company is returning to the county with a new vision for the site.

The latest plans call for two six-story multifamily buildings totaling about 750 apartments on a site in between two of the existing rental towers. The new buildings would include central courtyards and 30K SF of ground-floor retail.

The remaining roughly 250 units would be built as for-sale housing and include traditional townhouses and two-over-two townhouses. They would be constructed on the southern portion of the site near the existing single-family community.

JBG Smith Executive Vice President Andy VanHorn said the developer focused on submitting a plan that respects the character of the surrounding community and includes a mix of rental and for-sale housing opportunities to meet the area's growing demand.

"It is our goal to deliver additional housing units concurrent with Amazon's occupancy of its new headquarters to help meet anticipated new housing demand and mitigate upward pressure on rents in National Landing," VanHorn said in a release.

The filing comes as Amazon is moving through the site plan review process for the first two new office towers at its HQ2 campus. JBG Smith is selling the land for the office project to Amazon and is staying on as the development partner, property manager and retail leasing agent.