A 112-acre stretch of land near Memmen Park in Castle Rock is on the verge of becoming 402 new homes, and residents on quiet, dead-end streets like Ash Avenue and Valley Drive are bracing for what comes next. The Chateau Valley development, decades in the making, is now close to receiving final approval after years of slow progress, with the project's road extensions and new rooftops set to butt up directly against existing subdivisions on three sides.
According to CBS Colorado, the Memmen family land has been earmarked for development since the 1980s, and the property was annexed into Castle Rock decades ago. The plan, put together by Highline Engineering & Surveying, calls for roughly 400 homes — a mix of houses and duplexes — on land east of Memmen Park, north of the Baldwin Park subdivision, and south of the Southridge townhome subdivision.
Town of Castle Rock public notices detail the project down to the unit: 254 single-family detached homes and 148 single-family attached duplex units across the 112-acre parcel, with 50.2 acres set aside as public open space. Developer Russell Hall, general manager of Chateau Valley LLC, told CBS Colorado the project is intended to blend residential development with the properties already surrounding it, and said it will also provide more affordable housing options for Castle Rock.
Dead-End Streets Set to Connect
Not everyone on the surrounding blocks is thrilled. Ash Avenue neighbors oppose the development, largely because of what the road extensions mean for their street. Chateau Valley's plans call for extending dead-end roads, including Valley Drive and Ash Avenue, to connect them to the new subdivision effectively.
Scott Gricks, a neighbor quoted by CBS Colorado, warned that Ash Avenue could become a thoroughfare used by passing traffic rather than the low-key residential street it is today. Maureen O'Reilly, who lived on Ash Avenue for nearly 45 years, described a street with older homes, on-street parking, and children playing outside — the kind of neighborhood character residents worry won't survive heavier traffic. O'Reilly has since sold her Ash Avenue home, according to the outlet's reporting.
Hall pushed back on the traffic fears, telling CBS Colorado that side-street and Valley Drive connectivity would keep the development's traffic impact reasonable. He also argued the road extensions would improve access to existing homes and cut down emergency vehicle response times in the area. The development is also slated to build a regional trail and preserve about 50 acres of open space.
A Timeline Decades in the Making
The project's path to a vote has been anything but quick. Castle Rock held its final neighborhood meeting for Chateau Valley on Monday, and the Castle Rock Planning Commission is scheduled to formally review the plans on Thursday, ahead of a Castle Rock Town Council public hearing set for September 1, per municipal hearing schedules. The Planning Commission's role is advisory, recommending before the Town Council casts the final vote.
The political history around this particular parcel has not always been smooth. Back in November 2021, the Castle Rock Town Council voted 4–3 to remove a Historic Preservation Commission member after she emailed developer Highline C.M. Inc. voicing concern over developing Chateau Valley's “lush land” while citing her town board credentials, as reported by Colorado Community Media. That episode sparked debate over how far local advisory board members can go in voicing personal opinions on land-use matters.
Why Castle Rock Can't Just Say No
Neighbors are concerned about traffic and water from the incoming development, but town planning records help explain why officials have limited room to simply reject it. As of Q1 2026, 95.9% of Castle Rock's 56,693 approved residential zoning entitlements were created in or before the 1980s, according to Town of Castle Rock planning records — meaning Chateau Valley's decades-old zoning creates binding legal development rights that current town leaders are required to honor. Only 31,766 of those approved units had actually been built by early 2026, leaving a large backlog of legally entitled but unbuilt homes still working their way through town.
On the water front, Castle Rock has planned to provide water to the development for years, per CBS Colorado's reporting. Castle Rock Water has invested roughly $270 million in long-term renewable water infrastructure, including a $75 million expansion of the Plum Creek Water Purification Facility, with targets of 75% renewable water by 2050 and 100% by 2065. The utility's push away from deep, nonrenewable groundwater aquifers toward surface and recycled water sources is a direct response to the kind of scarcity fears residents have raised about projects like Chateau Valley.
Those fears were formal enough to generate an online petition on Change.org back in January 2024, in which residents sought to block or rezone Chateau Valley, citing rapid town expansion, dwindling water resources, and traffic safety on streets without adequate sidewalks. Chateau Valley isn't an isolated case, either — CBS Colorado has reported it is one of three nearby developments, alongside the proposed 500-plus home Founders Vista project and the 114-home Oaks project, that could collectively add more than 1,000 new residences to eastern Castle Rock.
Part of a Much Bigger Growth Wave
Chateau Valley's 402 lots are modest compared to some of the master-planned communities reshaping other corners of Castle Rock. Hoodline previously reported that homebuilder Taylor Morrison purchased 256 lots in west Castle Rock's Dawson Trails development, a project slated for up to 5,850 homes and 3.2 million square feet of commercial space anchored by a Costco. The town's population reached an estimated 88,309 residents in Q1 2026, according to town demographic data — about 56% of its projected maximum buildout population of 157,607, following growth of more than 51% between the 2010 and 2020 federal censuses.
The town has tried to pair that growth with preservation efforts elsewhere. Hoodline reported in May that Castle Rock prepared to open Lost Canyon Ranch, a 681-acre canyonland open space the town purchased in 2024 for $15 million — its largest land preservation acquisition to date. Town officials have pointed to that kind of buffer-building as central to the 2030 Master Plan even as infill projects like Chateau Valley move toward final votes.
For now, Chateau Valley's fate rests with the Planning Commission's review Thursday and the Town Council's public hearing on September 1. Whether the road extensions, open space, and water investments are enough to ease Ash Avenue's concerns likely won't be clear until the council casts its final vote.
