No city hall? When unincorporated Jefferson or Arapahoe County wants a grading permit for your turf job

Places like Columbine, Ken Caryl, Fairmount, Applewood, Holly Hills, Dove Valley and Foxfield share one thing

None of them is an incorporated town. Columbine, Ken Caryl, Applewood and Fairmount sit in unincorporated Jefferson County. Dove Valley and Foxfield-area unincorporated parcels, along with most of the county outside its cities, fall under unincorporated Arapahoe County. Either way, there's no city planning counter reviewing a backyard project the way Denver, Aurora or Lakewood would. The county itself is the reviewing authority, and each county writes its own trigger for when digging up a yard needs a permit first.

That matters for a turf job because the work is, by definition, land disturbance: the old lawn comes out, base material gets brought in and compacted, and the ground gets reshaped to the layout. Whether that crosses into permit territory depends on how much ground is disturbed and which county's code applies to the parcel. It also depends on what else is happening on the property that same season, which is where both counties' rules get less intuitive than a simple square-footage number.

This page covers two of the Denver metro's unincorporated counties. If your property is in Douglas, Adams or Boulder County, the rule is different and we haven't verified it yet — see the note near the bottom of this page.

Jefferson County: the line is 0.5 acres, and it isn't always your call

Jefferson County's Zoning Resolution, Section 16, Land Disturbance (amended 6-10-25), states that land disturbance activity requires a Grading Permit if "the disturbed area is equal to or greater than 0.5 acres." Half an acre is about 21,780 square feet, so a typical backyard turf installation, taken on its own, usually lands well under that line.

The code doesn't stop there, though. The exemption for projects under 0.5 acres carries a condition most homeowners never see coming: "Any series of related projects or connected projects on one site, which together exceed the 0.5 acre limitation shall be considered a single project and shall be required to obtain a Grading Permit." If turf is one piece of a bigger year — a pool, a patio expansion, regraded drainage, a driveway — the county can add those disturbed areas together as one project. A job that looks small in isolation can trip the threshold once it's counted alongside everything else happening on the same site.

There's also a rule that survives even a clean exemption. The code says exempt land disturbance "must still be in compliance with the performance standards set forth in this section, unless specifically stated otherwise." Falling under 0.5 acres gets you out of the permit application, not out of doing the grading and drainage work correctly.

The practical takeaway is that the 0.5-acre line isn't really about turf square footage in isolation — it's about everything disturbed on that site as one project. A homeowner planning a putting green this spring and a drainage regrade next fall, on the same lot, should ask the county whether Jefferson treats those as connected before assuming either one is exempt on its own.

The one Jefferson County exemption that doesn't apply to septic work

Jefferson County exempts some trenching from permit requirements — utility lines, communication conduit, well drilling — when the total disturbance is under an acre. But the same provision draws a specific line around septic: "Construction activities associated with the installation of the onsite wastewater treatment system (OWTS) shall not be exempt." It's a narrow exception inside a narrow exemption, and it's not about turf directly, but it's worth knowing if a turf job on a property with a septic system runs anywhere near the tank or leach field. That's a conversation for the county, not a guess made on site.

Arapahoe County: no acreage number in the code itself, but the default runs the other way

Arapahoe County's Land Development Code takes a different shape. Chapter 5's Grading, Erosion and Sediment Control (GESC) Permit section states that these regulations "shall apply to all property within the unincorporated areas of Arapahoe County" and that "No land disturbance shall occur on any property, unless otherwise exempted via provisions in the GESC Manual... without first obtaining a GESC permit from the County."

Rather than writing a size threshold into the Land Development Code, Arapahoe County pushes the exemption list into a separate document, the county's Grading, Erosion, and Sediment Control Manual, which the code incorporates by reference. The code itself says plainly: "The Projects that require a GESC permit and the Projects that do not require GESC permit are described in the GESC Manual, as amended." We opened the Land Development Code and did not open the GESC Manual, so we can't state Arapahoe's own acreage or square-footage cutoff here. If your parcel is in unincorporated Arapahoe County — Dove Valley and much of the Foxfield-adjacent area included — that's a question for Arapahoe County Public Works and Development before you schedule.

One line in the code applies regardless of the answer: "Even if a Project is exempt from GESC permitting, BMPs shall still be required for any clearing, grading, or land disturbing activities in accordance with the standards set forth in the GESC Manual, as amended." The code separately requires "construction Best Management Practices (BMPs) to ensure that existing soils are retained on their site, and are not deposited or discharged onto adjacent properties." Permit or no permit, keeping your soil on your lot is not optional in unincorporated Arapahoe County.

What this means for scheduling a turf job

Before you set a start date on a putting green, a full backyard turf conversion, or a pet-turf run in unincorporated Jefferson or Arapahoe County, add up everything that will disturb ground on your property this season — not just the turf. In Jefferson County, ask whether your total, combined with any related work, stays under 0.5 acres. In Arapahoe County, ask Public Works and Development directly whether your project needs a GESC permit under the current Manual, since the Land Development Code sends that question there rather than answering it in the code text.

Either way, a permit determination — or an exemption — doesn't remove the responsibility to control erosion and keep soil on your own lot while the work is underway. That part of both counties' rules applies whether or not paperwork is required.

We do a free visit to measure your yard and check the ground before anything is scheduled. That visit tells us the disturbed area a project will actually involve, which is the number you need before calling the county. We build a custom layout you approve, with 13 years' experience behind it. Call 303-349-2368 to start.

This question comes up most on residential turf and backyard putting green jobs, where excavation and base work are part of the project either way. For state-level rules that sit above the county code — including HOA turf restrictions and Colorado's own turf statutes — see our guides to Colorado artificial turf law and Colorado HOA turf rules.

What we haven't confirmed yet

This page covers Jefferson County's Section 16 land disturbance rule and Arapahoe County's Land Development Code Chapter 5 GESC permit provisions, as written in the documents we opened. We have not opened Arapahoe County's GESC Manual, so we can't state its specific exemption thresholds here — that's a question for Arapahoe County Public Works and Development. We also have not researched Douglas County's grading and erosion rules (relevant to Highlands Ranch, Castle Pines and Sterling Ranch), Adams County's, or Boulder County's, including Gunbarrel. If your property sits in one of those counties, check with that county's planning or public works office directly; this guide doesn't cover them yet.