Thinking about buying agricultural land in Waimea so you can grow, build an ADU, or both? You’re smart to dig into the details first. Between state land-use rules, county ADU updates, and farm plan tax programs, the path to value is clearer when you know the playbook. This guide walks you through what you can build, how ag tax programs work, what drives price in Waimea, and a step-by-step diligence list. Let’s dive in.
Start with the rules in Waimea
Hawai‘i sets the baseline for what you can do on agricultural land. The Agricultural District allows farming, livestock, farm dwellings, and related uses under HRS §205‑4.5. Counties add zoning and permitting on top of that.
In Hawai‘i County, zoning like A‑5A, A‑10A, or A‑20A controls density, setbacks, and permitted uses. Always confirm the exact zoning and permitted uses for your parcel with the County’s Planning Division resources. If any portion of the property is in the State Conservation District, improvements may require permits through DLNR’s OCCL; review the OCCL permit process early.
ADUs on ag land: what changed in 2024
Hawai‘i County expanded ADU allowances in 2024 (often referred to as Bill 123). Local reporting notes that ADUs are now permitted in additional zones, including some agricultural areas, with unit caps and size limits (commonly cited at 1,250 square feet per unit) and restrictions on short-term rental use. See an overview in Spectrum’s Bill 123 coverage.
What this means for you:
- Eligibility is parcel-specific. Confirm your zoning and any overlays before you underwrite ADU income.
- Caps matter. News reports indicate up to three ADUs per lot where allowed, with unit size limits.
- Short-term rental use is limited. Many ADUs cannot be used for STRs, or only one may be eligible.
- Infrastructure drives feasibility. Water, septic, and access must support any added units.
Bottom line: ADUs can boost long-term rental income or house farmworkers, but you should verify the rules and your site’s capacity before you buy.
Farm plans and ag tax programs: how they work
Hawai‘i County restructured its agricultural tax programs into three tracks: Community Food Sustainability (CFS), a 3‑year dedicated program, and a 10‑year dedicated program. Each route lowers assessed value if you document bona-fide agricultural use. Start with the Real Property Tax Office’s ag program resources and forms.
A county “farm plan” is your roadmap. It typically includes a parcel map, crops or livestock plan, acreage, production schedule, water sources and infrastructure, expected receipts, and sale or donation channels. Some programs accept alternate documentation like USDA certifications or conservation plans. Reporting has highlighted examples of minimum receipts or donation thresholds in certain tracks; review context in Civil Beat’s coverage of program changes, then confirm current figures with the County.
Deadlines are time-sensitive. Recent updates referenced an initial application deadline for owners not in prior programs and a later transition deadline for owners in older programs. See a summary of timing in this Hawai‘i Life program deadline update, and verify the current dates with the Real Property Tax Office.
Quick farm plan prep checklist:
- Define your agricultural activity (crops, livestock, or both) and acreage.
- Map water sources and needed infrastructure (fencing, irrigation, barns).
- Build a simple production and sales or donation schedule.
- Gather any certifications or receipts you’ll use to qualify.
What drives value in Waimea ag land
Statewide, the 2022 Ag Census shows fewer farms and less land in farms than in 2017, while the value of agricultural products rose. That mix, plus limited developable land on the island, shapes pricing power. Review the statewide context in the 2022 Hawai‘i Ag Census summary.
In Waimea, value is hyper-local. Key drivers include elevation and climate, access to county water or reliable wells, road access, soil productivity and any Important Agricultural Lands (IAL) mapping, and proximity to Waimea town and the Kohala Coast. You can explore IAL mapping via the Land Use Commission’s IAL map resources. Local landowner actions also matter: Parker Ranch influences supply and community planning; learn more on Parker Ranch’s land page.
How ADU policy affects price: Expanded ADU allowances can increase long-term rental potential and make smaller, well-located parcels more efficient. Short-term rental limits and infrastructure costs may cap upside, so tie your underwriting to actual permitted uses and realistic build budgets. For rule context, see Bill 123 reporting.
Due diligence checklist for Waimea ag parcels
Use this checklist to structure your evaluation:
- Verify state land-use district and county zoning, including permitted uses and setbacks (start with the County’s zoning resources).
- Check for Conservation District areas and required permits through DLNR OCCL.
- Confirm water and wastewater solutions (county meter availability, well feasibility, septic capacity) and the impact on any ADU plans.
- Align your ADU concept with allowed unit counts, size caps, and STR limits; review Bill 123 coverage.
- Assess eligibility for CFS, 3‑year, or 10‑year ag programs and start your farm plan documentation.
- Note any IAL mapping or soil productivity factors that could influence use and value (see IAL maps).
- Estimate site and infrastructure costs (roads, power, fencing, irrigation, barns) against your operating plan.
- Pull recent, truly comparable sales in Waimea that match size, access, utilities, and improvements.
- Screen for cultural or historic resource considerations early if applicable.
- Line up your team: County Planning and Real Property staff, a land use consultant or attorney if needed, and a local agent experienced with Waimea ag parcels.
If you want a grounded read on a specific parcel’s ADU potential, farm plan path, and likely value range, connect with a local advisor who lives these details day to day. Reach out to Noelani Spencer for a Waimea-first perspective and a clear action plan.
FAQs
Can you build ADUs on agricultural land in Waimea?
- Possibly, depending on your zoning and overlays; 2024 updates expanded ADU allowances into some ag zones with unit and size caps, and limits on short-term rental use (verify with County Planning and see Bill 123 reporting).
What does a Hawai‘i County farm plan need to include?
- A parcel map, defined crops or livestock, acreage, production schedule, water and infrastructure details, and expected receipts or donation channels (see the County’s Real Property Tax resources).
Do ag tax programs actually lower property taxes?
- Yes, dedicated agricultural use programs generally reduce assessed value for qualifying acreage, but you must document bona-fide agricultural activity and maintain compliance (see Real Property Tax Office guidance).
Are there minimum income or donation thresholds to qualify?
- Reporting has noted examples like annual receipts or donation minimums depending on the program, but details change; review Civil Beat’s overview and confirm current figures with the County.
What deadlines should buyers know before closing on ag land?
- Application and transition timelines for the new programs were updated in 2024–2025; see this Hawai‘i Life deadline update and verify current dates with the Real Property Tax Office.
How do Conservation District boundaries affect building plans?
- Conservation subzones can limit or slow development; many activities need OCCL approvals, so check the OCCL process early and adjust your scope accordingly.
