Before You Buy the Land: Why Feasibility and Due Diligence Still Decide California Projects

A feasibility study is a pre-purchase analysis of what a specific property can hold, what it will cost to develop, and how it will get approved. Due diligence is the investigation that feeds it. In California, where land is expensive and approvals are closely watched, this work is the cheapest protection a buyer has before committing capital.

The costliest line in a development budget is often the one nobody priced: the constraint found after closing.

• A fault zone that removes part of the buildable area.
• An off-site sewer extension missing from the pro forma.
• A wetland that knocks the project off a streamlined approval path.

California has added several fast approval routes for housing since 2023, and more took effect this year. That makes early site investigation more valuable, not less, because every fast route has eligibility conditions tied to the land itself.

What is the difference between due diligence and a feasibility study?

Due diligence is the structured investigation of a property before the purchase is final: title, survey, zoning, environmental condition, natural hazards, and utilities. Its job is to replace assumptions with documented facts.

A feasibility study uses those facts to answer the harder questions.

• What can be built here?
• What will it cost?
• Which approval path fits, and how long will it take?

A useful study ends with a clear recommendation to proceed, renegotiate, or pass. Our feasibility study services page describes what that deliverable covers.

What should a California feasibility study check?

Good feasibility work covers three kinds of risk, and a serious problem in any one can end a deal.

• Legal and regulatory.
  • The preliminary title report and recorded easements
  • The general plan and zoning designations
  • Overlay districts
  • The entitlement path the project would follow

  An ALTA/NSPS land title survey ties the title commitment to conditions on the ground, including easements, encroachments, access, and boundary lines.

• Physical.
  • A topographic survey of grades, drainage paths, trees, and existing improvements
  • Geotechnical conditions
  • A Phase I environmental site assessment
  • Where the site falls on FEMA flood maps, California Geological Survey earthquake fault zone maps, and CAL FIRE fire hazard severity zone maps

  Add the location and capacity of water, sewer, storm drain, and dry utilities at the property line.

• Financial. An opinion of probable cost for site work, off-site improvements, and fees, tested against what the market will pay.

The Phase I matters beyond permitting. U.S. EPA recognizes the ASTM E1527-21 standard as meeting its All Appropriate Inquiries rule, and completing those inquiries before purchase is a condition of the federal landowner liability protections if contamination turns up later.

Which state streamlining laws could apply to your site in 2026?

These newer routes can take months off an entitlement schedule:

• AB 130 infill CEQA exemption (Public Resources Code 21080.66).

  Signed June 30, 2025, and effective immediately, it exempts qualifying housing projects on sites of 20 acres or less from the California Environmental Quality Act (CEQA). The site must:

  • Be in a city or a Census-defined urban area
  • Be previously developed or mostly surrounded by urban uses
  • Match the general plan and zoning
  • Reach at least half of the default density that state housing law sets for the jurisdiction
• SB 131 "near-miss" review (Public Resources Code 21080.1). A housing project that would be exempt but for a single condition gets CEQA review limited to the effects of that one condition. Fail two conditions, or sit on natural and protected lands, and the shortcut is gone.
• SB 79 transit-oriented housing (Government Code 65912.155 to 65912.162).

  In effect since July 1, 2026, it applies in counties with more than 15 passenger rail stations; legislative analysis cited by regional planners suggests eight qualify (Alameda, Los Angeles, Orange, Sacramento, San Diego, San Francisco, San Mateo, and Santa Clara).

  It makes housing of five or more units an allowed use on residential, mixed-use, and commercial sites within a quarter mile of a qualifying rail or bus rapid transit stop (a half mile in cities of 35,000 or more), with state-set height, density, and residential floor area standards that local zoning cannot go below.

  Projects of 11 or more units must set aside at least 7% of units for extremely low income, 10% for very low income, or 13% for lower income households.

• SB 423 streamlined ministerial approval (Government Code 65913.4).

  The SB 35 by-right process, now extended to January 1, 2036, applies in cities and counties that the state Department of Housing and Community Development (HCD) finds behind on their housing targets or without a housing element in substantial compliance. HCD's 2026 determination sets whether projects there need at least 10% or 50% affordable units.

  Check HCD's live Streamlined Ministerial Approval Process (SMAP) dashboard, because a jurisdiction's status can change during the year.

• AB 2011 (Government Code 65912.100 and following). Ministerial approval for qualifying housing in zones where office, retail, or parking are a principally permitted use, available until January 1, 2033.
• Small-lot subdivisions (Government Code 66499.41). Ministerial review of maps creating 10 or fewer parcels on qualifying multifamily lots up to five acres or vacant single-family lots up to 1.5 acres. Our explainer on SB 1169 and tentative map timelines covers this path in more detail.

SB 79 does not create its own ministerial process or exempt projects from CEQA. However, Government Code 65912.159 makes SB 79 projects eligible for SB 423 ministerial approval even where HCD has not found the city subject to SB 423, and at the 10% affordability level. The project must still meet SB 423's other requirements, including its site exclusions and labor standards; otherwise it goes through the city's normal review under the Housing Accountability Act.

Why does eligibility still come down to site conditions?

Every route above is conditional, and eligibility is decided parcel by parcel. The AB 130 exemption, for example, adopts the site exclusions of SB 423 (Government Code 65913.4(a)(6)):

• Excluded:
  • Certain coastal zone areas
  • Prime farmland or farmland of statewide importance
  • Wetlands
  • Protected-species habitat
  • Land set aside in a natural community conservation plan
  • Land under a conservation easement
• Excluded unless conditions are met:
  • Very high fire hazard severity zones and any land in the State Responsibility Area (where preventing and suppressing wildfires is primarily the state's responsibility)
  • Earthquake fault zones
  • Special flood hazard areas
  • Regulatory floodways
  • Listed hazardous waste sites

  Each has its own test, such as meeting state fire and seismic building standards or holding a qualifying closure letter.

The exemption adds conditions of its own.

• The developer must complete a Phase I, and if it finds a recognized environmental condition, a preliminary endangerment assessment and any required cleanup before occupancy.
• Housing within 500 feet of a freeway needs centralized ventilation with MERV 16 filtration and no freeway-facing balconies.
• The project cannot demolish a historic structure on a national, state, or local register.

The local agency must also invite traditionally and culturally affiliated California Native American tribes to consult. Tribes have 60 days to accept, and consultation can run 45 days plus a 15-day extension. Agreed measures become binding conditions of approval. After that, the agency generally has 30 days to approve or deny the project under the Permit Streamlining Act (Government Code 65950).

AB 130 exemption: tribal consultation and decision timing

Illustrative diagram — not to scale

1. 1Accept: tribes have 60 days to accept the invitation to consult.
2. 2Consult: can run 45 days plus a 15-day extension; agreed measures become binding conditions of approval.
3. 3Decide: the agency generally has 30 days to approve or deny under the Permit Streamlining Act.

SB 79 has its own site limits. Since July 16, 2026, SB 722 bars SB 79 projects on mobilehome park and RV park sites. Sites with recently occupied rent-controlled housing face demolition restrictions.

What does skipping due diligence cost?

A buyer who assumes a parcel qualifies for a streamlined path, then learns at submittal that it sits in an excluded flood area or cannot reach the minimum density, loses the time advantage the law was meant to provide. They may also have paid a price that only works on a streamlined schedule.

Physical surprises hurt as much. Utility capacity, soils, off-site frontage improvements, and stormwater requirements can move a cost opinion enough to change whether a deal closes. Finding them early lets you remove them, price them into the purchase, or pass.

What this means for your project

If you are evaluating a California parcel, this order puts the likely deal-breakers first:

1. Title and boundaries. Review the preliminary title report and order a boundary survey or ALTA/NSPS survey early in escrow.
2. Hazards and exclusions. Check the FEMA flood zone, earthquake fault zone maps, whether the parcel is in a CAL FIRE fire hazard severity zone or the State Responsibility Area, state hazardous-site lists, and farmland and habitat mapping.
3. Approval path. Compare zoning and the general plan against the routes above. Check HCD's streamlining dashboard and your regional transit-stop maps for SB 79.
4. Utilities. Confirm water, sewer, and storm drain capacity with the service providers.
5. Cost and schedule. Build a cost opinion and timeline for each viable path, then decide.

Requirements vary by city and county, and local agencies read state law differently, so confirm eligibility with the planning department before you rely on it. Our planning and entitlement services cover that conversation. If the plan involves dividing the land, see parcel and subdivision maps.

Considering a site? Tell us about the parcel and what you hope to build, and we can talk through which investigations fit the decision in front of you.