Since the inception of the Delta Plan, farmland loss in the Sacramento-San Joaquin Delta has been limited to 3,405 acres.

The Measure

No change in farmland land use due to urban development.  

  • Expectations

    Farmland in the Delta is preserved and local government general plans maintain land designated for agricultural land use.

  • Performance Metrics

    • Conversion of farmland acres to urban development
    • General Plan land designation change from agricultural land to urban land

Farmland in the Delta

This chart shows acres of Delta and Suisun Marsh farmland lost and planned farmland loss in 2014 and 2016. The map shows location of current Delta and Suisun Marsh farmland.

2016 Land Use in the Delta and Suisun Marsh

Next Data Update: The Department of Conservation is processing remotely sensed data to update the 2018 Farmland Mapping and Monitoring Program (FMMP). 

Agriculture is the largest and most vital industry in the Delta. However, even though agriculture is the principle land use in the Delta, the total area of farmland has declined by about 20,000 acres during the last 30 years (DOC, 2015).

Under current local government general plans, substantial farmland will change to urban development, resulting in up to 28,000 acres of additional lost farmland (Delta Plan, 2013). Reductions in the Delta farmland will impact businesses, jobs, and communities because cultivated farmland is critical to the Delta’s significant agricultural economy. Preserving farmland promotes community and small family farms and retains the Delta’s rural heritage. This measure tracks how much farmland is being converted to urban land and how much is planned for conversion.

Each chapter of the Delta plan includes strategies to achieve the goals of the plan. These strategies are general guidance on achieving the objective laid out in the plan and in the Delta Reform Act of 2009. Associated with these strategies are recommendations. The recommendations describe more specific and implementable actions to support the achievement of Delta Plan strategies. Strategies may also have associated performance measures. Delta Plan performance measures track progress in achieving desired outcomes for the Delta Plan. Below are the strategies and recommendations associated with this performance measure. 

Delta Plan Strategies
  • Maintain Delta Agriculture
  • Plan to Protect the Delta’s Lands and Communities
Delta Plan Recommendations
  • Promote Value-added Crop Processing
  • Encourage Agritourism
  • Encourage Wildlife-friendly Farming
  • Plan for the Vitality and Preservation of Legacy Communities
  • Buy Rights of Way from Willing Sellers When Feasible
  • Provide Adequate Infrastructure
  • Plan for State Highways
  • Subsidence Reduction and Reversal

To be evaluated annually:

  • Conversion of farmland acres to urban development, evaluated in conjunction with updates to the Farmland Mapping and Monitoring Program.
  • Conversion of land designated for agricultural use to urban land use, under General Plan land designations, evaluated annually.

Number of acres of Delta farmland designated for agriculture in Delta Plan regulations at the time of Delta Plan adoption in May of 2013.


By 2025, no conversion of farmland to urban development as defined by Delta Plan regulations.

Data Source

The Farmland Mapping and Monitoring Program (FMMP) from the Department of Conservation


For every year, the Delta counties data was downloaded from the FMMP FTP.  The county shapefiles were merged, then clipped to the legal Delta and Suisun Marsh using arcGIS. The areas were calculated for each polygon. Then the areas were summed by category.

The area of all the agricultural categories was summed. Data in the following categories were included to calculate the amount of agricultural land:

  • Confined Animal Agriculture
  • Grazing Land
  • Farmland of Local Importance
  • Farmland of Local Potential
  • Prime Farmland
  • Farmland of Statewide Importance
  • Semi-Agricultural and Rural Commercial Land
  • Unique Farmland

Using the 556,477 acres of farmland in the 2012 FMMP for the legal Delta and Suisun Marsh the difference between 2012 and each of 2014 and 2016 was calculated.  That difference is reported as the cumulative loss of farmland in the legal Delta and Suisun Marsh.

Have questions or comments about this measure? Contact Us