Hill Slough Tidal Habitat Restoration

Status Planning County Solano
Project Type Compensatory mitigation Location 38.22920° N, -121.99814° W Map
Project Area (Acres) 1,651 Last Updated 18 July 2024
Project Abstract The project aims to restore tidal wetlands and moist grassland habitat as well as reintroduce tidal action to the site. This project satisfies mitigation as part of a settlement from a 2004 Kinder Morgan pipeline spill, as well as tidal marsh acreage goals for the 2014 Suisun Marsh Management Plan.
Project Groups DeltaView | EcoRestore | San Francisco Bay Adaptation
Administrative Region San Francisco Bay Regional Water Quality Control Board - Xavier Fernandez, SFBRWQCB

Project Identification

ERP-07D-P03 CALFED - Project ID
7208186 CALFED - Site ID
DFW_209 DeltaView - Project ID
394897 SWRCB - 401 Certification Letter (e.g., Site Number or WDID)
792572 SWRCB - CIWQS Place Number
1982038 (HSWA) WCB - Project ID
1986066 (HSWA) WCB - Project ID
1976008 (HSTHR) WCB - Project ID
1977020 (HSTHR) WCB - Project ID
1981037 (HSWA) WCB - Project ID

Habitat Plan

Site NamePhaseActivitySubActivitiesHabitatSubHabitatAcresActivity StatusWater Regime
Hill Slough Tidal Habitat Restoration None Restoration/Rehabilitation Wildlife-specific Measures Estuarine Wetland Emergent Saline to Brackish Marsh 649.0 Construction planned Fully tidal
Hill Slough Tidal Habitat Restoration None Enhancement Water Management Seasonal Wetland Diked wetland 192.0 Construction planned Managed non-tidal
Hill Slough Tidal Habitat Restoration None Acquisition/Preservation/Protection Fee Title Unknown/unspecified habitat None 940.0 Completed
Hill Slough Tidal Habitat Restoration - Project Boundary None Restoration (unspecified) Estuarine Wetland Marsh 845.4 Construction planned
Hill Slough Wildlife Area None Acquisition/Preservation/Protection Fee Title Unknown/unspecified habitat None 810.0 Completed

Related Habitat Impacts

Impact Project NameHabitatAcres LostType of Loss
No Data


Hill Slough Tidal Habitat Restoration Construction in-progress 1,781
Hill Slough Tidal Habitat Restoration - Project Boundary Construction planned 845.4
Hill Slough Wildlife Area Completed 810.0


DateTypeDescriptionSite Name
2008-06-15 Project start date


Partner Aaron Will Ducks Unlimited, Inc. Delta and Suisun Marsh Program
Partner Sarah Estrella California Department of Fish and Wildlife Not applicable/Unknown
Agency Staff Armin Halston USFWS - U.S. Fish and Wildlife Service Not applicable/Unknown


None Restoration/Rehabilitation CDFW California Department of Fish and Wildlife $9,300,000
None Acquisition/Preservation/Protection WCB Land Acquisition Program $1,769,350
None Restoration/Rehabilitation CDWR California Department of Water Resources $700,000
None Restoration/Rehabilitation CDFW Ecosystem Restoration Program $646,642

Related CRAM Assessments

Visit DateVersionSite NameWetland TypeIndex Score
2022-11-01 6.1 NWCA 21 - 10030 estuarine perennial non-saline 58

Performance Criteria

StatusDetailsEvaluation Date
Original criteria ER R2-01 Prioritize and Implement Projects that Restore Delta Habitat 2008-06-15
Original criteria ER P2-01 Restore Habitats at Appropriate Elevations 2008-06-15
Name File Type Submitted On Submitted By
Hill Slough Tidal Marsh powerpoint Other 2020-05-21 Kelly Iknayan, San Francisco Estuary Institute

How to Use the Habitat Development Curve

Habitat Development Curves (HDCs) are used to determine the developmental status and trajectory of on-the-ground projects to create, restore, or enhance California wetland and stream habitats. Each HDC is based on assessments of habitat condition for different age areas of one habitat type that in aggregate represent the full spectrum of habitat development. The assessments of condition are provided by expert applications of the California Rapid Assessment Method (CRAM). Visit the CRAM website for more information about CRAM.

For each HDC, reference condition is represented by areas of a habitat that consistently get very high CRAM scores, have not been subject to disruptive management practices, and exist within landscapes that are protected and managed for their natural conditions. The horizontal lines intersecting the top of an HDC represent the mean CRAM score and standard deviation of scores for 25 qualifying reference areas.

The age of a project is estimated as the elapsed time in years between the groundwork end date for the project and the date of the CRAM assessment. To add or update a groundwork end date, use the Project Events form in Project Tracker (ptrack.ecoatlas.org). The minimum age in years of a non-project area, including any natural reference area, is estimated from all available local information, including historical maps and imagery, historical written accounts, and place-specific scientific studies of habitat development.

An HDC can be used to address the following questions:

  1. At what time in the future will the area of assessed habitat achieve the reference condition or other milestones in habitat development? The HDC can answer this question if the CRAM score for the assessed area is within the confidence interval of the HDC. The answer is the time in years along the HDC between the current age of the assessed area and the future date corresponding to the intersection of the HDC and the reference condition or other milestone.
  2. Is the area of assessed habitat likely to develop faster, slower, or at the same pace as most other areas of the same habitat type? The habitat area is likely to develop faster, slower, or at the same pace if the CRAM score for the area is above, below, or within the confidence interval of the HDC, respectively.
  3. What can be done to improve the condition of the habitat area or to increase its rate of development? HDCs by themselves cannot answer this question. Possible answers can be inferred by the following analysis that involves HDCs:
    1. Examine the HDC for each of the four CRAM Attributes;
    2. Identify the Attribute(s) scoring below the HDC;
    3. For any low-scoring Attribute, examine the component Metric Scores (note: the Metric Scores for any public CRAM assessment in the CRAM database can be obtained through EcoAtlas);
    4. Assume the low score of an Attribute is due to its low-scoring Metric(s);
    5. Consider modifying the design or management of the habitat area in ways that will sustainably increase its score(s) for the low-scoring Metric(s).

For more information about CRAM Attributes and Metrics, including their scientific rationale, see the CRAM Manual.

Display Habitat Development Curves For Wetland Type:

CRAM Site Scores