Dixon Mine Road Bridge Replacement Project

Status Planning County Alpine
Project Type Repair/Maintenance Location 38.60065° N, -119.68892° W Map
Project Area (Acres) No Data Last Updated 3 November 2020
Project Abstract The purpose of the Project is to replace the functionally obsolete and structurally damaged bridge which crosses Wolf Creek along Dixon Mine Road. A new bridge is needed to maintain safe and reasonable access for all classes of private and official vehicles ranging from passenger vehicles to fully loaded semi-trucks and trailers.

Project Identification

31C-0002 Caltrans - Record Number
1600-2016-0114-R2 CDFW - 1600 Series Permit
6A021605003 SWRCB - 401 Certification Letter (e.g., Site Number or WDID)
SPK-2016-00365 USACE - Nationwide General Permit

Habitat Plan

ActivitySubActivitiesHabitatSubHabitatAcresActivity StatusWater Regime
Repair/Maintenance Road, Bridge, Culvert Repair and Replacement Riverine Wetland Channel < 0.1 Construction planned Perennial non-tidal
Repair/Maintenance Riverine Wetland Riparian area < 0.1 Construction planned
Repair/Maintenance Road, Bridge, Culvert Repair and Replacement Seasonal Wetland Grassland and associated wetland < 0.1 Construction planned
Repair/Maintenance Upland Forested 0.17 Construction planned

Related Habitat Impacts

HabitatAcres LostType of Loss
No Data


No Data


DateTypeDescriptionSite Name
2019-10-15 Project end date
2019-10-15 Groundwork end Dixon Mine Road Bridge Replacement Project
2019-07-15 Project start date
2019-07-15 Groundwork start Dixon Mine Road Bridge Replacement Project
2017-09-27 Permit Section 404 permit under NWP 14 obtained by U.S. Army Corps of Engineers.
2017-08-09 Permit Section 401 Water Quality Certification approved by Lahontan Regional Water Quality Control Board.
2015-04-01 Report Biological Assessment prepared.
2013-11-01 Report Delineation of Waters of the United States prepared by North State Resources, Inc.


Agency Staff Patty Z. Kouyoumdjian Lahontan Regional Water Quality Control Board Not applicable/Unknown
Agency Staff Brian Peters Alpine County Not applicable/Unknown
Partner Rita Wilke Panorama Environmental Not applicable/Unknown
Contact Leland Mason Quincy Engineering, Inc. Not applicable/Unknown


No Data

Related CRAM Assessments

Visit DateVersionSite NameWetland TypeIndex Score
No Data

No files found.

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