Parsons Slough is a 450-acre complex of mudflats and other tidal wetlands. This area historically supported 400 acres of tidal marsh, but now only 35 acres remain. In the first half of the twentieth century the area was diked off from the tides and drained for farming. The marsh soils dried and shrunk, lowering the land surface in a process called subsidence.

In late 1982, shortly after the land was acquired by the California Department of Fish and Game, the dikes around Parsons Slough broke. When the tides returned, currents, tidal scour and marsh loss accelerated throughout Elkhorn Slough.

Parsons Slough makes up 15 percent of Elkhorn Slough by land area, but because of subsidence it accounts for 35 percent of the daily exchange of tidal waters by volume. Powerful currents now prevent the establishment of salt marsh in Parsons Slough and contribute to tidal scour and the die back of salt marsh in the rest of the estuary.

Reducing tidal exchange at Parsons Slough would slow currents in many parts of Elkhorn Slough, increasing the viability of salt marsh and soft mud habitats throughout the estuary. Salt marsh can also be restored in Parsons Slough by adding sediment to raise the elevation of subsided former marshes.

The Parsons Slough planning process is evaluating how these strategies can be implemented to preserve Elkhorn Slough salt marshes and soft mud habitats while protecting the high quality existing habitat in Parsons Slough for sharks and rays, sea otters, seals and shorebirds.

We welcome your insights and contributions to the process.

Parsons Slough Project Update (6-3-09, 105KB, .pdf)

Parsons Slough Wetland Restoration Plan

We invite you to download the documents and provide comments. Each comment should identify the specific document title, page and line number associated with the comment. If the comment is more general, feel free to just use the word 'general'. Comments are now being accepted.

Parsons Slough Adjustable Sill Concept Modeling (.doc, 2.18MB)

There are five draft documents:
Draft Executive Summary (65KB .pdf)
Draft Existing Conditions Report (3.24MB .pdf)
Draft Sediment Additions Report (2.37MB .pdf)
Draft Alternatives Analysis Report (5.02MB .pdf)
Draft Restoration Plan (3.31MB .pdf)

These are also bundled together into a file called
Draft Final Report: Parsons Slough Restoration Plan (15.13MB .pdf)

The Tidal Wetland Project hosted a series of meetings on Dec. 2, 2008 to advance the Parsons Slough Restoration Project. Notes, presentations and comment forms from these meetings are available by clicking below:

Parsons Slough Restoration Team meeting notes (70KB .pdf)
JOINT Science Panel and Strategic Planning Team meeting notes (52KB .doc)
Parsons Slough Restoration Project Public Meeting notes (37KB .doc)
Parsons Slough Project presentation (Bryan Largay, ESNERR) (3.54MB .pdf)
Parsons Slough Draft Restoration Plan presentation part 1 (Chris Webb, Moffatt & Nichol) 1.7MB .pdf
Parsons Slough Draft Restoration Plan presentation part 2 (Chris Webb, Moffatt & Nichol) 2.1MB .pdf
Parsons Slough comments sheet (116KB .pdf)

We welcome your questions and comments.

The State Coastal Conservancy (SCC), working closely with the Elkhorn Slough Reserve and Elkhorn Slough Foundation, has hired a consulting team led by Moffatt & Nichol to provide consulting services to develop a Parsons Slough Wetland Restoration Plan. The Plan will evaluate tidal marsh restoration alternatives for Parsons Slough including actions to reduce the tidal prism in the area and/or add sediment to rebuild marsh elevations.  This Plan is part of the Elkhorn Slough Tidal Wetland Project.
Additional details about the project scope can be found in the Request for Services (.pdf 597KB), in the Project Work Program (.doc 65KB), and in the Project Goals and Objectives (.doc 51KB).

2005 Aerial Photo of Parsons Slough

Parsons Restoration Team (PRT)  Current Participants:

Parsons Slough Restoration Planning Consultant Team Leads: