In 1998, California Department of Fish and Game
(CDFG) acquired the Merced River Ranch (MRR) with the goals of protecting riparian habitat, improving
conditions for salmonids, and providing a long-term source for spawning gravel for the Merced River
and nearby projects (CDFG 1998). Restoration planning began with Phase I of the
Merced River Corridor Restoration Plan,
funded by U.S. Fish and Wildlife Service's Anadromous
Fish Restoration Program (AFRP). The primary goal of Phase I was to provide a technically sound,
publicly supported and feasible plan to restore habitat for fish populations in the lower 52 mi (84 km)
of the Merced River. The plan extent is from Crocker-Huffman Dam to the confluence with the San Joaquin
River, and includes the Dredger Tailings Reach (DTR) in which MRR is contained.
Phase II of the process was funded by CALFED in
1998, and consisted of baseline investigations into the geomorphic and riparian vegetation characteristics
of the project reach (Stillwater Sciences 2001).
These investigations include the DTR and also identify social, institutional, and infrastructural
opportunities and constraints for restoration (Stillwater Sciences and EDAW 2001). In 2000, CALFED
funded Phase III that included the development of the Merced River Corridor Restoration Plan (Stillwater
Sciences 2002) and a series of public workshops to present the plan and receive input from interested
stakeholders and the public.
The Restoration Plan identifies objectives and actions based on the scientific understanding of
the Merced River. To guide restoration planning and address the various environmental impacts
in the DTR, the Plan identified the following specific restoration objectives:
- Balance sediment supply and transport capacity to allow the accumulation and retention of salmonid spawning gravel;
- Restore floodplain functions that foster recruitment of riparian vegetation and the quality of riparian habitat;
- Increase in-channel habitat complexity to improve aquatic habitat for native aquatic species; and
- Re-engineer the low-flow and bankfull channel geometry so that it is scaled to function properly under current (regulated) flow conditions and to prevent riparian vegetation encroachment in the active channel.
From 2003 to 2006, Phase IV of the planning process built upon the Phase III plan with funding from the
California Bay-Delta Authority. The Phase IV objective was to design pilot floodplain and channel
restoration experiments at MRR to initiate the restoration of natural ecosystem function, and to
develop monitoring and evaluation plans to improve scientific understanding of the driving processes
for floodplain restoration and inform future projects. Studies on tailings volume and texture, potential
for mercury contamination, wetlands extent, revegetation, biological conditions, and hydrology were
completed and served as the foundation for implementation of the restoration project.
In Phase V of the project, Cramer Fish Sciences (CFS) worked with Philip Williams and Associates
(PWA) to complete a revised project design plan and implement the project with AFRP and in coordination
with the CDFG. Cramer Fish Sciences completed regulatory compliance, developed a restoration monitoring
program, conducted pre-project monitoring, and implemented the first and second year of project construction.
To restore (i.e., rehabilitate and enhance) channel, floodplain and riparian ecosystem
processes and critical habitats for juvenile and adult salmonids, in coordination with
local communities and stakeholders, to promote the recovery of healthy and diverse
Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O.mykiss)
populations in the Merced River, while helping to meet
the abundance goals of the Anadromous Fish Restoration Program.
- To serve as an example of publicly supported applied fisheries and restoration science;
- To augment, rehabilitate and enhance productive juvenile salmonid rearing and adult spawning habitat in the Merced River; and
- To determine project success with an efficient and scientifically robust monitoring program.
Our monitoring program will address questions regarding project implementation activities
(i.e., does the implementation match the design?), effectiveness (i.e., did the project
recover conditions suitable for salmonid rearing and spawning?), and validation of project
actions (i.e., was productive habitat for salmonids and native riparian vegetation created
by the project?). Monitoring activities include topography/bathymetry surveys, monitoring
flow and flooding inundation, physical conditions (i.e., temperature, dissolved oxygen,
turbidity), biological conditions (i.e., fish use, macroinvertebrate abundance and composition,
fish diets and growth potential), among other evaluations. These evaluations may improve our
understanding of restored ecosystem function at the Merced River Ranch and the potential
of side channel and floodplain river restoration projects to contribute to improved salmonid
PARTNERING WITH AFRP AND THE COMMUNITY
This project has been developed in coordination with the local community, and the monitoring
program was specifically designed to occur with the contribution of AFRP staff and
potentially interested community members. There are opportunities to assist with
periodic data collections including aquatic habitat sampling, vegetation and topographic
surveys, and we anticipate engaging community members and local students (from grade school
to graduate school) in contributing to the restoration and monitoring work. Through a
coordinated effort, more detailed monitoring can be accomplished and community partnerships
In 2010, the first year of implementation began for the MRR Floodplain Restoration Project.
Cramer Fish Sciences and PWA completed engineered designs in February 2010. Cramer Fish
Sciences worked with AFRP and CDFG to complete all county, state and federal permitting
processes before September 2010. Ford Construction (subcontractor) began equipment delivery
to the project site and construction began on September 23, 2010, and continued through
October 15, 2010. Instream construction began during the afternoon of September 28, 2010,
and continued through the afternoon of October 15, 2010. All heavy equipment was steam-cleaned
and dried prior to onsite delivery. Additionally, rubber-tired front-end loaders used for
instream construction were filled with biodegradable vegetable oil. Copies of project permits
were available in each vehicle and piece of heavy equipment located onsite, and all active
construction personnel were trained in permitting and monitoring requirements. The subcontractor
held regular onsite meetings to ensure all personnel understood safety requirements and
EXTEC E7 screening plant was used to process dredger tailings excavated by a CAT 320
excavator. Material was sorted into three distinct piles: (1) fines (< 5 mm); (2)
spawning gravel (5-127 mm); and (3) oversized fill (> 127 mm). Total material excavated was
~15,340 yds3, with ~12,272 yds3 of spawning gravel. Total spawning gravel
placed in the Merced River was ~10,772 yds3. At least one CFS biologist was present
during all construction activities to guide construction activities following design
criteria. The biologist also provided monitoring for the presence of spawning fall-run
Chinook salmon with visual spawning surveys conducted
twice daily at known spawning riffles adjacent to the 2010 work area. All additional
monitoring needed to meet permit requirements was conducted throughout active construction,
September 23, 2010, through October 15, 2010.
In 2011, construction and monitoring continued for the MRR restoration project. The start date
was August 29, 2011 and work continued to October 15, 2011. Further work on excavation of the
floodplain occurred with 87,222 yd3 (66,686 m3) excavated and processed. There was 19,746 yd3
(15,096 m3) of spawning gravel placed in the Merced River. Additionally, excavation continued
on the south side channel. Monitoring activities were ongoing during all construction activities
and included pre-project surveys for listed species, vegetation buffering where needed, ongoing
visual monitoring for early spawners, tracking water quality in terms of temperature and turbidity,
and determining mercury levels in excavated sediments and water. Effectiveness monitoring continued
to track macroinvertebrate abundance and composition at gravel augmentation sites, juvenile
salmonid use of augmented areas, and continuous tracking of temperature, inundation, and groundwater
In 2012, construction and monitoring will continue for the MRR restoration project. The anticipated start
date is August 1, 2012. Based on 2011 operations and currently available funding, we estimate placing
approximately 10,100 yd3 (7,722 m3) of spawning gravel within the Merced
River channel in 2012. The remaining excavation of the south-side channel will also be completed this
year. Monitoring activities will be ongoing during all construction activities and will include pre-project
surveys for listed species, vegetation buffering where needed, ongoing visual monitoring for early
spawners, tracking water quality in terms of temperature and turbidity, and determining mercury levels
in excavated sediments and water. Additionally, restoration monitoring will be ongoing to determine
the project's effectiveness at recovering conditions suitable for juvenile salmonid spawning and rearing.
When construction is completed future restoration monitoring work will track the productivity and
performance of the site, and evaluate the potential for improvement in Merced River Chinook salmon
and steelhead populations.
- Stillwater Sciences. 2001. Merced River corridor restoration plan baseline studies volume II: geomorphic and riparian vegetation investigations report. Prepared for CALFED, Sacramento, CA. 76 pp.
- Stillwater Sciences and EDAW, Inc. 2001. Merced River corridor restoration plan, identification of social, institutional, and infrastrucutral opportunities and constraints. Stillwater Sciences, Berkeley, CA. and EDAW, Inc., San Francisco, CA.
- Stillwater Sciences. 2002. Merced River Corridor Restoration Plan. Stillwater Sciences, Berkeley, California. 245 pp.