Thursday, September 27, 2018

Hidden costs of Matilija Dam


A headline in the Ventura County Star states:


Thousands of residents live in homes protected by a levee that stretches 2.65 miles along the Ventura River, between the Pacific Ocean and Shell Road.

In the more than 3,500 residential, commercial and industrial structures lie an estimated $2.157 billion worth of infrastructure and property, according to studies prepared for the Ventura County government.


Experts with the U.S. Army Corps of Engineers say that without rehabilitation, it’s likely the levee could in time breach or collapse entirely. 

When the initial levee was built in 1948, one thing not considered was the loss of sediment likely to result from construction of Matilija Dam, which had been installed on a major tributary only the year before, the corps noted.

“Basically, the foundation of the levee is higher than the potential bottom of the river,” said Paul Jenkin, Ventura County campaign coordinator for the Surfrider Foundation.

That means in a flood or high-rain event, the river could flow under the base of the levee, causing it to fail. The change has been notable. Initially, the levee was made with 8 feet of toedown, which means rocks extended that far below where the riverbed meets the base of the levee. Today, there is “minimal to no toedown protection,” the corps noted.

Poorly understood at the time, these are the long-term costs of a sediment starved river.

Although the $25 million Ventura River Levee VR-1 project is not included apart of the Matilija Dam ecosystem restoration project, 3 other levees are.  The bulk of the planning and removal costs of dam removal involve the replacement, upgrade, or new downstream infrastructure to accommodate the return of the Ventura River's natural sediment transport.


Wednesday, August 29, 2018

Ventura Hilton Hotel




The City of Ventura has circulated notice of an MND (Mitigated Negative Declaration) for the hotel project on the corner of Figueroa and the Shoreline Drive across from the fairgrounds entrance at Surfers' Point.  Originally Embassy Suites, this is now a Hilton hotel.


Surfrider commented on this in 2009 when it was first proposed, with the primary concern that this new hotel would rely on city infrastructure (promenade seawall) that the city could not afford to maintain.  The past document did not account for sea level rise, which is required under CEQA (California Environmental Quality Act)

The current document is quite thorough on the future risk of sea level rise.  For example it states:

During a 100-year storm event, waves running up through the Park could enter the first floor of the hotel, potentially breaking through the south facing doors and windows, damaging facilities and potentially endangering hotel guests and workers. Even under current climatic conditions, this type of damage is not unprecedented; for example, recent damage to the Ventura Promenade immediately upcoast where the Promenade was undercut, and planters and seat walls were destroyed by wave attack during the severe 2015-2016 El NiƱo, requiring emergency rock revetment installation.

The document further states that:

the first-floor uses are limited to retail, parking, restaurant, lobby, and meeting rooms, not hotel rooms for overnight occupation, which may be subject to coastal flooding damage and threats to life and property. As discussed further below, future conditions under increased sea level conditions may exacerbate coastal flooding and wave run-up impacts. Mitigation measures identified below would reduce the risk of structural damage, injury, or death associated with 100-year storm events, making impacts less than significant with mitigation.

Suggested mitigation for this scenario include structural reinforcement, elevation of utilities, and worker evacuation training.

In 2009 Surfrider commented that the City collect fees on coastal development to ensure funding to maintain and repair the promenade and seawall into the future.  This planned beachfront development is entirely dependent upon Ventura's aging infrastructure for protection from future storm events.

The project includes realignment and improvement of Promenade Park:




The MND is downloadable here:
https://www.cityofventura.ca.gov/DocumentCenter/View/13496/Hilton-Draft-MND-8-16-18

Earlier comments are on this blog here.

California Climate Change Assessment

On August 27, 2018, the California Natural Resources Agency released California’s Fourth Climate Change Assessment.  The goal of these assessments is to "provide the scientific foundation for understanding climate-related vulnerability at the local scale and informing resilience actions. The Climate Change Assessments directly inform State policies, plans, programs, and guidance to promote effective and integrated action to safeguard California from climate change."

The Key Findings summarize the impacts on people, infrastructure, and natural systems, and "provides critical information that will enable more ambitious efforts to support a climate-resilient California."

The Fourth Assessment included a Coast and Ocean Summary Report for the first time; this report synthesizes the latest research... about the challenges facing our coast and ocean because of climate change and what actions we can take to increase their resilience.




The Fourth Assessment study found that sea-level rise has become the dominant concern for coastal managers, and most also face funding and financing barriers.



According to the LA Times,

"At Surfers Point in Ventura County, officials turned an eroding parking lot and collapsing bike path into a cobble beach backed by vegetated dune. It has fended off erosion, widened the beach and become the most visited beach in Ventura County, the report said. During high wave conditions in the winter of 2015-16, no damage occurred at the project site: Wave run-up reached the bike path only where dunes were absent.

Other parts of the local shorelines were not so lucky: Ventura Pier was damaged in the storm and the Pierpoint neighborhood suffered inundation, the report said."
                                      
This was documented on this blog: Surfers Point - first real test



More information:

California Natural Resources Agency; http://resources.ca.gov/climate/safeguarding/research/

Climate Assessment; http://www.climateassessment.ca.gov

In the news:  Climate change will be deadlier, more destructive and costlier for California than previously believed, state warns, LA Times, Aug 27, 2018


Thursday, August 9, 2018

Mandalay Power Plant and Channel Islands Harbor



After a long series of studies and meetings, the Mandalay power plant is being removed from the Ventura County coast.   After more than 50 years of operation,  State policy now requires elimination of the plant's outdated "once though cooling" system to prevent impacts to marine life.  Energy company NRG sought to build a new plant in it's place.  The City of Oxnard and local stakeholders strongly opposed reconstruction of a new gas fired power plant, citing the impacts of air pollution on  downwind disadvantaged communities.  As the California Public Utilities Commission reviewed the application, the LA Times reported that the State was grappling with an excess of renewable solar energy. Other studies illuminated the vulnerability of the coastal site to future flooding. 

So when it seemed that the California Public Utilities Commission was not going to approve the new facility, and SCE did not renew a contract to buy the energy, the current company NRG and its subsidiary GenOn said the three facilities at the Mandalay Generating Station will cease operations by Dec. 31, 2017.

For decades the power plant pumped water from the "Edison Canal" and Channel Islands Harbor, discharging onto the beach.  Although cessation of this pumping will greatly benefit ocean waters, one potentially unintended consequence will be reduced circulation in the backwaters of the harbor.

During the heatwave in July, harbor residents noticed degraded water quality, and sounded the alarm. Meetings were held, and the City of Oxnard began testing the water and installing aeration systems to combat low dissolved oxygen.

Although cessation of the pumps may have played a role in this, water quality has been a long-standing problem in this and other harbors along the California coast.   Kiddie Beach remains impaired, and past studies concluded that lack of circulation in the harbor, harbor boating practices, and sewage contamination contribute to unhealthful bacteria levels near the mouth of the harbor.  

Mandalay Power Plant and Channel Islands Harbor
 Power plant pumps ceased in March, 2018
Poor circulation exacerbates this problem in the back channels of the harbor.   It is not surprising that recent testing identified problems in the Westport, Harbor Island, and SeaBridge areas.  In fact, Surfrider filed comments on the the SeaBridge development project when the City of Oxnard circulated an environmental document on harbor expansion.  At the time it was clear that this would create the backwater condition that has finally come to light.    

It should be noted that this is not a unique problem, and harbors throughout California frequently experience fish kills due to lowered dissolved oxygen levels.  This is usually the result of algae blooms fueled by high nutrient input combined with warm water and poor circulation.  Recent examples include Marina Del Rey (2014) and Ventura Harbor (2011).

In August 2018, Surfrider wrote a letter to the neighborhood council, and filed comments with the Regional Water Quality Control Board supporting cancellation of the Mandalay NPDES discharge permit. 

Sources of pollutants entering the harbor should be monitored and solutions developed to curtail or eliminate them.  Current water quality rules encourage improved water management practices, but until a community demands it, enforcement alone cannot force the necessary changes.  

In the meantime, the aeration systems installed by the City of Oxnard have demonstrated viability as a means to mitigate for lowered dissolved oxygen levels.  Similar to the sand-moving efforts at Oxnard Shores, this will not solve the root cause of the problem but merely help reduce the impacts of water pollution.

Surfrider commends the Channel Islands Community for uniting on this issue.  For years the poor water quality associated with the harbor has gone largely unnoticed.  The cessation of the power plant pumps may have temporarily exacerbated the problem, but the situation is not new.

We encourage the harbor residents to direct their efforts toward source control and mitigation.   Residents and boat owners can and should play a role in this process; indeed, success depends on it.

Regional Water Quality Control Board:

This item will be considered by the Regional Water Board at a public hearing, which will be held during the Board’s regularly scheduled September 13, 2018 meeting. The Board meeting will begin at 9:00 A.M. at the Ventura County Government Center Hearing Room, 800 South Victoria Avenue, Ventura, CA.

Download the Final Fact Sheet


UPDATE:

 On June 28, 2018, Regional Water Board transmitted the tentative Order which would terminate the waste discharge requirements and NPDES permit for NRG California South LP, Mandalay Generating Station located at 393 North Harbor Boulevard in Oxnard, California.  Pursuant to Division 7 of the California Water Code, the Regional Water Board, at a public hearing held on September 13, 2018, reviewed the tentative Order, considered all factors in the case, and adopted Order No. R4-2018-0130.

The Cover Letter, Termination Order No. R4-2018-0130 are posted on the web site at: https://www.waterboards.ca.gov/losangeles/board_decisions/adopted_orders/



In the news:

Jun 22, 2018 Why is the water brown at Channel Islands Harbor? 

Aug 2, 2018 Oxnard harbor water clears up as aerators debut

NRG plans to shut down Oxnard power plant earlier than expected

California invested heavily in solar power. Now there's so much that other states are sometimes paid to take it

Unseasonal heat may have triggered Marina fish kill

Thousands of dead fish scooped from Ventura Harbor


Links:

Surfrider letter to LARWCB

City of Oxnard Updates

City of Oxnard Water Testing results - arcGIS map

Channel Islands Neighborhood Council

Wishtoyo - Kiddie Beach



Wednesday, August 8, 2018

Coastal Studies for Dam Removal


The Ventura County Watershed Protection District (WPD) is finalizing a contract with a consulting team to conduct studies to assess the benefits and impacts of the removal of Matilija Dam to the Ventura River estuary and the coastline.  This study will take results from sediment transport modeling to be conducted for the dam removal project to model how this may change the estuary and coast.  Previous efforts estimated a 30% increase in coastal sediment delivery over the 50 years following dam removal.  This study will take a more detailed look at where this sediment will go and how it will affect the coastal ecosystem.

The consultant team was chosen through a selection committee convened by the Watershed Protection District to review proposals and conduct interviews.  This work is funded through a grant from the National Fish and Wildlife Foundation and is anticipated to be conducted from October 2018 through September 2019.


Conceptual model of estuarine and coastal processes, Ventura, CA (Integral Consulting Inc.)

The study area includes the Ventura River starting at the West Main Street Bridge in the City of San Buenaventura and extending south to the mouth of the river at the Pacific Ocean, thence to the nearshore coastal areas from the Emma Wood State Beach extending east to the Ventura Harbor.

Project Abstract
The modeling of sediments delivered to the Ventura River Estuary and nearshore waters is an integral component of the larger Matilija Dam removal project, which is intended to restore riverine processes to create and sustain a variety of instream, riparian, estuarine, and coastal habitats along 16 miles of the Ventura River, including the estuary and immediate nearshore waters, as well as migratory access to upstream habitats for the federally listed endangered southern California steelhead trout. A restored sediment regime will enhance habitats for a wide variety of other native species such as the federal endangered tidewater goby and federal threatened red-legged frog, as well as other state and federal endangered riparian species such as the least Bell’s vireo and southwestern willow flycatcher. Sediment delivered to the immediate nearshore inter-tidal and sub-tidal marine environment is also an important component in these coastal habitats supporting spiny lobster, brant, western snowy plover, California least tern, and legless lizard as well as a larger number of marine invertebrates (e.g., clams, mussels, anemones) and plants (surf grass, marine algae).

Modeling
Key aspects of the proposed modeling approach include:
• A lagoon model with upstream river discharge and episodic seasonal coastal exchanges through the barrier;
• An inlet model that couples the coastal model to the estuarine model and determines the conditions under which there is connectivity between the lagoon and the littoral zone;
• A coastal sediment transport model that captures littoral sediment transport processes over event timescales; and
• A shoreline model to evaluate long-term sediment transport patterns.

The coupled model will provide predictions of temporally and spatially resolved sediment transport and sedimentation within the Lagoon as well as short- and long-term predictions of shoreline change. These model outputs will then be used to assess the impacts on Lagoon and coastal habitat. 


Links:

National Fish and Wildlife Foundation

County Approves Matilija Dam Contract


Thursday, August 2, 2018

Matilija Dam Studies Begin


This week contractors began field work in the reservoir upsteam of Matilija Dam. A barge-mounted drilling rig is being used to sample the sediments trapped by the dam to update the work that was completed as part of the Corps of Engineers Feasibility Study.  Additional core samples will be collected from the dam itself, in order to assess the current state of the concrete and provide data for the structural analysis of the dam removal project.  These field studies are the first tasks in the Matilija Dam Removal 65% Planning Design Project funded by the $3.3M California Department of Fish and Wildlife Proposition 1 Grant received in May 2017.











excerpts from the contracted scope of work:

Subtask 1.1 - Geotechnical Field Investigations to Characterize Fine Sediment and Organics
...obtain and log sediment samples at six locations to an estimated depth of 60-90 feet, and perform
laboratory testing. Sampling and testing shall be performed to screen for the presence of contaminants such as heavy metals and pesticides, and the results shall be compared to earlier test findings by the US Army Corps of Engineers.
Previous investigations by the United States Army Corps of Engineers (USACE) identified that the characteristics of the organic materials in the fine sediment upstream of the dam could affect water quality during and following dam removal. Several borings were abandoned after methane gas was detected and as a result, the full depth of the sediment was not penetrated at those locations. The six borings included in the this scope of work, as indicted above, will be used to characterize the limits of the organic materials as well as collect other geotechnical information (SPT blowcount, grain size distribution and relative quantities, plasticity, shear strength, etc.) related to the sediment to confirm the transport of fine sediment from the reservoir during initial and subsequent flushing events.


Subtask 1.2 - Field Investigations to Characterize Dam Concrete
...perform concrete coring and testing to determine the appropriate material properties for use in the structural analyses
...obtain concrete cores from the downstream dam face near the two proposed orifice locations and at 4 to 6 other locations along the upstream face of the dam. The downstream cores shall be obtained from a barge platform in the plunge pool or other means of access. The upstream cores shall be obtained from the same barge platform used for the geotechnical investigations under Task 1.1.
Selected samples shall be tested for bulk specific gravity, unconfined compressive strength, splitting tensile strength, and elastic modulus properties. Petrographic analysis and gel fluorescence testing shall also be conducted to assess the presence of Alkali Silica Reaction (ASR) in the concrete.



More info:

County Approves Matilija Dam Contract

Wednesday, August 1, 2018

Grant approved for Surfers' Point

Ocean Protection Council Meeting, July 25, 2017
On July 25, 2018, the Ocean Protection Council approved a $335,000 grant for final design and engineering of Phase 2 of the Surfers’ Point Managed Shoreline Retreat project.  BEACON, the regional beach erosion agency, applied for the grant on behalf of the City of Ventura and Surfers Point Working Group.  The funding will provide for the city's consultant team to work with the Ventura County Fairgrounds and Working Group to resolve existing issues with Phase 1 of the project as well as complete planning for protection of the remaining bike path and parking lot.  



In the meantime, the City of Ventura is working to prepare a site plan in preparation for this future work.  On June 18, 2018, City Council voted unanimously to:


  • Authorize the City Manager to execute a Professional Services Agreement with RRM Design Group to provide a conceptual site plan for Surfers Point Managed Retreat, Phase 2, in the amount not-to-exceed $61,640, and authorize the encumbrance of contingency funds in the amount of $6,100 for a total encumbrance of $67,740; term of agreement: June 4, 2018 - June 4, 2019.


This  City of Ventura and BEACON will be contributing both funding ($50,000 City of Ventura) and in-kind professional and consultant services (City of Ventura and BEACON staff and consultants) equal to at least 25% of the total project budget. The Surfrider Foundation continues to contribute funding and volunteer time in ongoing dune restoration program in partnership with the city's Volunteer Ventura program.



Links:

Ocean Protection Council Meeting, July 25, 2018

Ventura City Council, Agenda and minutes, June 18, 2018

Ventura County Fairgrounds 

More on this blog:  Surfers' Point