Thursday, November 27, 2008

runoff and sewage


tried looking for surf yesterday. I normally don't even consider it after the rains, but wanted to show an out of town visitor around...

headed up the coast, hoping for cleaner water...

the oilfields were flowing hard, large brown plumes entering the ocean.

Hobson looked cleaner, surf was rideable...

the work crew on the road said "I wouldn't go out there if I were you"

sewage pipe had broken...

no signs posted on the beach. I thought this was legally required if there was a sewage spill...

I'll stick to the bike for a while...

Friday, November 21, 2008

BEACON Regional Sediment Management Plan

November 21, 2008 - public Hearing on Regional Sediment Management Plan

BEACON has just released the most comprehensive overview of the Santa Barbara/Ventura County coast to date. The Beach Erosion Authority for Clean Oceans and Nourishment (BEACON) is a California Joint Powers agency established in 1992 to address coastal erosion, beach nourishment and clean oceans within the Central California Coast from Point Conception to Point Mugu.

The study includes some interesting graphics describing the state of our coast. This image illustrates the extent of coastal armoring (seawalls, revetments, etc)


This graphic illustrates shoreline trends.
The study defines a sediment budget for the region, outlines sources and sinks of beach sand, and proposes management strategies.



Some of the proposed projects are:

  • Investigate the feasibility of beach preservation and enhancement projects at Arroyo Burro County Beach, Butterfly Beach, Summerland Beach, Santa Claus Beach, and La Conchita Beach using multi-purpose offshore reef sand retention solutions.
  • Designate the Ventura River Delta as a gravel, boulders, and cobble (GBC) sediment and nourishment maintenance zone.
  • Designate the Matilija Dam as a regional sediment source site and support removal of the dam.
  • Implement the Surfers Point Managed Retreat Project.
  • Implement the Pierpont Beach wind blown sand management project.
  • Investigate the feasibility of capturing sand for beneficial reuse just before it falls into the Mugu Submarine Canyon




The study also includes an economic analysis which makes the case for widening beaches. The study is available on the BEACON website, and comments are being accepted.

Tuesday, November 18, 2008

Matilija Dam - more slurry disposal

In preparation for the next Matilija Dam Design Oversight Group (DOG) meeting on December 4th, we have been out looking at the slurry disposal sites. The issue is summarized in notes from the last DOG meeting on October 2nd.

In our comment letter, we pointed out that one of the proposed disposal areas (MODA) is a very popular public access point, of which there are few within the watershed. We are also concerned that disposal in this area would be permanent, rather than located in an area where the river would be allowed to wash the fine sediments downstream during future floods.




An analysis of erosion potential is available at matilijadam.org: Bureau of Reclamation Hydraulic Analyses of Sediment Disposal Sites Presentation

MODA (Meiners Oaks Disposal Area) is shown in this image. The blue shading is the area which the river could potentially erode in the future during a 100-yr flood. Note that the planned levee upstream of the site would effectively prevent the river from accessing this portion of the floodplain.

This photo is taken from the bluff near the trailhead, and shows the 70 acre floodplain area. The entire 2.1 million cubic yards of sediment could be deposited here at an average height of 35 feet.






The upstream Baldwin Rd site (BRDA1) is within the floodplain. Because these are active river channels there is less old growth vegetation (oaks and sycamores) and more riparian floodplain vegetation. The analysis shows that this site would erode in the future (blue shading).

This photo shows the view looking upstream from the levee that protects a historic 'burn dump' landfill in the floodplain.














The second Baldwin Rd site (BRDA2) is County property that used to be the jail honor farm. The site includes active channel and floodplain terrace, much of which was used for grazing. The river would also erode much of this site in the future.


This is the view from the highway looking south:
This view is looking upstream from the westernmost corner of BRDA2, with the active channel visible to the right.



Discussion of slurry disposal will be continued at the December 4th DOG meeting.

Friday, November 14, 2008

'Salmon Run'



Last Sunday was the 15th Annual Salmon Run. This event has become a tradition in Ventura...


Over a dozen organizations had information tables for the over 400 runners and walkers.

Event proceeds went to the Friends of the Santa Clara River.

Thursday, November 13, 2008

Algae: problem or symptom?


The EPA has listed the Ventura River as an "impaired water body" for a variety of problems, including trash, bacteria, water diversion and pumping, and pesticides (DDT/PCBs). The Clean Water Act requires that government take action to solve the problems to ensure the river is fishable and swimable. The regulatory mechanism for this is "Total Maximum Daily Load," or TMDL.

For the past year, the State Water Quality Control Board has been working to develop a TMDL for Algae in the Ventura River. See also the County of Ventura website.

The primary concern is that algae growth may be fueled by excess nutrients (nitrate and phosphate), which in turn creates large daily swings in dissolved oxygen (DO.) If DO drops below 4 mg/l, aquatic life can become stressed and fish kills may occur. (This is also called 'eutrophication') The presence of endangered species makes this issue even more critical.

Stream Team volunteer data has been used along with scientific analysis at UCSB to monitor and study algae over the past year. This graph is actual data from 24 hours of sampling on the Ventura River. It illustrates how photosynthesizing algae releases O2 during daylight hours, generating peak DO measurements in the early afternoon. However, overnight DO levels drop dramatically, with a minimum in the pre-dawn hours.


Traditionally, nutrients are seen as the driver for excess algae growth. Nutrients may originate from broad land uses such as agriculture, livestock, septic tanks, treated wastewater, as well as atmospheric deposition. It turns out that algae is widespread throughout the Ventura River watershed, and is highly variable with season and annual climate (wet or dry year.) Algae is also dependent on river flows, water temperature, sedimentation, and a host of other variables.

Because of these complex relationships, algae may be seen as a symptom of ecological stress, rather than a problem in itself. This raises a complex question when it comes to regulating algae as a pollutant: the TMDL process was originally developed to control point-source pollution.

Recent literature points to the need for an ecosystem level approach to solving such problems. A useful reference is Water Quality: Management of a Natural Resource

It is clear that in this watershed with shallow, over-drafted aquifers and strong surface water/groundwater interactions, a meaningful algae TMDL will require a watershed approach that takes into account ecosystem processes. Integrated watershed management will be necessary to address excess algae in the Ventura River.

Here's one solution: convert all those algae forming nutrients to biodiesel

Monday, November 10, 2008

Pierpont Beach erosion in 1936


Pierpont Beach Flood 1936

Los Angeles developer Frank Meline subdivided the Pierpont Bay area into small lots during the late 1920s, putting in roads, building a pleasure pier and paving Shore Drive along the beach. The lots came with design guidelines for English-style homes, on lanes with English sounding names. The Stock Market Crash of 1929 changed the fate of Pierpont beach forever; lots that had been offered for $2900 per lot suddenly were worth $10. Then, eight years later, two storms – eleven months apart – in January and December 1936 wiped out the pier, bathhouse, boardwalk and Shore Drive. These storms effectively stopped all development in Pierpont until the mid-50s. Between 1925 and 1936, few houses had been built, and after the storm some were moved to higher ground. Only a handful of pre-1936 houses remain in Pierpont. Today, the area is a eclectic mix of mid-century beach shacks and recent 2.5-story custom homes of every style imaginable, and Shore Drive is a memory beneath the dunes at the end of the lanes.

Quoted from the 2009 Ventura Architectural Calendar "Then and Now" available in local shops or by contacting schafphoto@mac.com for prices: http://www.schafphoto.com/

Friday, November 7, 2008

San Clemente Dam removal

On Nov 5, 2008, the California Coastal Conservancy hosted a tour of the San Clemente Dam on the Carmel River near Monterey, CA. Planning is underway for the removal of this obsolete dam. Constructed in 1921, the structure has become a liability to its owner, CalAm Water, mainly due to sedimentation and structural instability.


San Clemente dam is located just downstream of the confluence of the Carmel River and San Clemente Creek, and the majority of the accumulated sediment is located along the Carmel River. This is the view looking upstream: the sediment 'wedge' is clearly visible on the left, and San Clemente Creek is to the right.


The Coastal Conservancy has taken the lead working with CalAm to investigate the potential for removing the dam. As with all dam removal projects, sediment management is the primary technical hurdle. In the case of San Clemente Dam, the geography provides an interesting opportunity to stabilize the 2.5 million cubic yards of sediment in place, and divert the river around the current reservoir. The proposed project would blast a new channel through the ridge separating the river from the creek, and divert the Carmel River into the creek approximately one-half mile upstream from the dam.

The rock blasted from the bypass channel would be used to create a structure (the “diversion dike”) which would force the river into the diversion. The bypassed portion of the Carmel River would be used as a sediment disposal site for the accumulated sediment. Sediment would be removed from behind the dam to the bypassed portion of the reservoir over one season by excavation with heavy earthmoving equipment. Approximately 380,000 cubic yards of sediment in the San Clemente Creek arm of the reservoir would be relocated to the Carmel River arm, where the bulk of accumulated sediment already has been deposited. The sediments at the downstream end of the bypassed reservoir arm would be stabilized and protected from erosion. The San Clemente Creek channel would be reconstructed through its historic inundation zone from the exit of the diversion channel to the dam site.

Project Benefits:
  • 25 miles of spawning and rearing habitat for steelhead trout
  • restoring the natural sediment supply to the downstream beaches
  • providing new recreation opportunities for the public
Cost estimate: $83 million

CAW would pay an amount equivalent to the cost of buttressing the dam in place, which was estimated in 2005 as $49 million. The State and Federal government, through the leadership of the Conservancy and NOAA Fisheries, would secure the additional funds needed from State, Federal and private foundation sources.

Sediment Management: Stabilize on-site

More Information: http://www.scc.ca.gov/disp_gen.file?san_clemente

Project Manager Trish Chapman: tchapman@scc.ca.gov or (510) 286-0749

The EIR is here: http://www.sjd.water.ca.gov/environmentalservices/sanclemente/index.cfm

Tuesday, November 4, 2008

Matilija Coalition comments on Matilija Dam Project





Matilija Coalition comment letters on the final design components of the Matilija Dam Ecosystem Restoration project are now online on the www.matilija-coalition.org website

As always, the most recent information is on this blog

First Flush


Sanjon Rd, bottom of the urban watershed