San Elijo Lagoon Mouth Opening

Last week, dredging of the San Elijo Lagoon mouth began in an effort to increase the tidal flow from the ocean. Overtime, sediment from the 77 square mile watershed collects in the lagoon and lagoon mouth, so periodic dredging is required to maintain a balance of fresh and salt water. The mouth is dredged once every few years.


Image 1: panorama of lagoon mouth at Highway 101 (click for larger image)

The process to dredge the lagoon mouth is very involved and requires heavy machinery. The tidal flow is stopped for several days by plugging up the lagoon with sand so the flow of water won’t interrupt construction. This means that the lagoon isn’t being flushed with salt water twice a day by the high tides, so the health of the estuary is compromised during this process. However, the sand removal only takes a few days so this project will enhance the health of the lagoon in the long run.



Image 2: barrier created so the equipment can move the dirt.




Image 3: Heavy equipment used to move sand and sediment.



Image 4: The sand is placed on the beach to be distributed by the waves.



Image 5: Lagoon mouth plugged up on east side of 101.

Solar Tree Parking Garage Installations at UCSD

As a part of UCSD’s sustainability initiative, Solar Trees designed by Envision Solar have been installed on top of two parking garages on campus. According to Envision, each of the Solar Trees, which use Kyocera photovoltaic modules, will generate "17,000 hours of clean energy per year, which is enough to power more than four single-family homes," which equates to 13.2 metric tons of carbon emissions per year.


Image 1: Panels placed atop parking garage near Rimac Arena, UCSD

These solar trees are big enough and are placed to provide convenient shade to park in. They have one central trunk and have 4 ‘limbs’, which support the solar panel plane. They were developed by Envision Solar with a partnership through Kyocera for a prototype parking lot in Kearny Mesa in an effort to make San Diego a leading region for Solar Power and green energy. These installations at UCSD are the most recent use of the prototype.

In 2008 UCSD adopted a new Environment and Sustainability Initiative with the goal of becoming the greenest university in the US. Photovaultaic panels installed on most campus roofs, other forms of clean energy such as wind and biogas fuel cells will soon create 7.4 megawatts of electricy which is approximately 10 – 15% of it’s annual energy use.

Three partners are working with the university on the solar photovoltaic project. Borrego Solar, Inc., a national solar power contractor based in El Cajon, Calif., is the installer; Envision Solar, Inc., of San Diego, designer of the solar “trees” that will be built on top of UC San Diego parking structures, also is involved. Solar Power Partners (SPP™), Inc., of Mill Valley, Calif., is the financier and owner of the solar photovoltaic arrays.


Image 2: cross section of tree with cars parked under.... too bad it is cloudy today



Image 3: view from above parking lot . (photo credit)