Just Why Is Mission Bay Being Dredged?

A project to dredge sections of Mission Bay began last week by the City of San Diego. A large crane mounted on a barge has begun to excavate about a total of 64 acres of the bay as part of the plan.

Why is the Bay being dredged?

It’s all about the boats. Apparently over the last 50 years storms and currents – as well as boats themselves – have moved the floor of the Bay around and now it’s uneven and unsafe for boating. The dredging will make it easier and safer for boats to navigate around the Bay, the largest aquatic park on the West Coast.

As the material on the bay floor is pulled up by the crane, it’s deposited onto boats, which then transport the sand, mud and organic material to a designated reuse area. From there it will be deposited back to the bottom of the bay. A majority of the extracted material will be placed at various other locations in the bay, and the remaining materials will be used to restore beaches along Crown Point and Vacation Island.

To mitigate potential impacts to marine wildlife, up to 70 acres of eelgrass will be replanted in various locations using a team of scuba divers.

Faulconer’s office estimates the dredging will yield 122,000 to 220,850 cubic yards of material. The mayor ought to know – he once sat on the powerful Mission Bay Park Committee. (See here for the City’s project description.)

This and other images are screen grabs from KUSI TV

It’s the first major dredging of Mission Bay in 5 decades.  During the work, which is expected to end in October, some beaches and sections of the bay will be closed.

Some of the media accounts of the dredging emphasis that the project will replenish – even “restore” – sands onto the bay’s beaches. Even Faulconer said:

“Preserving and protecting our environment is part of San Diego’s DNA and projects like this will help conserve our beaches and bays for the next generation.”

One media outlet reported: “The dredging will restore the floor to its original elevation, according to the city.”

But, listen, any talk of Mission Bay’s “original elevation” is meaningless. Originally, what we now call Mission Bay was once a huge lagoon, fed by natural creeks and the San Diego River. It wasn’t very deep – in fact, the Spanish first called it “Bahia Falsa” – False Bay.

Okay, so maybe, we’re talking about the original elevation of the human-made bay. Here’s a bit of history from the City website:

In 1944, a Chamber of Commerce committee recommended development of Mission Bay into a tourist and recreational center to help diversify the City’s economy, which was largely military. In the late 1940s, dredging and filling operations began converting the marsh into the jewel that is today Mission Bay Park. Twenty-five millions cubic yards of sand and silt were dredged to create the land forms of the park, which now is almost entirely man-made.

So, it’s not news that the priorities of the city vis a vis Mission Bay are all about boats and visitors. This has been going on for a long time. Up to the early 1950s, a bridge connected north Ocean Beach to south Mission Beach – a bridge that held a trolley track and from where hundreds of fishermen fished from. But it was demolished for the boats – as the bridge wasn’t tall enough for sail boats;  the people of OB were promised a pier in return, which was built and opened in 1966, about 15 years later.

Won’t the dredging disrupt those parts of Mission Bay being worked upon? Faulconer said we’re supposed to be “preserving and protecting” the environment. This is an unanswered question.

The city says some 15 million people each year visit Mission Bay Park, which is the largest aquatic park of its kind in the U.S. How many of those millions are on boats?

As a layperson, I have not heard of boats running into each other, had no idea that navigation was so bad for them in Mission Bay; I have friends who sail in Mission Bay and I’ve never heard them complain of the unevenness of the bay floor. I wonder if the city has a list of accidents or near-accidents or other boating mishaps to warrant such expense and such a project. (What is the expense? Each time I click on the budget for the project on the website – it times out.)

Plus I didn’t know the beaches at Vacation Island – a tourist attraction – and those at Crown Point were losing sand.

Oh well, I’d feel more assured if there was a bevy of environmental scientists telling us we need to dredge the floor of Mission Bay to make it more even for the boats. But there isn’t.

In fact, the San Diego Audubon Society has learned that possibly the city is not the best organization to manage the environment around the bay. And just recently, bay committees and park and rec boards are telling us that a land-grab by a huge hotelier is really just consistent with the Mission Bay Master Plan.

Sources:

NBCSanDiego

KPBS

KUSI

San Diego County News

From the City:

For questions or concerns about the project, please contact the project community liaison Alli Berry at 619-538-0777 or aberry@curtinmaritime.com. You may also call the Public Works Department construction project information line at 619-533-4207, email engineering@sandiego.gov, or submit your inquiry online. Please reference the “Mission Bay Navigational Safety Dredging Project” in your inquiry.