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story & photos by Tyler Kindred
For three decades San Clemente has been increasingly losing the sand supply along her coast. Due to the development of South Orange County and growth in the San Juan Creek Watershed, natural sediment flow cycles have been disrupted, resulting in less sediment making it to our shoreline.
The sand erosion issue is not unique to South Orange County, nor to the western coast, as many studies and projects have also been cited on the Gulf and East Coasts. While the exposed rocky surface may cause complaint from local beach-goers, replacement projects designed to transport sand supply can be costly. With help from the San Clemente City Council, Surfrider Foundation, and other community members, the Army Corp of Engineers stands ready to re-introduce a quarter million cubic yards of sand onto San Clemente’s beaches as an initial step against erosion.
We sat down with Tom Bonigut, Assistant City Engineer, to discuss the process of identifying and solving the sand supply issue.
1. When was sand erosion in San Clemente first noted as a serious issue?
It was mid to late 1990s; that’s when it first started getting on people’s radars. We had some major storms in the early ‘90s and they took away a big chunk of the beach, and the beach wasn’t building back like it had in the past. So in 1998 or 1999, the city established a temporary ad-hoc advisory committee. The beach advisory committee, with a lot of community leaders and environmental folks decided, ‘We need to start enlisting some help to figure this out.’ So that’s where this whole process of working with the Army Corp of Engineers started.
2. What studies have been undergone regarding the erosion?
The Army Corps of Engineers did an initial reconnaissance study, fully funded by the federal government, to do a quick look at what the problem and potential solution was. Then they started doing a number of coastal and environmental studies, bringing in consultants, and feasibility studies which the city actually helped pay for. There’s a whole range of studies we could list off, but it’s all packaged under an analysis that the Corp of Engineers led looking at coastal erosion, all starting around 2000.
3. What are the contributing factors?
In terms of a root problem, what the Corp determined in all their studies is that there have been changes over time as South Orange County has developed. We’ve never had a lot of sand compared to other areas. For our area San Juan Creek is the major source for sediment, which includes sand that helps to nourish the beaches. In the past, there was enough to periodically come down in the wet years, and that would provide a source and keep our beaches somewhat stable. Developments occurred in the San Juan Creek watershed and it was basically paved over; and the main creek itself started to become hardened which basically became channel walls in the tributaries. There’s just been less natural sediments applied; you still get those pulses of sediments in the wet years, but it just hasn’t been what it was in the past. So it’s this starving of the natural source that in the past has been enough to keep our beaches stable. Every year you get some of the major erosion from storms, but over the long term our shoreline has just been gradually eroding away. There’s been less sediment coming in, and it’s needed to keep the beaches stable.
4. We’ve heard that sand erosion may be caused by the Dana Point Jetty -
No, it really isn’t. They break up the coast into regions; kind of like a watershed, its own region for where all the runoff goes. They call it a ‘littoral cell’. And these are defined sections of coast where there’s a system of sand movement. So the Dana Point Headlands is at the North end of one of these cells which goes all the way down to La Jolla Canyon in San Diego County. It’s considered a system, where sand moves along the coast. North of Dana Point is part of a different cell, and there’s really not a lot of sand movement around Dana Point. The harbor and the jetty were kind of in the boundary where there was never a lot of sand transport going up and down coast. The harbor is not playing any significant role in our particular problem. You still get some sand buildups in the harbor once in a while, but I don't think anyone believes that it’s a significant contributor toward the problem. The harbor has been there for a quite a while, and even after the harbor was built, the beaches were doing okay. In the very big picture, it is a relatively recent problem- from about the 1990s on. And it has primarily to do with the development of the watershed and cutting off the natural sediment source we used to rely on.
5. What projects are scheduled to combat the erosion? What steps are involved to initiate these projects?
Well that’s our whole ten year saga (laughs). There are a lot of different strategies in coastal engineering. Through a series of workshops and studies, the main angle at this point is the ‘Beach Sand Re-nourishment Project'. In San Clemente, unlike areas in Newport Beach and the Santa Monica Bay, we’ve got a hard rock layer that comes pretty close to the surface; there’s really not a lot of sand here. The project would basically try to mimic and replace some of that natural sand via a sand replacement, or re-nourishment project. The way the sand generally moves is down the coast, and we're at the top of the cell where the sand migrates down to San Diego County. So we would take sand from an area off Oceanside in the ocean that is set up as an allowable place to pull sand out of, and bring it back to put on our beaches. We’d have to do this every six to seven or eight years. The Corps has identified that they have a very specific project to put about a quarter million cubic yards of sand on the beach. So, the second part of your question is, ‘how do we get there?’
The federal government has an interest in this because there are economic benefits and it’s good for the nation. We are currently in process of getting authorized for a federal authorization bill. That bill is called the ‘Water Resource and Development Act’, and its actually being worked on by Congress right now. We have a federal lobbyist who’s working to make sure our project gets included. Apparently, it is included in the draft version of the bill now, which Congress is expecting to act on at the end of the year. If they do that, then we’ll have what's called a ‘cost-share’; so we will have to try and figure out how to cover our share. There’s a kind of machinery in place to get this project to fruition; but it does take a long time unfortunately.
6. What other agencies are involved?
It’s basically the Army Corp of Engineers, as our partner and the one doing all the studies. As part of that, we’ve done coordination with others, like the Surfrider Foundation, as well as the community to get public input. I’ve personally been coordinating with Mark Rauscher at Surfrider. We’ve been trying to make express acceptance of the fact that if we dump a lot of sand on the beach, we won’t want to alter surf breaks. There’s a coastal engineer at the Corp who’s actually an avid surfer, and who’s been advising and guiding this project.
7. Have similar problems have been cited on other beaches?
Yeah, this isn’t unique to San Clemente. There are various sand replacement projects that are just being finished up along a lot of the San Diego County coastline. They have similar issues. San Diego has been developing just like South Orange County; they're losing sand supply. They have been doing this longer, so that’s our nearest neighbor. I’m sure it’s happening in other parts of Orange County, and up and down the California coast. It’s really common in the Gulf Coast states, in Florida and back East. Where there’s this loss of sand, sand nourishment can be a popular option because it's viewed as more preferable than just putting sea-walls or revetments to protect property. You’re getting a benefit because you’re building back the beach that people can use, and you don’t have hard structures. Our community has told us they don’t want more hard structure; they want to take the soft approach.