What is the Correct Definition of a Wetland Restoration?
This website might help:
the federal EPA's website features this definition of "restoration" as stated by the National Research Council (NRC). In its 1992 report, Restoration of Aquatic Ecosystems, NRC defined restoration as the "return of an ecosystem to a close approximation of its condition prior to disturbance."
http://water.epa.gov/type/wetlands/restore/defs.cfm
Definitions & Distinctions | Restoration | US EPA
The question is what year do you return to? 200 years ago or 4000 years ago?
I agree in part with Ruth Lansford (founder of the Friends of Ballona Wetlands) that some things cannot be changed, such as there will always be roads cutting through the area; there will most likely always be polluted water in Ballona Creek; there are older low-lying neighborhoods in Playa del Rey that we need to avoid flooding, just as there are new condos at Playa Vista that are served by roads that could be flooded by future sea level rise. So in the state's plan for flooding the wetlands full-time comes secondary impacts that may affect all of us in the pocketbook.
That is part of the controversy in the proposals for restoring the Ballona Wetlands. The basic engineering in the State's "preferred" plan mimics not the conditions of "prior to disturbance", which logically is about 200 years ago when the wetlands were a low lying river delta region which had only a limited connection to the ocean except in winter, when floods would break through the sand bar. Instead it mimics a full time always-connected to the ocean bay-like area which last occurred here 4000 years ago. To do this is estimated to cost $100 million.
To see maps of the difference between 200 and 4000 years ago, see this link:
These differences are described in the State's existing conditions report, which is posted here:
https://drive.google.com/file/d/0B5SGRAMv8RXub2hjTzFjN0FEMVk/view?usp=sharing
the federal EPA's website features this definition of "restoration" as stated by the National Research Council (NRC). In its 1992 report, Restoration of Aquatic Ecosystems, NRC defined restoration as the "return of an ecosystem to a close approximation of its condition prior to disturbance."
http://water.epa.gov/type/wetlands/restore/defs.cfm
Definitions & Distinctions | Restoration | US EPA
The question is what year do you return to? 200 years ago or 4000 years ago?
I agree in part with Ruth Lansford (founder of the Friends of Ballona Wetlands) that some things cannot be changed, such as there will always be roads cutting through the area; there will most likely always be polluted water in Ballona Creek; there are older low-lying neighborhoods in Playa del Rey that we need to avoid flooding, just as there are new condos at Playa Vista that are served by roads that could be flooded by future sea level rise. So in the state's plan for flooding the wetlands full-time comes secondary impacts that may affect all of us in the pocketbook.
That is part of the controversy in the proposals for restoring the Ballona Wetlands. The basic engineering in the State's "preferred" plan mimics not the conditions of "prior to disturbance", which logically is about 200 years ago when the wetlands were a low lying river delta region which had only a limited connection to the ocean except in winter, when floods would break through the sand bar. Instead it mimics a full time always-connected to the ocean bay-like area which last occurred here 4000 years ago. To do this is estimated to cost $100 million.
To see maps of the difference between 200 and 4000 years ago, see this link:
These differences are described in the State's existing conditions report, which is posted here:
The difference between these two is that 200 years ago, we had three natural habitat types: saltwater, freshwater and upland wildflower areas, and that 4000 years ago, the area was mostly ocean water, like is proposed to be the dominant feature in the State's proposal. As the site will now be mostly wet, most of the long-used walking paths will be eliminated except for a trail around the perimeter.
Some have said that the state's plan seeks to replace the lagoons at Ballona which were open to the ocean all year-round that were lost to development.
I would agree that some of the western lagoon areas that are still present in the Ballona region (Ballona Lagoon, the Grand Canal, Del Rey Lagoon) were usually open to the sea year round, at least based on the historical USGS maps. These are owned by the City of Los Angeles. Additional lagoons shown on this map are now part of the Marina Del Rey harbor, which, contrary to popular belief, actually has fish and seals and other creatures. So it also functions as a wetland habitat. However, most of the state-owned lands at the Ballona Wetlands were not lagoons 200 years ago as mother nature had filled them in. Thus the state's proposal to turn them into lagoons is not historically accurate.
As page 17 of the 8/18/2006 Ballona Existing conditions report says:
"2,000
to 200 years ago - Fluvial sediments continued to fill the lagoon.
Deposited sediments resulted in coastal plain accretion in a
southwesterly direction and saltmarsh expansion west towards the inlet.
Altschul et al. (2005) inferred that a double barrier at the inlet
formed about 1,000 years ago as a result of the sediment-rich
environment and that extensive mudflats also formed within the lagoon.
By 200 years ago, sediment accumulation almost entirely eliminated the
lagoon and formed a complex of salt and freshwater marshes, ephemeral
freshwater pools and sandy islands behind the barrier.
At this stage the marshes extended south to El Segundo Sand
Dunes and Del Rey Bluffs, north beyond Ballona Lagoon and Venice Canals
and east as far as the confluence of the Ballona and Centinela Creeks."
In order to create the state proposal, 20 feet or more of dirt must be scooped out of 100's of acres of the marsh, and it would be dumped on the south side along Jefferson and Culver Blvds. rising 10 to 15 feet above these roads. These might be very conveniently beneficial to Playa Vista's condos as Jefferson and Culver are in a tsunami zone and tall (and un-natural) earthen walls would prevent flooding there. But should our state-owned wetlands be filled in so as to prevent flooding their condos which they built in a flood plain when they must have known that climate change, or whatever you call it, was causing the threat of sea level rise?
The dirt would also be dumped in the location preferred by the Annenberg Foundation for their supermarket-sized nature center complex near the 90 freeway, giving them an unnatural hill that will undoubtedly give them an ocean-view site where there is not one now.
The state plan also features removal of the levees along Ballona Creek, which while they are not-natural, this would allow the heavily polluted water in the creek to pour into the protected wetlands, leading to a different and worse non-natural result. The cost of cleaning up the water in Ballona Creek is estimated at $3 billion, and that is not mentioned in the $100 million cost estimates of a restoration plan that removes the Ballona Creek levees. This is a good reason to not remove the levees.
So ultimately, the state's plan features an unnatural deep ocean bay filled with urban polluted street drainage and two areas of unnatural hills. I am sure that engineering firms would love this plan but it is not historically accurate. So it's hard to call it a restoration. This is why I support keeping the levees, and restoring the wetlands to a marshy delta concept that is first, more like what the area looked like "prior to disturbance" when development of this area began and second, it requires less land alteration and habitat destruction with bulldozers and will thus cost much less. Finally, it preserves more of our trails and existing wildlife biodiversity.
To see an artist's rendering of a marshy delta restoration:
https://goo.gl/photos/edDobu8JsmFzAe5p9
...Rex Frankel
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