With the berm and tidal gates in place, channel flushing will soon occur.
Crews in Reviving Your Wetlands restoration have put in place a system to manually control water flow in the inlet’s main channel connecting the ocean.
Now it’s time to open the newly constructed water control feature, or dike, for the first of many planned tidal flushes. The dike is in place because it will allow restoration crews to control water flow while dredging occurs in the Central basin of San Elijo Lagoon.
How sturdy is it? This berm is designed to withstand any rain storm event that may occur (including a 100-year flood) while allowing water runoff from the upstream Escondido Creek to flow out to the ocean.
Above: This berm, or dike (located along the Nature Center Loop Trail), will remain in place for the duration of our lagoon restoration.
Above: These gates will periodically be opened during low tides, which will match water levels upstream. The gates will remain open for a couple of tidal cycles; flushing the lagoon’s system.
Beginning today, the first tidal flushing will occur. The tidal flushing will continue throughout the weekend. Lagoon visitors and neighbors can expect equipment and evening lighting in the dike area during this process.
Above: The Ross Island Dredge No. 10 moves into the Central Basin channel through an opening in the dredge perimeter berm.
Soon, this opening will be closed again creating a perimeter berm that surrounds the overdredge pit. The perimeter berm will ensure that only the very top layer of water breaches out, and that the high nutrient sediment that is removed from the channels will remain in the pit.
Above: The Ross Island Dredge No. 10, now in the main Central Basin channel, is removing the temporary dikes and beginning to remove the accumulated high-nutrient (organically decayed) sediments from the middle, bottom, and side of the main channel to the overdredge pit.
The Ross Island Dredge No. 10 will operate Monday to Friday 24 hours a day. Lagoon neighbors and visitors may hear noise and see nighttime lighting near the Central Basin’s main channel. Excavator earthwork will occur Monday to Saturday 7 am – 5:30 pm.
During tidal flushing periods, water quality fluctuations may occur. This will be transient — much like what occurs with the annual excavation of the inlet.
Remember, that even during the channel flushing, we do not expect a decline in water quality that exceeds our rigorous permitting standards.
Read more about coastline monitoring. Conservancy restoration teams continually monitor and test lagoon and nearshore waters for pH, turbidity and dissolved oxygen levels within our permit guidelines.
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