The City recently added a last-minute $5 million flood control project to its Leucadia Streetscape plan. City planners claim that it makes sense because since they are going to rebuild the entire Leucadia Highway 101 corridor, it’s prudent to install much needed and overdue stormdrain modifications to carry floodwaters northward to Batiquitos Lagoon.
But, according to Leucadia resident, Dr. John Helly, a UCSD scientist, who spoke at the City Council meeting, it could create a host of new problems. He says that the City is rushing to a solution in order to keep to their schedule of breaking ground on Streetscape later this year, instead of taking the necessary time to solve a complex problem.
The flooding problems in Leucadia are due to the shape of the terrain. North Coast Highway 101 and the train tracks run through the long low point of the area, which is where most of the flooding takes place. Before houses, driveways, and roads were built, rainwater soaked into the ground in an even distribution so there was much less runoff pooling in the low areas.
Temporary pump in alley 
Leucadia Roadside Park
But today, during a storm event, rainwater hits those impervious surfaces and rinses off contaminants left by passing cars, roof debris, animal (and sometimes human) fecal droppings, and even dangerous heavy metals that slough off beneath the train tracks. Instead of soaking into the ground, this contaminated water pools up around businesses lining the 101.
There currently is a 24-inch diameter drain pipe that runs beneath the 101 carrying stormwater to Batiquitos lagoon that the City also uses to drain the flooding along Vulcan near Union Street by manually opening a valve to divert water from east of the tracks to the west side. Consequently, during storms, this pipe often is filled to over-capacity and the water backs up causing flooding on streets and alleys. City crews rush in to pump out the critically flooded areas, sending long hoses up and over the ocean bluffs. Some flooded areas are pumped to other spots to distribute the pooling water.
Ultimately, the stormwater ends up (1) in Batiquitos Lagoon, (2) in the groundwater which percolates to the bluffs and (3) in the ocean at Beacons, via the pumps at Leucadia Roadside Park.
At a starting price of $5 million, the proposed solution is to build a 60-inch diameter drainage pipe that will run along the 101 beside the 24-inch older pipe to increase the volume of the contaminated and untreated stormwater being carried away to the lagoon. both the speed and the amount of water being carried away. This new pipe will deliver water directly to the lagoon without any filtration. The City’s consultant, Tom Ryan of Q3 Engineering, claims this isn’t a problem because, historically, that’s the way we’ve been doing it.
But, according to Dr. Helly, the City is pretending that this is an insignificant change to the way things have been done and have even made these claims to the California Coastal Commission in a recent filing. The ‘insignificant change’ argument is based on what is called a ‘one-year storm’ which would not cause flooding anyway. However, the system is being designed for a ‘100-year storm’ and will have to be operated to contend with much more frequent 5, 10, 20-year storms that do cause flooding. In other words, the city is publicly pretending that there will be no pollution impacts to Batiquitos Lagoon by using the ‘one-year storm’ argument so they can rush changes in place to speed Streetscape development and avoid having to complete a proper watershed analysis and build a system to process the stormwater and suspended sediment before dumping it in the Lagoon.
They’re designing drainage for a 100-year storm but then justifying it by saying there won’t be any environmental impacts because it won’t reach that level in a 1-year storm.
Dr. John Helly
In the meantime, the City continues to spend money on disconnected parts of the stormdrain system in Leucadia and further contends that these are not related to Streetscape and that they are ‘insignificant changes’ to the Coastal Development Permit (CDP) and Local Coastal Development Plan (LCP).
The City has already begun building new stormdrain outfalls into Batiquitos Lagoon under the cover of hotel-related construction at LaCosta Avenue and Highway 101 apparently so they can later claim that this will all be connected to pre-existing outfalls into the Lagoon. This is shown in the proposed stormdrain design in GIS data received by Dr. Helly from the City as the result of a Public Records Act request. Dr. Helly and former mayor of Encinitas, Ms. Sheila Cameron, previously tried for over a year to get the City Engineer, Mr. Ed Wimmer, to convene a Technical Working Group on this problem but were repeatedly re-buffed by Mr. Wimmer and ultimately by the City Council in a public meeting.
from moonlightbeach.com, link below
Resources
City Council meeting where drainage solution was discussed
Addendum to a Final Environmental Impact Report
Moonlightbeach.com Cottonwood Creek article
by Julie Thunder