Photo is of the first observation pier along the Harborwalk overlooking Coleman Beach. The report said there was ‘missing rock revetment, erosion, and undermined observation deck footing’ here and the situation is of ‘moderate’ priority.
Several years ago, a group of citizens put forth a parcel tax in Morro Bay to fund what at the time was thought to be about $10 million in needed repairs to the City’s harbor infrastructure.
The tax was proposed at $10 a month for every privately owned piece of land in town, some $120 a year each. But voters soundly rejected it.
Now, the City has a much better understanding of the extent of the infrastructure repairs needed on the waterfront, and $10 million was more of a drop in an ocean-sized bucket.
The City recently released a draft assessment it commissioned looking at the revetments and seawalls that line the edge of the waterfront and keep the ocean at bay.
Completed by a company called Brady out of San Diego, the study is called, “Inspection and Assessment of Revetments and Seawalls,” and utilized visual and high-tech inspections of the continuous pile of rocks that line the waterfront from Morro Rock to the boat launch ramp.
For years, the City has talked about a deteriorating revetment at all of its lease sites, one of several public facilities and structures that make up the waterfront. Brady’s study was conducted last June 19-21 and sought to prioritize the worst areas and work up some preliminary cost estimates.
Photo is of the revetment from the South T-pier looking south towards Stax Wine Bar. The lighter rocks are an old repair, and the darker ones signify where the rocks have slipped down towards the water, steepening the edge, which supports a section of the Harborwalk.
“A routine above-water inspection,” reads the Brady report, “was performed on visible portions of the structure(s) by walking, and at times, utilizing a small boat as needed for access. This inspection was used to form a general understanding of the condition of the 12 revetments and three seawalls with the purpose of identifying and prioritizing repairs.”
Some areas needed more high-tech study, to include “a Revetment and Seawall survey by eTrac, a geophysical study using Ground Penetrating Radar by GeoVision, and Conceptual Geotechnical recommendations by ENGEO. The results of these studies informed the overall condition of the revetments and seawalls.”
Photo shows the patchwork revetment out front of the Harbor Office between Morro Bay Oyster Co., and the North T-pier. The Brady report said this area was in ‘serious’ condition.
As might be expected, the levels of deterioration varied. “The existing condition of the revetment locations and seawalls range from needing minor maintenance to complete failure,” the report said.
The report only looked at areas of the revetment in between lease sites, such as the area below the road ends and adjacent to parks and public viewing piers. Revetments under lease sites are the responsibility of the leaseholders and could be in better or even worse shape.
The revetment was divided into roughly 100-foot segments for the report and the report said there are some common needs that run through them.
Photo shows the revetment at the edge of Morro Strand Beach and the Rock parking lot. The report said ‘The top of the slope is not protected. Erosion of fine material is seen at the top, large voids, and missing rock is noted.’
“Common recommendations,” the report said, “include controlling surface drainage, adding rock, revetment refurbishment, and revetment rebuilding. Controlling surface drainage may include grading ditches, swales, or berms; drains; concrete, metal, or plastic structures; or other methods designed by a civil engineer.”
The various segments looked at include the revetment at the edge of the Morro Rock parking lot, and down past the launch ramp to the seawall at the Inn at Morro Bay, which has been failing for many years.
In the study, and among the most visible failings is the area at the edge of Morro Strand Beach and the rock parking lot. That area has numerous spots where large boulders have fallen away, and the topsoil has been eroding. Still, the report lists this area as in “fair condition” with minor to moderate damage.
The City created a “walkway” of sorts along that rock revetment many years ago by installing a line of medium sized boulders, culled from the detritus at the base of Morro Rock, to pull the parked cars back from the bluff top and prevent accidents.
These rocks and the thousands of people a year that visit the beach here make for some treacherous footing for those who try to clamber down the rocks to the sand. For convenience, and to provide beach access for emergency vehicles, the City created a sloped sandy ramp at the far northeast corner of the parking lot. Though the sand is loose, it’s probably better footing than among the loose and teetering boulders just a short distance away.
The area directly in front of the Harbor Office by the North T-pier is in serious condition and has “moderate” to “major” damage. That area at some point in the past was covered with shotcrete and has what appear to be slabs of concrete sidewalk that have been dropped onto it.
“Where the concrete ends,” reads the study, “significant voids were recorded, up to 6 feet deep.”
A 1-way alley runs along that revetment and past the Harbor Office and Coast Guard stations. There are some areas where the undermining has started to affect the road.
And at Anchor Memorial Park, adjacent to House of JuJu, the rocks are again slipping and exposing the underlying soils, which have begun to erode as well.
The small public pier there is a remnant of a much larger structure that once spanned the bay and landed on the Sandspit. That old wooden, and rickety pier too has been undermined at the support slab supporting the first bent (sets of piles). The study recommends this be repaired.
On one other part of the revetment, the area between Dutchman’s Landing and the marina at Marina Square (Morro Bay Marina) the revetment is far too steep and is beginning to affect the sidewalk that runs along the end of Pacific Street.
Of the three seawalls inspected two were deemed “beyond repair and should be replaced.” The study said the seawalls can either be replaced in kind or reinforced by revetment rocks being placed in front of them.
As for the costs, the estimated costs for needed repairs runs from a low of $36.42 million to a high of $54.63 million.
The most expensive at $10.18M to $15.27M is the long segment along Coleman Drive.
As for the two failed seawalls, the estimated total to replace them with a new revetment is from $2.03M to $3.04M. Rebuilding them would be considerably more expensive.
It must be noted that the cost estimates in the study are the “opinions” of Brady and could be spot-on of off by a mile. “It is recognized,” the study said, “that neither the client nor the consultant has control over the costs of labor, equipment or materials, or over contractors’ methods of determining prices or bidding.”
The City Engineering Department plans to make presentations to the Harbor, Public Works, and City Council on this report sometime this spring. If readers want to look through the report it’s available on the City website, see: www.morrobayca.gov//CivicAlerts.aspx?AID=2926 to download the pdf file.
