|
BACKGROUND INFORMATION
OWNER INFORMATION
County of Orange
300 North Flower Santa Ana CA
Bryan Speegle Director Resources & Development Management Department
714.834-4643
PHYSICAL DESCRIPTION OF THE COASTAL BEACH
Owned in fee by County of Orange
Harbors, Beaches and Parks, CSA 26,Sandy, ocean-facing
beach bisected by Aliso Creek, has a rocky inter-tidal
zone at south end of beach, coastal access provided off
of Pacific Coast Highway, two public parking lots provided,
parking fees charged. Usage is swimming, body surfing,
skim boarding, sunbathing, surf fishing, tide-pool exploration.
PUBLIC HEALTH OR WATER QUALITY PROBLEM
Aliso Beach is a popular
south Orange County beach that averages 120,000 visitors
per month attendance for an annual total of 1,148,374
visitors. Aliso Creek drains a 35-square mile watershed
area that has experienced significant commercial and residential
development in the last 20 years. Portions of the Cities
of Laguna Beach, Laguna Niguel, Aliso Viejo, Aliso Woods
Mission Viejo and Lake Forrest all drain into Aliso Creek.
Urban runoff, adverse water quality due to high bacteria
counts, sewer spills and erosion all impact the recreational
value of the creek and its outlet at Aliso Beach.
Aliso Beach was closed an
average of 16.5 days per year due to contamination from
broken sewage pipes, urban runoff and stagnation of creek
water (data provided by the US Army Corps of Engineers
Feasibility Study for Aliso Creek).
Posting Log for the year
1999-2000 has been attached indicating closures, postings
and types and quantities of bacteria or other conditions
A listing of references related
to studies of Aliso Creek and water quality monitoring
programs (both existing and proposed ) have been attached
Urban runoff appears to be
one of the primary sources of bacteria and end of the
pipe treatment coupled with source control appear to be
the best mid-term solution until longer term projects,
currently under consideration in the Corps of Engineers
Feasibility Study, are implemented.
PROJECT INFORMATION
The project proposed to install
a "Clear Creek" treatment system at two locations.
The purpose of the "Clear Creek" system is to
harvest water from Aliso Creek and reduce the total dissolved
solids TDS (salts) in the Aliso Creek water. Thereafter
this treated creek water can either 1) be blended with
secondary effluent from a local water treatment plant
and then used to irrigate a golf course or 2) the treated
water can be returned to Aliso Creek.
PROJECT LOCATION
Two locations are being proposed
for "Clear Creek" type treatment solutions in
conjunction with our water district partners. The first
location is upstream of the beach outlet and near the
South Coast Water District Treatment plant. At this location,
0.5 MGD of creek water will be removed from Aliso Creek
and transmitted to the chlorine contact chamber where
it will be blended with 1.0 MGD of secondary effluent
from the Coastal Treatment Plant. The water will then
be transmitted to Aliso Creek Inn Golf Course for irrigation
with water of acceptable salt content. Possible expansion
of treatment program will require additional coordination
with the Fishery Resource Agencies.
The second project location is further
upstream and is proposed in partnership with the Moulton
Niguel Water District. The project calls for the identification
of a "hot spot" that lends itself to a "Clear
Creek" type solution. Project will identify amount
of water that Moulton Niguel Water District can accommodate
for treatment, treatment method and potential source for
reuse. The exact location has yet to be identified and
the selection will be based on an evaluation of the data
accumulated in the Water Quality Control Board 13225 Directive
to monitor of 35 storm drains in the watershed.
PROJECT GOALS
Both projects propose using a "Clear
Creek" type approach to treatment. Typically Clear
Creek needs a constant flow from an impounded and settled
(reduced suspended solids) source of water. Minimal impact
approach calls for an inlet pipe with strainer be installed
which does not alter the streambed and hence does not
invoke permitting issues. If this approach cannot be implemented
then a diversion dam and sump need to be designed and
installed. The project may include an inflatable dam located
downstream of the Coastal Treatment Plant that provides
the added benefit of containment of any potential spills.
Data acquired during the 13225 Directive Monitoring shows
that at various locations along the Aliso Creek Mainstem
there exist physical conditions that assist in bacterial
growth and die-off. The treatment and reuse project at
the lower reach near the Coastal Treatment Plant provides
the most direct impact to reduction of bacterial loading
at Aliso Beach. Treatments of "hot spot" pipes
that most significantly impact the Aliso Creek Mainstem
water quality also appear to be a high priority way of
improving water quality. The project goals would be to
determine if substantial reduction in bacterial loading
from the watershed results in substantial reduction in
beach postings and closures.
PHYSICAL DESCRIPTION OF PROJECT
Local environmental groups as well
as the two Water Districts and the County support the
implementation of a "Clear Creek" type treatment
process. Two reuse options exist: 1) the treated water
can be used by the local water district to supplement
their recycled water system and can also be used for irrigation
purposes, or 2) due to the high salt content, the water
will be treated and returned to the creek for habitat
purposes. This latter option is supported by state and
federal regulatory agencies that do not want the creeks
to "dry up" and loose habitat value. At each
project location the most appropriate option or a combination
of options will be pursued. A "Clear Creek"
solution provides for various treatment options depending
on site-specific requirements. It is also a portable system
that allows for better access to "hot spots."
PLANS AND SPECIFICATIONS
Plans, specifications and detailed
costs are not available for the project at this time.
TIMELINE
Project implementation at the coastal
treatment plant is scheduled for late 2001. The next milestone
will be implemented within six months of this time.
FINANCIAL EVALUAION
Not available at this time
ENVIRONMENTAL DOCUMENTS
Environmental documents will be
prepared to satisfy CEQA after plans, specs and estimates
are completed.
LOCAL ISSUES
An MOU will be prepared with the
City of Laguna Beach and AWMA (or its successor) for project
funding
All local (City of Laguna Beach) and regional (County
of Orange and state Coastal Commission) permitting issues
will be complied with if determined to be necessary.
|
