|
The report addresses the following four areas identified in the directive:
The results of the weekly monitoring (see Monitoring
Results below);
A description of the Permittee's efforts to identify
the persistence, the significance and, to the extent feasible, the causes of the
impairment or exceedance, and to the extent feasible, the technical and economic
feasibility of control actions available to the Permittees to reduce or eliminate
the impairment or exceedance (see Actions Taken by Permittees
below);
A description and evaluation of the effectiveness of
the structural and non-structural Best Management Practices ("BMPs") currently
implemented to ensure that the discharge of bacteria and other pollutants to the
storm water conveyance systems, which discharge specifically to the Creek or its
tributaries is prevented (see Effectiveness of Actions
below); and
An update of the time schedule and work plan for eliminating
sources of bacteria and measures to prevent pollutants from contributing to any
violation of the REC-1 standard (see Actions for the Upcoming
Quarter below).
Monitoring Results
Monitoring was conducted weekly for ten weeks during the April
to June quarter at 35 storm drain inputs (“inputs”) of 39 inches or greater
to Aliso Creek, Wood Canyon Channel, Sulphur Creek and English Canyon Channel ("the
receiving waters"). The constituents monitored were total coliform, fecal coliform,
Enterococcus, estimated flow, pH (monthly)
and total chlorine (monthly).
In response to the May 15, 2001 directive clarification letter
from the San Diego Regional Board, a field reconnaissance was conducted to identify
any additional inputs smaller than 39 inches with daily flows greater than 100,000
gallons. None were identified.
In addition, the Permittees conducted monitoring in the receiving
waters upstream and downstream of each input at approximately 60 locations to provide
information on the overall health of the Aliso Creek watershed and to characterize
the significance of the inputs on the Creek. This information will also be important
in helping to prioritize the inputs that have the greatest impact on recreational
areas of the Creek where water contact recreation most frequently occurs (see Actions
for the Upcoming Quarter below).
The main findings of the first quarter monitoring are as
follows:
The bacterial quality at the Creek mouth, immediately
upstream of the beach where most water contact recreation occurs, slightly exceeded
the REC-1 criteria during two consecutive 30-day periods (geometric means of 427
MPN/100 ml and 226 MPN/100 ml for fecal coliform vs 200 MPN/100 ml for the REC-1
criteria)
The bacterial quality in the receiving waters was above
the REC-1 and REC-2 criteria in many locations (the REC-1 criteria was not met 99%
of the time and the REC-2 54% of the time)
The bacterial quality in the inputs to the receiving
waters was elevated in most locations. While the inputs are not designated as having
a recreational beneficial use, comparison to the REC-1 and REC-2 criteria for discussion
purposes only indicates that these thresholds were frequently exceeded (the REC-1
criteria was not met 99%of the time and the REC-2 criteria 89% of the time)
Low fecal coliform levels were found in Laguna Niguel
Lake, indicating that the Lake attenuates the elevated inputs from Sulphur Creek
Flow estimates indicate that a cumulative flow of approximately
3.79 cfs (1701 gpm) was monitored from the inputs during the ten-week monitoring
period
The pH in the inputs was within an acceptable range
(6.5 to 8.5) in the majority of measurements (94% of the time)
Total chlorine, which indicates the presence of water
disinfectants, was detected in all inputs. In 57% of these samples the concentration
of total chlorine exceeded 0.1 mg/l
Statistical analysis of the data suggests that factors
other than the bacterial concentration measured in the inputs may influence the
concentration of bacteria in the receiving waters. These factors could include flowrate
in the receiving waters at the point of discharge, direct wildlife inputs to the
receiving waters, depositional/turbulence processes, etc.
The monitoring program will be increased during the second
quarter as follows:
Actions Taken by Permittees
The actions taken by the Permittees during the reporting period
were primarily driven at the outset by activities that were directly required by the
directive from the San Diego Regional Water Quality Board and its subsequent clarification
letter of May 15, 2001:
Development, submittal and subsequent funding and implementation
of the
alternative monitoring strategy.
Conducting a field reconnaissance to identify additional inputs
with daily flows
greater than 100,000 gallons per day.
Preparation of a joint Initial Report by all the Permittees,
which was submitted on
April 30.
The Permittees also continued to implement the ongoing Best
Management Practices (“BMPs”) that are most likely to improve bacterial
water quality such as drainage facility maintenance, catch basin stenciling, street
sweeping, public education, new development BMPs and activities to detect and eliminate
illegal discharges and continued to pursue implementation of the structural retrofitting
projects identified in the Initial Report. The following new activities or enhancements
were initiated during the quarter:
- The City of Laguna Niguel installed a dozen curb face grates
to determine their
- The County, in cooperation with all cities countywide, finalized
for distribution two new public education brochures on Restaurant Cleaning Operations
and Homeowner Tips for Pesticide Applications and updated a third on mobile detailing
- The County held a training and coordination meeting for authorized
inspectors of city water quality ordinances
- The Permittees were notified that Proposition 13 grant funding
would be made available to support part of the construction cost of the Dairy Fork
Bio-Filtration Basin, the Munger Storm Drain Infiltration Basin and the WetCAT Network
for J03P02. This funding will be available before the end of the year
- Planning for many of the grant projects continued. The City
of Laguna Niguel, for example, as part of the North Wetland of the WetCAT Network
project conducted a gnatcatcher survey, prepared a draft mitigated negative declaration
and worked with the Kite Hill Homeowners Association on conceptual project approval
- The County worked with the Coastal Commission for approval
of the temporary, seasonal diversion of Aliso Creek at it mouth to the sanitation
ocean outfall. The Coastal Commission approved the permit subject to the County
meeting specified conditions and the Orange County Board of Supervisors has approved
a resolution
committing to implementing two pilot projects in the watershed requested by the
Coastal Commission:
- A 0.5 million gallon per day pilot project treatment
of water from the lower reach of Aliso Creek for beneficial reuse as irrigation
water
- Implementation of a treatment strategy at an additional
storm drain input beyond those identified for Dairy Fork, Munger Storm Drain
and the J03P02 WetCAT Network
The diversion project will be implemented in August and is expected to reduce
beach contamination postings
Effectiveness of Actions
The Permittees were able to conduct a long term trend evaluation
of the dry-weather, total coliform levels at the Creek mouth from 1996 to 2000 and
compare it to a similar (though less extensive) data set for 1975 to 1982. The geometric
mean of all the dry-weather, total coliform measurements from 1996 to 2000 was 1965
MPN/100 ml
compared with 3226 MPN/100 ml from 1975 to 1982 (the means are significantly different
by t-test). The results of this analysis show that the geometric mean total coliform
levels are comparable to approximately twenty years ago and indicate that elevated
total coliform levels have long been present at the Creek Mouth.
More immediate indicators of effectiveness can be obtained through
either conventional water chemistry monitoring or the assessment of non-conventional
data. With respect to the latter, the California BMP Manuals suggest that program
effectiveness can be gauged through other measures, such as quantities of materials
diverted from the storm drain system and increased public awareness as measured by
public opinion surveys. The following are examples of both types of evaluation being
pursued by the Permittees:
Performance monitoring of the existing East Wetland of the
WetCAT Network has shown that fecal coliform removal rates were 90 to 99.9%. Further
BMP effectiveness studies have been incorporated as part of the projects for the
Dairy Fork Bio-Filtration Basin, the Munger Storm Drain Infiltration Basin and the
WetCAT Network for J03P02 and will be completed as these projects are built. This
information will be presented in subsequent quarterly reports.
Data for activities such as drainage facility maintenance,
and street sweeping were provided for the 1999/00 period in the Initial Report.
709 cubic yards and 3171.6 tons of debris were diverted from the storm drains by
these Permittee activities. Comparisons with the 2000/01 data will be possible in
the third quarterly report.
A countywide public opinion survey is currently being planned
to determine the current level of public knowledge of water quality issues. This
will provide important information for determining the appropriate educational messages
to be used in the Aliso Creek watershed and provide a baseline for future determination
of the effectiveness of the public education effort. The results of the survey should
be available for inclusion in the third quarterly report
Actions for the Upcoming Quarter
The Permittees identified a significant number of ongoing and
proposed activities for improving water quality in Aliso Creek in the Initial Report
and in this Progress Report. These activities continue to be worked on during the
second quarter and, additionally, the following new efforts will be initiated:
- The results of the monitoring data from the first quarter
have provided a significant tool for further focusing the Permittees future efforts.
The Permittees intend, for the balance of the second quarter, to prioritize the
inputs to the receiving waters based on their impact on the highest used recreational
areas of the Creek. This will be accomplished by the following actions:
- Collecting additional monitoring data, as described in
the section on Monitoring Results above
- Inventorying areas of recreation in the Creek to update
and expand the list provided in the 205(j) Water Quality Planning Study
- Updating the comparison of storm drain inputs to incorporate
recreational use as a factor in order to identify those inputs that have the
most significant impact on high use recreational areas
- Each Permittee will select at least one high priority
storm drain input for intensive investigation and improvement in the remainder of
the second quarter and into the third quarter involving:
- Preparation of drainage boundary maps for the selected
storm drain input that includes, but is not limited to: land use types, topography,
major sewer lines, reclaimed water lines, septic systems, homeowner or community
association areas and jurisdictional boundaries
- Field reconnaissance for potential causes such as illicit
connections, illegal discharges, accumulated waste materials and seepage through
the joints of the storm drain that may be indicative of sewage or groundwater
- Increased cleaning of identified problem catch basins
and debris accumulated in the storm drains themselves as a follow-up to the
field reconnaissance
- Focused public education through appropriate newspaper
articles, inserts in homeowners association newsletters or direct communication
with residents
- Identification of structural retrofitting opportunities
if they exist
Progress on these activities will be reported in the second
and third quarterly reports.
|
