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Ongoing Projects
The ongoing investigations of probable sources for the bacterial
contamination in the waters off of Huntington Beach were divided into several projects.
The data-gathering phases for many of these projects occurred between May 3 -17, 2000.
The weather during this principal sampling period was dry except for a small storm
event that occurred near the end of the data-collection period [rain gauges showed
no measurable rain in the vicinity of the study and only traces in other parts of
Orange County on May 15]. Water-quality samples collected for these studies normally
were analyzed for total coliform (TC), fecal coliform (FC), and enterococcus (ET)
bacterial concentrations. The following projects were presented to the Panel:
Temporal and Spatial Intensive Water-quality Sampling
Water-quality samples were collected at several sites along
Huntington Beach in ankle-deep (standard) and waist-deep waters every hour for the
defined 2-week sampling period in May 2000 to determine typical temporal and spatial
changes in water quality. More limited water-quality samples were collected at sites
beyond the surf zone. The data from this project were not presented to the Panel.
Panel Comments:
When the data are available, the Panel strongly recommends that statistical and other
analytical methods be used to determine the temporal and spatial patterns of bacterial
contamination. In particular, it would be useful to determine the temporal variability
of the contaminants on daily cycles, tidal cycles, and over the 2-week sampling period.
In addition, the spatial coherence and the associated lateral extent of the contaminated
patches should be determined.
This data set should be integrated with other data sets collected during the same
time period. Suitable data sets include the water-quality samples collected at sites
within Talbert Marsh (TM), within the watershed, and from the groundwater. The synthesis
should include the traditional water-quality data collected by OCSD as well as extensive
spatial and temporal physical oceanographic data sets collected in the adjacent coastal
ocean.
The analysis of contiguous data sets will help determine the
possible sources of contaminants and the processes that cause contaminants to move
along the beach. An examination of temporal patterns in the hourly data may determine
how representative are the daily water-quality samples traditionally collected by
OCSD. Results will help determine whether it is advisable for OCSD to sample water
quality at a specified tidal stage rather than at a specified time of day. Understanding
these patterns will also help determine how historical OCSD databases can be used
to better understand contaminant patterns.
Contaminants in the Local Watershed
Bacterial contamination was measured at several sites in the local watershed and storm-drain
systems. Even though data were not presented to the Panel, the presenters stated that
high contaminant levels were found at several sites in the watershed, particularly
downstream of local restaurants and in entrances to the storm-drain systems.
Panel Comments:
The Panel was not given details of how the sanitary surveys were conducted. In particular,
grid-sampling protocols were not specified. The Panel would like to know if there
are defined, standard protocols for sanitary surveys and if those protocols were followed.
Were sample sites chosen at random or were sites chosen to be near known contaminant
sources?
The Panel recommends further analysis of the data. These contaminant data should be
related to the water-quality samples collected in the TM surveys and in the water-quality
surveys along Huntington Beach. If possible, it would be advantageous to determine
the rate of bacterial growth (positive or negative) in the watershed and storm-drain
systems. The bacterial indicators at contaminated sites could be fingerprinted.
 
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OC
Sanitation District - Huntington Beach Closure Investigation Phase
I 
PFRD
Medium Range Strategy
