bolsa chica new channel effect on shoreline water...
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Bolsa Chica New ChannelBolsa Chica New ChannelEffect on Shoreline Water Effect on Shoreline Water Effect on Shoreline Water Effect on Shoreline Water
QualityQuality
Douglas Moore, Ph.D. (OCPHL)Douglas Moore, Ph.D. (OCPHL)Charles McGee (OCSD)Charles McGee (OCSD)Martin Getrich (OCPHL)Martin Getrich (OCPHL)Patrick Pham (OCEH)Patrick Pham (OCEH)
Sampling Sites at Bolsa Chica State Beach and Huntington City Beach
Location of Future Channel and Two Added Study Sampling Sites: BCN and BCS
Bolsa Chica Wetlands after Channel Opening
Study OutlineStudy Outline
• Study utilized shoreline water quality data.Study utilized shoreline water quality data.• Pre-Channel June 7, 2005 – Aug 23, 2006• Post-Channel Aug 24, 2006 – Aug 27, 2007
– 5 sample sites for Bolsa Chica Site• Channel Opened Aug 24, 2006• 4 Beach Sites (n = 190 to 450 per site)( p )• 1 Mid-Channel Feb. 2007 – Aug. 27, 2007 (n = 25)
– 8 sample sites for Santa Ana River Site• Date range from June 7 2005 Aug 27 2007• Date range from June 7, 2005 – Aug. 27, 2007• 5 Beach Sites (n = 440 to 450 per site)• 3 Channel Sites ( n = 450 to 480 per site)
Study DetailsStudy Details
• Collection & Testing conducted by Orange County Sanitation g y g yDistrict. Total Coliforms, Fecal Coliforms, & Enterococcus Tested.
• Data analysis by OC PHL & OC EH
• Dry weather data only, rain periods excluded
• Statistical Analysis• Statistical Analysis– Geomean– Failure rates – single samples exceedances– Differences in values before and after channel opening
• The Mann-Whitney U – nonparametric rank test
Bolsa Chica Enterococcus Data, All SitesN = 1289
3.00
PostPre
Channel
2 00 104 CFU/ 100 ml
og (E
NT)
2.00 104 CFU/ 100 ml
Lo
1.00
Geomean 5.2 CFU/100 ml
Date
0.0001/0112/0111/0110/0109/0108/0107/0106/0105/0104/0103/0102/0101/01
Bolsa Chica Geomean of Single Sample LevelsBolsa Chica, Geomean of Single Sample Levels
30Pre Channel Post Channel
**
15
20
25
00m
l
5
10
15
CFU
/1
0
5
TC FC Ent TC FC Ent TC FC Ent TC FC Ent TC FC Ent
33N BCN CHAN BCS 27NSite/Indicator
* Statistically significant for p < 0.05, by Mann-Whitney U Test
Bolsa Chica % Single Sample ExceedanceBolsa Chica, % Single Sample Exceedance
5 0%
6.0%
nces
Pre Channel Post Channel
3.0%
4.0%
5.0%
Exce
edan
0 0%
1.0%
2.0%
Sam
ples
E
0.0%TC FC Ent TC FC Ent TC FC Ent TC FC Ent TC FC Ent
33N BCN CHAN BCS 27N
S
Site/Fecal Indicator Bacteria
Conclusions Bolsa ChicaConclusions, Bolsa Chica
• Opening channel did not degrade waterOpening channel did not degrade water quality at adjacent beaches in a one year dry weather study. y y
• Water taken directly from channel has very low concentrations of indicator organisms.g
• Study will be continued one additional year.y
• Effect during rain events is unknown at this time.
Sampling Sites at Huntington State Beach/Newport Beach
Santa Ana River Region Enterococcus Data, All SitesN = 3624
3 00Channel
3.00
PostPre
2.00 104 CFU/100 ml
Log
(ENT
)
1.00
Geomean 8.0 CFU/100 ml
0.00
Date01/0112/0111/0110/0109/0108/0107/0106/0105/0104/0103/0102/0101/01
SAR R i G S l L lSAR Region, Geomean Sample Levels
80
90Geomean
40
50
60
70
U /1
00 m
l
10
20
30
40
CFU
0TC FC Ent TC FC Ent TC FC Ent TC FC Ent TC FC Ent TC FC Ent TC FC Ent TC FC Ent
6N 3N TM 0 SAR-N SAR-S 3S 6S
Sample SiteSa p e S te
SAR Region % Single Sample ExceedancesSAR Region, % Single Sample Exceedances
14.0%
16.0%
8.0%
10.0%
12.0%
ceed
ance
%
2.0%
4.0%
6.0%Exc
0.0%TC FC Ent TC FC Ent TC FC Ent TC FC Ent TC FC Ent TC FC Ent TC FC Ent TC FC Ent
6N 3N TM 0 SAR-N SAR-S 3S 6S
Sample SiteSa p e S te
Comparison of Bolsa Chica and Santa Ana River RegionSingle Sample Exceedances
5%6%7%8%
ance
**
0%1%2%3%4%
Exce
eda
0%TC FC Ent TC FC Ent
Bolsa Chica Santa Ana River
Indicator/Sample Site
* Statistically significant for p < 0.05, by Mann-Whitney U Test
Conclusions Santa Ana RiverConclusions, Santa Ana River
• Channels degrade water quality at downChannels degrade water quality at down current adjacent beaches.
• Water taken directly from channel oftenWater taken directly from channel often has high concentration of indicator organisms.g
• Other studies have shown high levels of enterococcus in channel sediment.
• Dry weather beach failures are correlated with spring tides. p g
Bolsa Chica Wetlands Pollution Factors
Storm Drains: None
Drainage Area: Wetlands only
Intertidal Area: Small but increasing when partial tidal area is opened.
Bird Population: Yes ?Bird Population: Yes ?
Tidal Effect: ?
SAR/Talbert Channels Pollution FactorsStorm Drains: Numerous in both SAR and Talbert Channel (diverted in dry weather)
Drainage Area: Extensive below Prado Dam. Huge total area above dam.
Intertidal Area: Large percentage of wet zone
Bird Population: Yes ?
Tidal effect: Beach pollution occurs during spring tides.
Conclusions• Bolsa Chica is an estuary with a channel that doesn’t
degrade water quality in dry weather. g q y y• Certain factors may determine if an estuary will degrade
surrounding water quality. Connection to storm drains is the main factorthe main factor.
• Routing storm drains through wetlands will possibly pollute the wetlands as well as the receiving water.O /B h t lit t di h ld b t f• Ocean/Beach water quality studies should be part of Bolsa Chica operation.
• Santa Ana River/Talbert Channel is an example of a pwetland/ storm drain system that pollutes adjacent beaches even with diverted storm drains. Cause should be determined through further studies. g