Microbiological monitoring of recreational waters in Santa Monica Bay, California, and the effect... more Microbiological monitoring of recreational waters in Santa Monica Bay, California, and the effects of storm drain effluents on three bacterial indicators. JA LeMay, MS Bartlett, JH Dorsey 1989. As part of the NPDES monitoring ...
Bulletin of the Southern California Academy of Sciences, 1978
A new species of Syllides is described and Amblyosyllis speciosa is recorded for the first time f... more A new species of Syllides is described and Amblyosyllis speciosa is recorded for the first time from California. Both species were taken from shallow rocky areas at San Clemente Island
Bulletin of the Southern California Academy of Sciences, 1995
The City of Los Angeles\u27 Hyperion Treatment Plant presently operates two submarine outfalls: t... more The City of Los Angeles\u27 Hyperion Treatment Plant presently operates two submarine outfalls: the 1-Mile outfall was used until 1959, but now is used only during emergencies; the plant\u27s main outfall, the 5 -Mile, presently discharges about 1,211 X lO^ld \u27 of mixed primary and secondary effluent at a water depth of 60 m. A third outfall, the now defunct 7-Mile sludge line, operated from 1957- 87, discharging about 15 x 10^ 1 d \u27 of digested sludge into 100 m of water at the head of the Santa Monica Canyon. Solids discharged from Hyperion into the Bay have been greatly reduced since the mid-1980\u27s; sludge disposal was termi- nated, and levels of suspended solids in the 5 -Mile effluent diminished from peak levels of 155 mg/L in 1985 to historically low levels averaging around 30 m.g/L in recent years. Analyses often years of semiannual benthic monitoring data demonstrated that assemblages of benthic organisms near the outfalls have shifted in composition from a polluted condition to one more typical of cleaner reference areas. This trend correlated with reductions of solids discharged from the plant. The infaunal assemblage in the old sludge field has changed from a highly degraded to an early transitional assemblage in terms of species composition and abundance, while those near the 5 -Mile outfall have changed from polluted to a more natural assemblage. Continued recovery is expected, but at a slower rate, if the plant maintains its present effluent quality as it moves towards full secondary treatment in 1998
Bulletin of the Southern California Academy of Sciences, 1977
A new species of Rhynchospio is described from shallow subtidal rocky areas at San Clemente Islan... more A new species of Rhynchospio is described from shallow subtidal rocky areas at San Clemente Island. Comparisons are made with related Rhynchospio species
This survey was part of a Binational Program (Mexico-United States) in microbiological water qual... more This survey was part of a Binational Program (Mexico-United States) in microbiological water quality, with a goal to assess the shoreline bacteriological water quality from Tijuana to Ensenada, Mexico. Samples were collected at 29 sites (19 beaches and 10 outfalls), from the United States border to Punta Banda, Baja California, during summer (1998) and winter (1999). Total coliforms, fecal coliforms and enterococci were used as bacterial indicators. Standard methods were used for total and fecal coliforms, while the Enterolert quick method (IDEXX) was used for the enterococci. Compared with outfalls, the beaches exceeded water quality standards by a small percent, 25.3% in summer and 17% in winter. For outfalls, the percentage of shoreline that exceeded bacterial indicator thresholds had a minor value in summer (32.7%) than in winter (50%). Sites near wastewater discharges had the lowest quality and did not meet the microbiological water quality criteria for recreational use.
Two regional studies conducted during dry weather demonstrated that the Southern California Bight... more Two regional studies conducted during dry weather demonstrated that the Southern California Bight (SCB) shoreline has good water quality, except near areas that drain land-based runoff. Here, we repeat those regional studies 36 h after a rainstorm to assess the influence of runoff under high flow conditions. Two hundred and fifty-four shoreline sites between Santa Barbara, California and Ensenada, Mexico were sampled using a stratified-random sampling design with four strata: sandy beaches, rocky shoreline, shoreline adjacent to urban runoff outlets that flow intermittently, and shoreline adjacent to outlets that flow year-round. Each site was sampled for total coliforms, fecal coliforms (or E. coli), and enterococci. Sixty percent of the shoreline failed water quality standards after the storm compared to only 6% during dry weather. Failure of water quality standards increased to more than 90% for shoreline areas adjacent to urban runoff outlets. During dry weather, most water qual...
Screening for the prevalence of antibiotic-resistant bacteria (ARB) was done at the Ballona Creek... more Screening for the prevalence of antibiotic-resistant bacteria (ARB) was done at the Ballona Creek and Wetlands, an urban-impacted wetland system in Los Angeles, California. The goals were (1) to assess the overall prevalence of ARB, and (2) compare differences in ARB abundance and the types of antibiotic resistance (AR) among the following sample types: lagoon water from Del Rey Lagoon, urban runoff from Ballona Creek, and water from the Ballona Wetlands (tidal water flooding in from the adjacent estuary, and ebbing out from the salt marsh). Antibiotic resistance distributions were analyzed using the Kolmogorov-Smirnov test to develop the cumulative frequency of bacteria having resistance of up to eight antibiotics. Distributions from the environmental water samples were compared to unchlorinated secondary effluent from the Hyperion Water Reclamation Plant that was used as comparator samples likely to have an abundance of ARB. As expected, densities of total and ARB were highest in secondary effluent, followed by urban runoff. Samples of water flooding into the wetlands showed similar results to urban runoff; however, a reduction in densities of total and ARB occurred in water ebbing out of the wetlands. During preliminary work to identify ARB species, several bacterial species of relevance to human illness (e.g., Staphylococcus aureus, Enterococcus hirae, Pseudomonas aeruginosa, Aeromonas veronii, Enterobacter cancerogenus, Serratia marcescens, Pseudomonas stutzeri, and Staphylococcus intermedius) were isolated from sampled waters. If wetlands are a sink for ARB, construction and restoration of wetlands can help in the mediation of this human and environmental health concern.
Microbiological monitoring of recreational waters in Santa Monica Bay, California, and the effect... more Microbiological monitoring of recreational waters in Santa Monica Bay, California, and the effects of storm drain effluents on three bacterial indicators. JA LeMay, MS Bartlett, JH Dorsey 1989. As part of the NPDES monitoring ...
Bulletin of the Southern California Academy of Sciences, 1978
A new species of Syllides is described and Amblyosyllis speciosa is recorded for the first time f... more A new species of Syllides is described and Amblyosyllis speciosa is recorded for the first time from California. Both species were taken from shallow rocky areas at San Clemente Island
Bulletin of the Southern California Academy of Sciences, 1995
The City of Los Angeles\u27 Hyperion Treatment Plant presently operates two submarine outfalls: t... more The City of Los Angeles\u27 Hyperion Treatment Plant presently operates two submarine outfalls: the 1-Mile outfall was used until 1959, but now is used only during emergencies; the plant\u27s main outfall, the 5 -Mile, presently discharges about 1,211 X lO^ld \u27 of mixed primary and secondary effluent at a water depth of 60 m. A third outfall, the now defunct 7-Mile sludge line, operated from 1957- 87, discharging about 15 x 10^ 1 d \u27 of digested sludge into 100 m of water at the head of the Santa Monica Canyon. Solids discharged from Hyperion into the Bay have been greatly reduced since the mid-1980\u27s; sludge disposal was termi- nated, and levels of suspended solids in the 5 -Mile effluent diminished from peak levels of 155 mg/L in 1985 to historically low levels averaging around 30 m.g/L in recent years. Analyses often years of semiannual benthic monitoring data demonstrated that assemblages of benthic organisms near the outfalls have shifted in composition from a polluted condition to one more typical of cleaner reference areas. This trend correlated with reductions of solids discharged from the plant. The infaunal assemblage in the old sludge field has changed from a highly degraded to an early transitional assemblage in terms of species composition and abundance, while those near the 5 -Mile outfall have changed from polluted to a more natural assemblage. Continued recovery is expected, but at a slower rate, if the plant maintains its present effluent quality as it moves towards full secondary treatment in 1998
Bulletin of the Southern California Academy of Sciences, 1977
A new species of Rhynchospio is described from shallow subtidal rocky areas at San Clemente Islan... more A new species of Rhynchospio is described from shallow subtidal rocky areas at San Clemente Island. Comparisons are made with related Rhynchospio species
This survey was part of a Binational Program (Mexico-United States) in microbiological water qual... more This survey was part of a Binational Program (Mexico-United States) in microbiological water quality, with a goal to assess the shoreline bacteriological water quality from Tijuana to Ensenada, Mexico. Samples were collected at 29 sites (19 beaches and 10 outfalls), from the United States border to Punta Banda, Baja California, during summer (1998) and winter (1999). Total coliforms, fecal coliforms and enterococci were used as bacterial indicators. Standard methods were used for total and fecal coliforms, while the Enterolert quick method (IDEXX) was used for the enterococci. Compared with outfalls, the beaches exceeded water quality standards by a small percent, 25.3% in summer and 17% in winter. For outfalls, the percentage of shoreline that exceeded bacterial indicator thresholds had a minor value in summer (32.7%) than in winter (50%). Sites near wastewater discharges had the lowest quality and did not meet the microbiological water quality criteria for recreational use.
Two regional studies conducted during dry weather demonstrated that the Southern California Bight... more Two regional studies conducted during dry weather demonstrated that the Southern California Bight (SCB) shoreline has good water quality, except near areas that drain land-based runoff. Here, we repeat those regional studies 36 h after a rainstorm to assess the influence of runoff under high flow conditions. Two hundred and fifty-four shoreline sites between Santa Barbara, California and Ensenada, Mexico were sampled using a stratified-random sampling design with four strata: sandy beaches, rocky shoreline, shoreline adjacent to urban runoff outlets that flow intermittently, and shoreline adjacent to outlets that flow year-round. Each site was sampled for total coliforms, fecal coliforms (or E. coli), and enterococci. Sixty percent of the shoreline failed water quality standards after the storm compared to only 6% during dry weather. Failure of water quality standards increased to more than 90% for shoreline areas adjacent to urban runoff outlets. During dry weather, most water qual...
Screening for the prevalence of antibiotic-resistant bacteria (ARB) was done at the Ballona Creek... more Screening for the prevalence of antibiotic-resistant bacteria (ARB) was done at the Ballona Creek and Wetlands, an urban-impacted wetland system in Los Angeles, California. The goals were (1) to assess the overall prevalence of ARB, and (2) compare differences in ARB abundance and the types of antibiotic resistance (AR) among the following sample types: lagoon water from Del Rey Lagoon, urban runoff from Ballona Creek, and water from the Ballona Wetlands (tidal water flooding in from the adjacent estuary, and ebbing out from the salt marsh). Antibiotic resistance distributions were analyzed using the Kolmogorov-Smirnov test to develop the cumulative frequency of bacteria having resistance of up to eight antibiotics. Distributions from the environmental water samples were compared to unchlorinated secondary effluent from the Hyperion Water Reclamation Plant that was used as comparator samples likely to have an abundance of ARB. As expected, densities of total and ARB were highest in secondary effluent, followed by urban runoff. Samples of water flooding into the wetlands showed similar results to urban runoff; however, a reduction in densities of total and ARB occurred in water ebbing out of the wetlands. During preliminary work to identify ARB species, several bacterial species of relevance to human illness (e.g., Staphylococcus aureus, Enterococcus hirae, Pseudomonas aeruginosa, Aeromonas veronii, Enterobacter cancerogenus, Serratia marcescens, Pseudomonas stutzeri, and Staphylococcus intermedius) were isolated from sampled waters. If wetlands are a sink for ARB, construction and restoration of wetlands can help in the mediation of this human and environmental health concern.
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