This experiment tested the effects of secondary treated sewage effluent on infauna assemblages that were taken from a 'reference' site immediately after a large dump of macroalgae had cleared from the mudflat. Macroalgae cover can have severe effects on infaunal assemblages so it was expected that the recent macroalgae dump would affect the responses of infauna to the effluent dosing. Twelve intact sediment cores were collected from this site on the Western Treatment Plant foreshore (Port Phillip Bay, Victoria) and brought back to the laboratory. Four cores were assigned to each of the two treatments, which were high dose (7mls effluent per minute) or no dose of effluent. The experiment ran for 13 days in October 1999. Throughout the experimental period, dissolved oxygen levels were measured and animals that migrated from the sediment were collected, counted and identified. At the end of the experiment, sediment chlorophyll levels were measured and infauna remaining in the sediment were counted and identified.

This experiment tested the effects of secondary treated sewage effluent on infaunal assemblages that were collected 50m from a sewage outfall ('outfall' assemblage). Twelve intact sediment cores were collected from this site on the Western Treatment Plant foreshore (Port Phillip Bay, Victoria) and brought back to the laboratory. Four cores were assigned to each of three treatments, which were no dose of effluent, high dose (7mls effluent per minute) or a 'no escape' treatment. The experiment ran for 13 days in December 1999. Throughout the experimental period, dissolved oxygen levels were measured and animals that migrated from the sediment were collected, counted and identified. At the end of the experiment, infauna remaining in the sediment were counted and identified and the wet weight biomass of each species group was recorded.

This experiment tested the effects of liquid effluents on infauna assemblages in the presence and absence of shorebirds. Small plots of sediment (70cm x 50cm) were dosed with sewage effluent, freshwater, seawater or control ('no dose') and were either open or closed to shorebird predation. The plots were set up in early summer 2000 with replicates of each combination of factors at 4 levels on the shore. Plots were sampled at 0, 4 and 6 weeks for infaunal abundances and biomass and surface sediment chlorophyll a levels.

This review was a synthesis of studies that monitored the effects of sewage disposal in the marine environment. Twenty studies that were conducted between 1973 and 1997 and met specific design requirements (i.e. no confounding factors, appropriate replication) were included in the review. Background data relating to discharge type, quantity, level of detail and sampling procedures of the investigation in each study were collated. Any impact that was detected was recorded for each endpoint. The magnitude of change or effect size was calculated for each study and was defined as the percent change at the impact site relative to the control sites. There were some consistencies in the monitoring strategies and benthic responses between studies in different areas. Multivariate indicators and population level analyses were the most sensitive measures for detecting sewage related impacts. Abundance usually increased at outfall sites relative to controls (30-250% magnitude of change) while species richness, diversity and evenness tended to decrease (16-90% magnitude of change). The geographic extent of the studies were limited to temperate regions except for 1 study that was conducted in Antarctica.

Metadata record for data expected from ASAC Project 996 See the link below for public details on this project. The study investigated the effects of the small sewage outfall on algal epifauna in the isthmus area. No impacts were detected and patterns of community structure were tentatively explained by local differences in wave exposure gradients. From the abstract to the referenced paper: As part of a wider programme investigating the effects of human presence on Antarctic and sub-Antarctic ecosystems, this study evaluated the impact of the small sewage outfall at Macquarie Island on the epifauna living within turfs of the intertidal red alga Chaetangium fastigiatum. Sampling was conducted during early December (austral summer) in both 1996 and 1997 at six sites, two sites within each of three adjacent bays. The site closest to the outfall was 3m from the point of discharge. Data analyses at the population and community levels failed to demonstrate a significant effect of the outfall. Small scale spatial patterns, probably related to wave exposure, and inter-annual variation in recruitment, are suggested as the main causes of variation in patterns of epifaunal dominance during the study. The site codes used in this dataset are: GCS - Garden Cove South GCN - Garden Cove North GBS - Bay 1 South GBN - Bay 1 North CS - Bay 2 North CN - Bay 2 South At each site 5 replicates were taken. The numbers are total individuals of each species that were found in each Chaetangium sample. This is a basic, though standard, species-abundance matrix. The fields in this dataset are: Species Site Year