Roi-Namur is located at the northernmost tip of Kwajalein Atoll, approximately 64 kilometers north of the U.S. Army Kwajalein Atoll (USAKA) central command post on Kwajalein Islet. Roi-Namur has a single sewage outfall, which is located at the northwestern corner of the islet. Originally, the outfall extended from shore to a point about halfway across the reef flat where the pipe ended abruptly as an upturned, uncapped elbow. Raw sewage was pumped through the pipe in pulses approximately every 15-20 minutes. Waves and shallow currents across the reef flat carried at least some of the effluent back toward shore and the lagoon, creating a potentially unhealthy situation. In order to correct this problem, USAKA implemented a plan to extend the original outfall all the way across the reef flat and into the open ocean where the predominant current flow would carry effluent-mixed waters away from the islet. Ultimately, the extended outfall was to be connected to a new sewage treatment facility that would discharge primarily treated effluent. Because of a concern that this discharge might adversely impact the coral-reef community surrounding the end of the new outfall, a baseline marine biological survey was to be conducted prior to start-up of the new sewage treatment facility. As planned, the results of this survey would provide a baseline against which the results of future surveys could be compared in order to determine whether a balanced community of indigenous species had been maintained at the site during operation of the facility. If not, conversion to secondary treatment at the facility would need to be considered. The first resurvey was planned to occur one year after start-up of the new sewage treatment facility with subsequent resurveys planned for every five years thereafter. In August 1997, biologists from the U.S. Fish and Wildlife Service (USFWS) and the National Marine Fisheries Service (NMFS) conducted the baseline marine biological survey in the vicinity of the Roi-Namur outfall. In May 2000, biologists from these agencies returned to Roi-Namur to re-characterize the coral-reef habitat and biological organisms at five survey sites in the vicinity of the outfall, previously established during the 1997 baseline marine biological survey. The purpose of the second survey was to collect data to determine whether a balanced community of indigenous species had been maintained at this location after the sewage treatment facility became operational. If not, conversion to secondary treatment at the facility would need to be considered. For the National Oceanographic Data Center, interest in the report focuses on the marine element. Data tables from marine surveys of reef fishes, corals, other macroinvertebrates, and algae that exist in those habitats are provided.

Roi-Namur is located at the northernmost tip of Kwajalein Atoll, approximately 64 kilometers north of the U.S. Army Kwajalein Atoll (USAKA) central command post on Kwajalein Islet. Roi-Namur has a single sewage outfall, which is located at the northwestern corner of the islet. Originally, the outfall extended from shore to a point about halfway across the reef flat where the pipe ended abruptly as an upturned, uncapped elbow. Raw sewage was pumped through the pipe in pulses approximately every 15-20 minutes. Waves and shallow currents across the reef flat carried at least some of the effluent back toward shore and the lagoon, creating a potentially unhealthy situation. In order to correct this problem, USAKA implemented a plan to extend the original outfall all the way across the reef flat and into the open ocean where the predominant current flow would carry effluent-mixed waters away from the islet. Ultimately, the extended outfall was to be connected to a new sewage treatment facility that would discharge primarily treated effluent. Because of a concern that this discharge might adversely impact the coral-reef community surrounding the end of the new outfall, a baseline marine biological survey was to be conducted prior to start-up of the new sewage treatment facility. As planned, the results of this survey would provide a baseline against which the results of future surveys could be compared in order to determine whether a balanced community of indigenous species had been maintained at the site during operation of the facility. If not, conversion to secondary treatment at the facility would need to be considered. The first resurvey was planned to occur one year after start-up of the new sewage treatment facility with subsequent resurveys planned for every five years thereafter. In August 1997, biologists from the U.S. Fish and Wildlife Service (USFWS) and the National Marine Fisheries Service (NMFS) conducted the baseline marine biological survey in the vicinity of the Roi-Namur outfall. For the National Oceanographic Data Center, interest in the report focuses on the marine element. Data tables from marine surveys of reef fishes, corals, other macroinvertebrates, and algae that exist in those habitats are provided.

Roi-Namur is located at the northernmost tip of Kwajalein Atoll, approximately 64 kilometers north of the U.S. Army Kwajalein Atoll (USAKA) central command post on Kwajalein Islet. Roi-Namur has a single sewage outfall, which is located at the northwestern corner of the islet. Originally, the outfall extended from shore to a point about halfway across the reef flat where the pipe ended abruptly as an upturned, uncapped elbow. Raw sewage was pumped through the pipe in pulses approximately every 15-20 minutes. Waves and shallow currents across the reef flat carried at least some of the effluent back toward shore and the lagoon, creating a potentially unhealthy situation. In order to correct this problem, USAKA implemented a plan to extend the original outfall all the way across the reef flat and into the open ocean where the predominant current flow would carry effluent-mixed waters away from the islet. Ultimately, the extended outfall was to be connected to a new sewage treatment facility that would discharge primarily treated effluent. Because of a concern that this discharge might adversely impact the coral-reef community surrounding the end of the new outfall, a baseline marine biological survey was to be conducted prior to start-up of the new sewage treatment facility. As planned, the results of this survey would provide a baseline against which the results of future surveys could be compared in order to determine whether a balanced community of indigenous species had been maintained at the site during operation of the facility. If not, conversion to secondary treatment at the facility would need to be considered. The first resurvey was planned to occur one year after start-up of the new sewage treatment facility with subsequent resurveys planned for every five years thereafter. In August 1997, biologists from the U.S. Fish and Wildlife Service (USFWS) and the National Marine Fisheries Service (NMFS) conducted the baseline marine biological survey in the vicinity of the Roi-Namur outfall. For the National Oceanographic Data Center, interest in the report focuses on the marine element. Data tables from marine surveys of reef fishes, corals, other macroinvertebrates, and algae that exist in those habitats are provided.

During 1990-1999, coral growth and fish abundance were monitored at stations located at and in the vicinity of the Waianae Ocean Outfall. Comparisons of results with fish surveys showed no significant differences in the species composition or relative abundances of fish populations at Station W-2 (the sunken ship Mahi), which is located 1.2 km south of the diffuser. Fish abundance and species richness increased at Station W- 3, which is located at the diffuser, from 1990 to 1995, decreased in 1996, and increased again in 1997 through 1999. At Station WW, an inshore station located 0.8 km from shore, fish were abundant and speciose on the armor rock covering the pipeline. The fish species seen inshore are comparable to fish species seen in similar (boulder) natural biotopes around Hawaii. There were no significant differences in total mean coral cover at selected quadrats from 1994 to 1999 at Station W-2. However, there was a significant increase (approximately 8%) in total mean coral cover at this station from 1991 to 1999. At the diffuser, corals were seen growing on the diffuser pipe and on the riser discharge ports. In 1986, when the diffuser began operation at a discharge rate of 1.5 mgd (0.07 m3/s), no corals were seen at this location. At inshore station WW, corals off the pipeline were sparsely distributed but were numerous and thriving on the armor rock over the pipeline. In 1998 the inshore transect (Alpha), off the armor rock, was covered (30%) with the alga Dictyopteris plagiogramma; however, in 1999 it disappeared. This seaweed was also abundant at this location in 1995, 1996, and 1997. The water was clear at all stations surveyed (13 to 20 m horizontal visibility), and the surrounding sediments were clean and white. No significant deleterious effect due to outfall operation and discharge were seen on the biological community at the stations surveyed. The increase in fish diversity and abundance at the diffuser since 1997 may be due to natural fluctuations in abundance or to environmental conditions suitable to the fish populations living there.

The U.S. Army Space and Missile Defense Command (SMDC), in support of the Ballistic Missile Defense Organization (BMDO) sponsored a marine biological survey at Wake Atoll, located approximately 2,100 miles west of Honolulu at 19 deg 18 min North Latitude and 166 deg 35 min East Longitude. On behalf of the SMDC, biologists from the U.S. Fish and Wildlife Service (USFWS) and the National Marine Fisheries Service (NMFS) were invited to Wake Atoll in June 1998. The purpose of the visit was to conduct baseline marine biological surveys in the vicinity of the Peacock Point outfall pipe and to examine the sites of other point-source discharges to the marine environment (i.e., power plant, desalinization plant, and stormwater outlets). The biologists were asked to (1) generally characterize the coral-reef habitats within the vicinity of the outfall, (2) document the primary species of reef fishes, corals, other macroinvertebrates, and algae that exist in those habitats, and (3) investigate whether the reef communities at the other sites appeared to have been impacted by the discharges.

A survey of the marine communities of Midway Atoll harbor and surrounding lagoon was conducted at 12 sites from September 5 to 9, 1998. The primary focus of these surveys was the invertebrates of the fouling communities present on artificial substrates. Occurrence of reef fishes at each site was also recorded, and algae was collected and identified from four stations. A total of 444 taxa were identified (47 algae, 316 invertebrates, and 81 fishes) from all stations. Approximately 250 invertebrate and 35 algae species are considered new records for Midway Atoll. All fishes observed were previously recorded from the atoll. Only three invertebrates identified in this survey are considered to be nonindigenous species in the Hawaiian Islands. One introduced bryozoan, Amathia distans, dominated the fouling communities at most stations where artificial substrates were available. Another introduced bryozoan, Schizoporella errata, was also common at the same stations. A non indigenous barnacle, Chthamalus proteus, recently introduced from the Caribbean, was common on pier pilings inside Midway harbor. No introduced invertebrates were present in natural habitats. The introduced snapper, Lutjanus kasmira, was also present along the reef outside the lagoon. The threat to the native reef community by established non-indigenous species is considered minimal. The presence of these introduced species at Midway, especially Chthamalus proteus, suggests that vectors of future, potentially more deleterious introductions exist. Transport of these introductions was most likely as fouling on ship bottoms, but other sources of introductions, such as ballast water carried in ships, should be guarded against to protect the relatively pristine reefs of Midway Atoll.

This report provides the results of the first quantitative survey of the coral reef communities in the vicinity of the Mokapu Ocean Outfall in Kailua Bay, Oahu, Hawaii. This survey, conducted in April and July 1998, focuses on benthic and fish community structure and is designed to detect community changes that may be mediated by the release of treated sewage through the outfall. The Kailua Regional Wastewater Treatment Plant (WWTP), which has been operational since 1977, releases a little more than 13 mgd of secondary treated sewage through a 1.55-km-long discharge pipe at a depth of 32 m. If impacts are occurring to marine communities from a point-source discharge, their effects will be most evident in proximity to the source and less obvious with distance from the source. The sampling strategy used in this study focuses on quantifying the degree of development of marine communities adjacent to and at distances from the discharge source. This strategy should allow delineation of impacts if they are occurring. The results of this first survey indicate that the marine communities in the study area are diverse, with well-developed fish and coral components. This is particularly evident on the Mokapu Ocean Outfall diffuser (Transect T-1) where a high-biomass, diverse fish community occurs. This well-developed fish community is related to the shelter created by the diffuser pipe and basalt armor rock, as well as to the release of organic particles in the treated effluent which serve as a food resource for some fish species. The development of corals as measured in terms of live coverage in the diffuser pipe community is about half that found at the more distant sampling sites. However, a second sampling site (Transect T-2) located parallel to and 15 m away from the diffuser has coral coverage very similar to that found elsewhere in Kailua Bay. These data suggest that if the operation of the Kailua Regional WWTP is having an impact on marine communities, it is very limited in scope and scale.