Introduction

Analysis of Sand Samples from the Sand Island Sewer Outfall, Mamala Bay, O’ahu (Interim Progress Report)

Analysis of Sand Samples from the Sand Island Sewer Outfall, Mamala Bay, O’ahu (Interim Progress Report)

Technical Memorandum Report No. 60
Analysis of Sand Samples from the Sand Island Sewer Outfall, Mamala Bay, O’ahu (Interim Progress Report)

S. Arthur Reed
May 1978

ABSTRACT
Sand grab samples were collected from nine locations at and around existing and proposed ocean sewage outfalls and at a control station. The preserved samples were analyzed for abundance of invertebrates. Stations in the vicinity Of the existing outfall (12 m deep) were characterized by high abundance of annelid tube worms which grew in huge, densely packed . clusters. Foraminifera and the green algae Halimeda sp. were absent or in relatively low abundance. In the vicinity of the proposed outfall (65 m deep) samples contained high abundance of Halimeda sp., moderate quantities of Foraminifera, and the solitary coral Fungia fragilis; no annelid worms were found. This pattern of abundance was similar to the control station. The pen shell Pinna semicostata was present at most deep water stations. Extensive beds of this mollusk are common in other regions along south O¹ahu.