Dredging began in Te Awanui/Tauranga Harbour, the largest port in Aotearoa New Zealand, in 1919 to allow continued development of the port. The dredged material gets disposed of by depositing it into open water in a process known as spoiling. It is more important than ever to understand the impact of dredging as ships are getting ever larger, which require deeper and wider channels for safe passage into ports. This thesis investigated the composition and distribution of the dredge spoil on the Bay of Plenty inner shelf for the first time since 1992. Between August 2023 and February 2024, I used seismic and sedimentological analyses, including shallow seismic surveys, vibracoring, and surficial sediment sampling to determine the size and shape, and the grain size and organic content comprising the dredge spoil mound. Results showed that the sediments are predominantly fine to medium-grained moderately sorted sand with low organic content. The dredge spoil mound sits on average 1.5 m above the pre-deposition seafloor, and has no discernible surface texture or bedforms. This study establishes that the composition of the dredged sediment remains comparable to that of the pre-deposition seafloor. The results are compatible with past studies, suggesting that dredge spoil deposited on the inner shelf is stable, and is not subject to resuspension and transport under fair weather conditions.