As part of a pipeline project design and development a study to estimate the peak flood and peak ebb bottom currents at prescribed sites along a pipeline route, as well as an extremal analysis to determine potential maximum bottom currents for various return period storms. The analysis used hydrodynamic model predictions, local current station observations and the long-term hurricane (storm) record in the area to develop the extreme value analysis (EVA).
A similar analysis was performed to assess the wave climate along the pipeline route in addition to the currents. Period of record wind data from local airport and NDBC buoy stations, which also had wave data were collected along with publicly available model based long-term reanalysis data sets to develop a comprehensive metocean data set for use in the EVA along with the 50-year storm record for the area. To develop high resolution local wave induced bottom current predictions along the pipeline, a wave model was applied to the area using the wind and wave reanalysis data for boundary conditions. The buoy data was used to validate the wave model forcing and a long-term simulation was run collecting data at representative pipeline sites for which the EVA was then performed.
An oil and gas company was developing a deepwater gas field discovery offshore of the town of Palma in the Cabo Delgado Province, Mozambique. The development in the Prosperidade area was to consist of wells connected to a subsea or floating production facility, product export pipelines, and an onshore plant. Anadarko had implemented a 3 year field observation program consisting of a series of offshore and nearshore mooring deployments, tide stations, and meteorological towers to characterize the met-ocean environment in the area. The program collected wind, wave, tidal, current, salinity, and temperature data at 16 sites across the area beginning in 2011.
In preparation for the development, a detailed review and characterization of metocean conditions, including an extremal analyses to assist in the development of facility and pipeline critical design criteria and to assess potential constraints on operational activities in the area, in addition to a correlational analysis on the data collected was performed.