The RAINIER and her launches acquire soundings throughout the day at all stages of tide. Vertical corrections must be made to this data such that soundings meet NOAA's nautical charting datum of Mean Lower Low Water (MLLW). The RAINIER uses tidal data to correct soundings to MLLW. The tidal data is obtained from local primary control stations of the National Water Level Observation Network. Since some of these stations are far from the project area, the RAINIER also sets up tertiary tide stations to obtain more accurate local data.

A tide station is set up prior to acquiring soundings. More than one station may be set up depending on the project area. A tide station crew consists of at least six people: two to set up land-based equipment, two divers to install a bubbler orifice, one to drive the launch that carries equipment, and one to drive the skiff for shore and diver assistance.

The equipment involved in an installation is extensive. Dive gear is needed to establish the orifice. A staff is installed for taking visual tidal observations. A tide gauge is used to collect data. Benchmarks and leveling equipment are used to establish elevations of the site.

NOAA's Center for Operational Oceanographic Products and Services offers a detailed description of how and why a tide station is installed.

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NOS benchmarks are installed for leveling purposes at tide stations.	Divers assist with many aspects of tide station instillations.	ENS McGovern assists with the leveling process.
A leveling survey is performed to establish and verify station elevations.	LTJG Hauser downloads data from a tide gauge.