A hydrographic survey team is mapping the bottom of a deep coastal harbor using a single-beam echo sounder. During the survey, the team observes two distinct anomalies in the data:

Explain the cause of each anomaly and recommend a corrective procedure.

A hydrographic survey vessel maps a shallow channel leading into a port. They record a raw depth sounding of 12.5 meters using an echo sounder. However, the survey was conducted at 2:00 PM, which corresponds to High Tide. The tide gauge at the port shows the water level was 2.0 meters above the Mean Lower Low Water (MLLW) chart datum at that exact time.

Explain why the raw sounding cannot be printed on the nautical chart, and calculate the corrected chart depth.

An echo sounder installed on a survey vessel emits an acoustic pulse and receives the echo from the seabed $0.065 \text{ seconds}$ later. The average velocity of sound in the seawater at this location was determined by an SVP to be $1520 \text{ m/s}$. The draft of the vessel (the depth of the echo sounder transducer below the water surface) is $1.2 \text{ m}$.

Calculate the true depth of the seabed below the water surface.

A survey vessel takes simultaneous sextant readings on three known onshore control points (A, B, and C) to fix its position (Point V). The coordinates of the control points are:

The vessel observes the horizontal angle between A and B ($\alpha$) as $45^\circ$ and the horizontal angle between B and C ($\beta$) as $45^\circ$.

Using the principles of the Three-Point Problem (Resection), determine the approximate location of the vessel (X, Y coordinates).

To measure the discharge of a stream, a surveyor divides the stream cross-section into three vertical segments. The width ($W$), average depth ($D$), and average velocity ($V$) for each segment are measured as follows:

Calculate the total discharge (flow rate) of the stream in cubic meters per second ($m^3/s$).

The area of water surface within contour lines of a proposed reservoir is measured by a planimeter as follows:

Calculate the total capacity (volume) of the reservoir between elevations $100 \text{ m}$ and $115 \text{ m}$ using the Prismoidal Formula.