Farm Pond: What was the difference?

Surface area

The farm pond as first excavated had a surface area of about 11,000 square-feet or 1/4 acre.

The farm pond specified in the contract was supposed to have a surface area of 22,000 square-feet or 1/2 acre or TWICE as large in area as what was delivered.

Weed-free area

Curlyleaf Pondweed (Potamogeton crispus)

As a rule-of-thumb, submerged vegetation does not break the surface when the bottom is 6' or more below the surface of the water.

It is not fun to swim when seaweed wraps around your legs.

The area of the pond as first excavated where the bottom was 6' or more below the surface was essentially zero. For most pond owners, that means that the pond as first excavated would have no usable area after June 15 (in Michigan) for boating, swimming or fishing. It would also be subject to winter die-off due to excessive vegetation dying and decaying which would gobble up all of the oxygen dissolved in the water.

The area of the pond specified in the contract would have approximately 10,000 square-feet where the bottom was 6' or more below the surface. The "weeds" would only extend from the shoreline to 18' out. In fact, the area of usable pond that would be deeper than 6' would be almost as large as the entire pond as-built.

Volume of pond

The volume of the pond is a first-order approximation of the amount of fill that had to be moved and is directly related to the contractor's cost to dig the pond.

The pond as first excavated displaced about 940 cubic-yards.

The pond as specified in the contract would have displaced about 3200 cubic-yards.

In other words, the contractor's cost to dig and move the fill was understated by a factor of three relative to what an "honest" quote would have been based on. 

The comparisons underestimate the costs because more fill that is removed must be carted farther away from the nominal water's edge. 

Summary:

• Half the surface area the contract called for
• One third the volume (assuming a maximum depth of 12' and 1:3 slope)
• A million times less weed-free area and a similar disadvantage in terms of winter fish-kill

Yeah, my buddy had every right to go after them. What he paid for would have been an asset. What the contractor delivered was a liability.