"Cdon" wrote in message
oups.com...
Where do I find a private property dam inspector in NJ?

There is land I'm interested in purchasing near Morristown New Jersey
which has a tiny 100 foot diameter 10'foot deep pond with a ten foot
tall embankment and a 1-foot diameter pipe about 5 feet long going thru
that bank to the next property.

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Some comments --

A hydraulic engineer is a specialized civil engineer. That is what I was
before my retirement some years ago. I will provide some comments in no
particular order.

1. I doubt that pipe through a 10' embankment is only 5' long. I will
assume
it is much longer.

2. The surface area of the pond is about one-fifth of an acre. Assuming an
average depth of 5', a failure of the embankment could flood an acre of land
only 1' deep. Unless there are significant structures, houses, etc.,
downstream, the risks are pretty small.

3. One of the two principal failure modes for earthen dams is seepage under
the embankment. Consider the number of years it has been in place. These
failures usually show up shortly after the water is impounded. To inspect
for problems, you look for damp soil or flowing springs below the dam.
Small flows of *clear water* generally indicate a stable (safe) condition.
Muddy flows indicate active erosion of the substrate of the dam and
potential failure.

4. The other principal failure mode is spillway inadequacy. A spillway is
usually provided to bypass sudden storm inflows that are too large for the
normal outlet (that 1' pipe). It may be as simple as a sodded channel
around the end of the embankment. Without a spillway, water might overflow
the embankment causing a sudden spill of the water in the pond.

5. There are thousands of such small dams and ponds around the country.
Many have been designed by the Soil Conservation Service of the U. S.
Department of Agriculture. They usually are of simple design appropriate to
their use and locale. The local office may (or may not) be able to help in
evaluating the design of the outlet and spillway.

6. Some states require a permit before constructing such a pond. If so,
there may be construction drawings on file. It is very likely that a search
will show that the structure was never registered and you may be required to
do that after the fact.

7. It seems you may be overly concerned for the soundness of this small
structure. But -- and a big "but" -- I know nothing of the area downstream
from the structure and I know nothing of the neighbors who may have a
concern. If there is a real concern about the structure, it would be a
simple matter to cut a trench through the embankment and let the pond drain.

SJF