Our pond has 1000+ miles of shoreline, so (as usual) I'm not much help. The Corp of Engineers has some pretty strict guidelines but nothing unreasonable. Follow the rules, apply for permits and enjoy. I'd be surprised if the COE has jurisdiction over a 1 acre pond but worth checking on as previously mentioned.

http://forums.pelicanparts.com/uploa...1511357970.jpg

The Corps regulations broadly define two important terms, “waters of the United States” for the purpose of Section 404 of the Clean Water Act; and “navigable waters of the United States” for Section 10 of the Rivers and Harbors Act.

Waters of the United States

The definition of “waters of the United States” includes the following:

a. Navigable waters of the United States.
b. Wetlands.
c. Tributaries to navigable waters of the United States, including adjacent wetlands and lakes and
ponds.
d. Interstate waters and their tributaries, including adjacent wetlands.
e. All other waters of the United States not identified above, such as isolated wetlands,
intermittent streams, and other waters that are not part of a tributary system to interstate waters or to navigable waters of the United States, where the use, degradation or destruction of these waters could affect interstate or foreign commerce.

Section 404 of the Clean Water Act defines the landward limit of jurisdiction as the high tide line in tidal waters and the ordinary high water mark as the limit in non-tidal waters. When adjacent wetlands are present, the limit of jurisdiction extends to the limit of the wetland.

http://www.nae.usace.army.mil/Portals/74/docs/regulatory/JurisdictionalLimits/Jurisdictional_Limits_Brochure.pdf

The one acre thing usually comes into play with regards to the need for a storm water pollution prevention plan (SWPPP).

https://www.epa.gov/npdes/stormwater-discharges-construction-activities

From what I can tell the Army Corps is concerned about changes to flowing water and wetlands. I have not yet visited the property, but from aerial photos the pond appears to be natural and spring fed.