Probably the most reliable and least expensive way to eliminate carp would be to drain the pond. I believe if the pond is less than one acre, a drawdown permit from PFBC and DEP (free) is not required. Caution needs to be used so it doesn't drain too fast not only to minimize erosion of the stream below but also to avoid sloughing off of water soaked steep banks around the pond. Downstream neighbors may not be too happy with stranded, dead and dying fish including carp.

The Commission doesn't get involved in salvage operations but a local angling club might for stocking a community pond (yes, even with carp). You might want to drain it say late Fall once air temperatures decrease to minimize the odor problem which often accompanies not only dead fish but also the much and decaying aquatic vegetation common to a drained pond. Allowing it to stay drained for awhile will assure a complete kill including those "hidden" in the mud. If the pond is going to be down for an extended period of time, I also suggest sowing some inexpensive grass seed around to establish a ground cover to minimize erosion and to reduce the eye sore. Another benefit of draining the pond lies in re-stocking it with the fish appropriate with the type of angling your friend desires. Suggestion: keep the new community simple. The smaller the pond the simpler the mix of species.

One might also use chemical reclamation if dewatering is not possible. Regardless of the fact your friend owns the pond and even the outlet stream, use of chemicals (aquatic herbicides, algacides, and compounds intended to kill fish, etc) requires a permit (free). Remember, said water will flow elsewhere and the permitting process protects downstream users and environments. Chemicals can be quite expensive and are usually not species selective. In other words, to eliminate carp usually means killing off everything.

Seining/electro-fishing operations, while likely to take a goodly number of carp, are also likely to miss some fish unless the pond is very small, very shallow, void of stumps-weeds, etc. I suggest if these techniques are desired, your friend should hire the services of an aquatic consultant. Then, the matter of permits and related issued can be handled by people who do this sort of thing for a living. While electro-fishing gear might be available on a rental basis, I do NOT recommend amateurs do it, as such has the potential for killing people in addition to being an illegal device unless covered by a permit. The fact that a highly proficient crew is likely to miss some carp, I might think twice before investing money in netting or electro-fishing.

One might consider making the best of a bad situation and fishing out the carp. This may rub the pond owner the wrong way, but at least he could enjoy this resource. It is very doubtful angling would result in elimination.

One might even stock predators such as the tiger muskellunge (hybrid cross between a northern pike and muskellunge) or muskellunge to prey on the carp. Even then it would take some time before any impact might be noted and existing large carp too large to be eaten might still outlive the toothy predators.

Wish I had a surefire and inexpensive suggestion for your friend. We have abundant carp in some of our lakes but then the larger the system the less impact one species has.

Whatever your friend does, should he be successful in eliminating carp he might want to think about restricting the use of live fish as bait to prevent someone from introducing young carp back into the pond.