As if home owners didn’t have enough to worry about maintaining their property, more people are finding themselves facing a new enemy: the beaver.

An explosion in the Massachusetts beaver population in recent years, combined with new construction and development in areas previously left alone as wilderness, is leading to more clashes between humans and nature, according to state wildlife officials.

In addition to creating what some see as a nuisance in large pools of water held back by beaver dams, the animals’ work is wreaking havoc on basements and septic systems, possibly diminishing property values and creating a health concern.

“It sounds like a ridiculous subject, until you realize all the damage that it causes,” said attorney Morris N. Robinson of Wellesley. Robinson, who says he is more accustomed to dealing with IRS agents than wildlife issues, found himself in the middle of a beaver dam issue while representing clients in the town of Ayer.

The problem occurred along the Nanacoicus Brook off of West Main Street in town, where he said a number of properties including single-family homes and apartment buildings were being affected by a dam recently put in place by beavers.

“[My clients] are located along the brook, and they noticed the water level rising,” he said. “At that point they decided to investigate and found a beaver dam blocking the flow of water.”

Morrison said property owners and others working with real estate need to learn about what steps to take in the event a beaver decides to build a dam in their vicinity, as trying to restore their land to its original condition could mean serious consequences.

“There are federal laws and state laws … and [Department of] Fisheries and Wildlife policies and Department of Envir-
onmental Protection policies,” he said. “You really have to think through all of your alternatives and try to make sure the proper alternative is chosen.”

Susan Langlois, a wildlife biologist with MassWildlife’s Westborough office, confirmed that reports of clashes between man and beaver are on the rise. “The population has been allowed to grow without any way to control the growth,” she said. “As the population grows exponentially, so do the number of complaints we get about beaver problems.”

One of the main factors behind the increase in the state beaver population was the approval of Question 1 on the November 1996 ballot that prohibited the use of several types of animal traps. Proponents of the question claimed the traps were inhumane, while opponents claimed the ban would allow an unchecked population growth of wild animals. The vote was split: for the most part, urban voters supported the measure while residents of more rural towns voted against it.

“With this type of law, this is what you can expect,” Langlois said. “Right now there’s no harvest on the animal.”

“Before the law, we used to get one beaver call a year,” said Steven Johnson, a wildlife technician with Critter Control of Central Massachusetts in Worcester. “Now during the high- water season, we’ll get six a day.”

Although final estimates on the beaver population for 2000 have not been calculated, Langlois said last year the estimated population was 52,500 beaver, more than twice the 24,000 recorded in 1996.

About 40 percent of the complaints received by MassWildlife involve property flooding Langlois said. Twelve percent of the complaints pertain to roads either washed out or inundated by water diverted because of beaver dams.

Twelve percent of the incidents involve septic system problems. Beaver dams cause underground water levels to rise, Langlois said, which adversely affects leeching fields for some home owners’ septic systems. Furthermore, backed-up water from the dams could also lead to contamination of water wells on the property.

Though there are several problems caused by the beavers’ natural instinct to dam up flowing water, Langlois said there are benefits that need to be looked at as well.

“They can cause a lot of damage, but they also create some of the best wildlife wetland that’s out there,” she said. “It provides some of the best habitat for inland fish and birds and other wildlife. The habitat of a beaver flow is very good to have.”

Permits and Remedies
Trying to reclaim property affected by the beaver dam can be a lengthy process, Langlois said. While MassWildlife can offer advice, because the pond created by the dam is a wetland area any alteration must also be approved by the Department of Environmental Protection.

Remedies include regulated trapping of beaver by a licensed trapper, installation of water control devices installed in the dams to regulate the flow of water, and obtaining a permit to breach a dam to allow the water to flow through. Special permits are usually required. In some cases where a public health hazard is imminent, authorities may allow the animals to be shot.

The biggest obstacle is usually not obtaining permits from authorities, but getting permission to reach the beaver dam itself, Langlois said. “Nine times out of 10 the dam is on someone else’s property and we’re not allowed to trespass,” she said. “The landowner may not have a problem with the beaver dam but it’s affecting people upstream.”

In the case of Robinson’s client, that proved to be less of a problem. “Whenever you’re involved in real estate, you have to be sensitive to the impact on the neighbors. Luckily all of the neighbors were also worried about the water problems so we had no problem getting their approval,” said Robinson, who added that the property owners have just obtained a breach permit.

“If the level could be reduced by two feet, everyone would be happy,” he said. “So we got a breach permit, only it had to be done carefully, because if you don’t follow the rules you’ll probably get a $25,000 fine.”

Langlois said her agency hands out more nominal civil fines for infractions, but added that fines levied by the DEP “can be thousands of dollars.”

“This is a statewide problem,” Robinson said. “It’s more of a problem once you get beyond [Interstate] 495, but now it’s happening even further in.”

Johnson said about 90 percent of his calls are for beaver problems in urban areas, including industrial parks and hospitals in addition to residential areas. “We had a call right near downtown Worcester from a woman with a brook running through her back yard,” he said. “The beaver ended up down here because of development going on upstream that pushed him out. If they can’t be someplace because of development, they’ll find whatever works.”

Langlois said incidents with beavers and humans are becoming more common in areas where previously untouched land is being developed by builders. “In the northeast part of the state, there’s the most population and the most development, so we’re getting a lot of calls from there,” she said. “Wherever the good habitat is, and wherever the most human use is, that’s where the problems are.”

Langlois suggested home builders make some minor modifications in their designs when building homes in anticipation of problems such as those with beaver dams. “When you’re building residential areas, maybe where the grade is five feet up, it should be brought up to 10 feet,” she said. “If they could add that extra element in there, it would help.

“We have to weigh the biological needs of animals versus the cultural needs of people,” she said.