Sierra Club: State could have prevented Lake Hopatcong closure

Aerial photo shows algae bloom at Lake Hopatcong, June 2019. Image courtesy of Morris County Freeholders.


From the New Jersey Sierra Club:

Lake Hopatcong Closure Result of Failed Policies

The state Department of Environmental Protection has warned people to stay out of Lake Hopatcong, New Jersey’s largest lake, because of a massive Harmful Algal Bloom (HAB) encompassing most of the lake.

Swimming areas have been closed, and the DEP has urged people not to participate in water sports or have any contact with the water. Phosphorus levels in the lake are the highest in 17 years of data. Other New Jersey swimming areas, including Spruce Run in Hunterdon County, have also been closed recently because of HABs.

“Lake Hopatcong is closed and will be closed for the foreseeable future because of a massive Harmful Algal Bloom (HAB). The lake is headed toward an ecological disaster. The algae blooms produce toxins that endanger people, pets and wildlife, causing severe skin rashes and other illnesses. People can’t swim, and shouldn’t even touch the water. This is a clear sign of failed policies to protect clean water by controlling overdevelopment and stormwater runoff. Lake Hopatcong has become the largest stormwater basin in the state, and the DEP needs to take action,” said Jeff Tittel, director of the New Jersey Sierra Club.

“The July 4 holiday is here, and the largest recreation lake in the state is closed. People can’t go into the lake at all. This is another shameful indicator of our failure to protect our waterways.”

Other lakes across the state have been closed to swimming and water sports, or are under advisories. The Swartswood Lake State Park recently reopened after a Harmful Algal Bloom. Lake Mohawk in Sparta is under an ongoing advisory. Lakes in New York and Pennsylvania have also been closed because of algae blooms.

“DEP’s failure to follow the Clean Water Act has led to the closure of Lake Hopatcong. They have failed at watershed management, managing stormwater, septics and sewers. Overdevelopment has put more houses and septics in the area on every lot, and more fertilizer to be washed into the lake. They have turned Lake Hopatcong into an algae-polluted swamp. The lake is a backup reservoir at the headwaters of the Musconetcong, and it may become a dead body of water,” said Tittel.

“The state came out with TMDLs (Total Maximum Daily Load) for lakes, but they’ve never set proper standards or implemented them. The result is lakes being closed, eutrophying and potentially dying.”

The Lake Hopatcong algae bloom is the result of a combination of warm weather, still water and high levels of nutrients. The recent series of intense storms followed by temperatures 80 degrees and above has washed large amounts of nutrients into the lake and allowed bacteria to thrive.

The phosphorus level in the lake is the highest in 17 years of data. The DEP said it is the largest algae bloom they’ve seen, and could last for months depending on weather conditions.

“Warm weather and high levels of nutrients cause algae blooms to thrive. The bloom in Lake Hopatcong is the largest ever in New Jersey, covering most of the lake. The phosphorus level is the highest ever recorded and could last for months. The phosphorus provides an abundance of food for algae to feed on. The state’s continued encouragement of overdevelopment and sprawl, and its failure to protect our watersheds, is putting more nutrients in the lake.

“No one should have any contact with the water in Lake Hopatcong, including pets. The toxic algae can cause severe rashes and other illnesses. Other lakes and swimming areas are also being closed because of HABs, including the Spruce Run reservoir. Summer is here and we’re running out of places to swim,” said Tittel.

“The pollution in Lake Hopatcong will get worse. People living all around Lake Hopatcong will be unable to use it. The lake will eutrophy and stink as the algae sucks oxygen out of the lake. What’s left will be a giant, stagnant pool of polluted water, creating an environmental and public health disaster.”

Freshwater HABs are caused by bacteria and thrive with high temperature and nutrient levels. They produce toxins that endanger human, pets, livestock and wildlife and can cause allergic skin reactions and other illnesses is swallowed.

People are urged not to have any contact with the water. Fish caught in the lake should not be eaten. The Swartswood Lake State Park swimming area recently reopened after being closed for a HAB. Lake Mohawk in Sparta is under an advisory because of high bacteria levels.

“For years we’ve ignored the problem in Lake Hopatcong. Skimmers have been taking out hundreds and sometimes thousands of tons of weeds and algae every year without dealing with the underlying problems.

“In 2018, nearly 1,800 tons of weeds were harvested, the third highest total since 2002. However the Murphy administration has not rolled back anything to strengthen protections and reduce water pollution. This is failure of government to do its job, enforce the Clean Water Act, and address TMDL, stormwater and septic management. Climate change will only worsen all of these impacts, with higher temperatures and more rain,” said Tittel.

“We usually don’t see HABs like this until August. Lake Hopatcong now has the biggest we’ve ever seen in the state, and July has just started.”

The Murphy Administration has failed to reverse eight years of Christie Administration rollbacks on waterways that have led to increased pollution and overdevelopment. Those rollbacks weakened protections for stormwater, allowed development in environmentally sensitive areas that impacts water quality, and reduced protections for streams and stream buffers.

“The state needs to move forward with watershed protections. We need to establish stream buffers and enforce real TMDL standards in our lakes. We need to toughen rules on stormwater management and bring back Septic Management Districts. We need to reduce overdevelopment and sprawl in environmentally sensitive areas. Otherwise the pollution will only get worse.

“Conditions at Lake Hopatcong will deteriorate, and other lakes will be shut down for extended periods as well. New Jersey doesn’t have enough public swimming areas as it is, and now more and more of them are closing because of algae blooms.

“As the weather gets hotter, we are only going to see more beaches and swimming areas becoming too dangerous to use,” said Tittel. “The state needs to take immediate action to reduce pollution into our lakes and waterways.”

[interactive_copyright_notice float='left']
[icopyright_horizontal_toolbar float='right']


  1. I spend the first 30 years of my life on Lake Hopatcong during the summer months. The issue of septic systems of lake front houses was a problem back in the 1970s. One of my friend did his master’s paper on lake front septic systems and he found that over 50% leaked directly in the lake. I knew of two lake front houses, back in 1971, in which you could see and smell the septic waste…..
    The cause is simple, Lake Hopatcong was originally a summer home area and the septic systems were just one or two 55 gallon containers and a drainage field. This was good for only weekend use.
    However back in the 1950s and 1960s people move their homes to year round. But never upgraded the septic field. Therefore the drainage field quickly overflow and into the lake. This leakages into the lake continues to this day.
    I now live in Minnesota, lake front houses as they are sold must change to a totally closed systems that must be pumped out – no drainage into the lake.
    There are reasons why people are still leaving New Jersey faster than coming to live…..

  2. What part of the current problem can be attributed to the abuse of the lake by boaters who spend entire weekends anchored in some of the coves? Since heads (toilets) are sealed on these boats, where do you suppose these families relieve themselves over the weekend? This, along with the noise and congestion caused by these lashed together boats has been a problem for years. Since over abundance of nutrients is fueling the algae problem, isn’t this abuse of the lake contributing to it by providing lots of nutrients loaded with phosphorus?

  3. This could have been prevented if a number of things had happened: 1) state, county and municipalities around the lake put sewers in when federal money was available in the 1960s and 1970s and sewer charges could still be incorporated into property taxes (making them partially tax deductible), 2) had permits not been granted to convert seasonal homes to year-round use without requiring them to either connect to sewers or install up-to-date septic systems (many homes still have cesspools) 3) fertilizer rules should have been strengthened years ago prohibiting phosphorus containing lawn fertilizers and limiting application of all fertilizers when rain is forecast and also limiting the “strength” of the fertilizers (I believe phosphorus is the “limiting” nutrient–the nutrient that, without being added to water bodies, is not available in excess) 4) lakefront properties probably ought to be required to have only native plantings that do not need fertilizer and regular lawns should not be permitted.
    All of these things should have been done decades ago, some could be done now such as better regulating fertilizer. Also, the stormwater regulations pilloried by Republicans as a “rain tax” may help divert runoff from the lake but what else can be done to reverse the decline?

  4. This Lake needs to have It’s many coves dreaged .to much muck is the real cause and it’s just from leaves and weed’s decaying.