Maryland Democratic gubernatorial candidate Lt. Gov. Anthony Brown, left, and Republican candidate Larry Hogan at a debate Oct. 18 at Maryland Public Television’s Owings Mills studio. (Patrick Semansky/Associated Press)

The two men competing to become Maryland governor have starkly different views on key environmental issues in a state that is weighing fracking and wind farm projects and an off-shore natural gas pipeline, and where costly efforts to restore the Chesapeake Bay have generated heated debate.

Lt. Gov. Anthony G. Brown, the Democratic nominee, says he will continue to embrace the $15 billion plan put in place by Gov. Martin O’Malley (D) to restore the bay’s health by 2025.

The plan calls for upgrading urban sewers that spew millions of gallons of raw sewage into the bay each time it rains, and for making sure that farmers reduce the tons of animal manure and fertilizer that flow into the bay every year.

“I stand in the tradition of Marylanders who feel we have a responsibility to protect the environment and the bay,” Brown said, calling the estuary the “cornerstone of our economy.”

Republican Larry Hogan, in contrast, has said that the bay cleanup is a major waste of money because Maryland cannot control polluted sediment that flows from New York and through Pennsylvania through the Susquehanna River. A reservoir of sediment rests behind the Conowingo Dam, where the Susquehanna extends into Maryland. Tons of sediment slosh over the dam and into the bay, polluting it.

A look at the two candidates and their views on some of the most pressing issues in the 2014 Maryland governors race.

Hogan did not respond to requests for an interview for this article. But he has based much of his gubernatorial campaign on rolling back tax increases passed during Brown’s time as lieutenant governor. One of the most hated taxes is the one critics have derisively dubbed the “rain tax,” a stormwater management fee that is supposed to fund improvements in the way that stormwater moves through each Maryland jurisdiction.

Hogan’s first ad attacking Brown included this sarcastic line: “He helped raised taxes 40 times in a row. He even taxed the rain.”

Environmentalists are watching carefully to assess the impact of the stormwater management efforts in various counties and cities. They are also waiting for Maryland to decide whether it is environmentally safe to drill for natural gas in western Garrett County.

The federal government recently approved a plan to build a $3.8 billion terminal at Cove Point off the Chesapeake Bay in southern Maryland that would export millions of tons of natural gas drilled in the Marcellus Shale, a long stretch of underground rock from Ohio to Virginia where a huge reservoir of the resource is trapped.

Environmental groups have filed a lawsuit to stop the project, saying it would further pollute the water and air. A final state review of impacts from hydraulic fracturing, a controversial drilling method known as fracking, is expected near the end of the year.

Brown said he would follow the recommendations of “Maryland Safe Drill,” the Marcellus Shale Safe Drilling Initiative that is studying fracking.

The lieutenant governor said the Federal Energy Regulatory Commission laid out numerous guidelines for the safe operation of Cove Point and that he would not oppose it if experts deem it environmentally safe.

Hogan has said that drilling for natural gas could be a boon to Maryland’s economy, adding revenue to state coffers and jobs to residents.

On the issue of climate change, Brown and Hogan have sharply different stances.

Hogan has indicated in the past that he is not sure that humans contribute to global warming, as an overwhelming majority of the world’s climate scientists affirm.

He also has said that he is not sure how a small state such as Maryland can stop warming, even as others argue addressing climate change requires local, national and global efforts.

An October opinion poll showed that a majority of Marylanders, nearly 60 percent, believe climate change is caused by human activity. Fifty-three percent ranked it as a major threat, 31 percent said the threat was minor and 13 said there was no threat, according to the Goucher Poll.

Most respondents rated the health of the Chesapeake Bay as poor, and 63 percent said they would support a year-long ban on the blue crab harvest out of concern for their falling population.

“It’s clear that Marylanders care deeply about their bay,” said Mileah Kromer, director of the Sarah T. Hughes Field Politics Center, which conducted the poll Sept. 28 to Oct 2.

Brown said in the interview that smoke-stack pollution and sea-level rise are particular worries for him. “I am absolutely concerned about the effects of climate change,” Brown said, especially in a coastal state where the impact is already evident.

Annapolis, the state capital, has the most nuisance flooding of any municipality on the Atlantic coast. There were close to 40 floods last year, a 925 percent increase over the four floods per year recorded on average 50 years ago,according figures compiled by the federal National Oceanic and Atmospheric Administration.

Maryland’s largest city, Baltimore, experienced a 922 percent increase in flooding over the same time, largely due to sea-level rise.

Using NOAA’s flood research to project into the future, the Union of Concerned Scientists recently issued a report saying Annapolis will experience flooding every day of the year, sometimes twice a day, by 2045.