WEST GREENWICH, R.I. — Some 15 years ago, when Rhode Island mapmaker Cliff Vanover was regularly traversing the Big River Management Area, he noticed the buildup of silt in some of the property’s unnamed streams and brooks and occasionally found the water running cloudy.

The Charlestown resident made a mental note of his observations as he worked to create a hiking map of the 8,319-acre South County woodland. When the avid hiker and cartographer finally returned to Big River last year, he immediately noticed the property’s silty waters. He returned last month, after a heavy rain, to document his concern about the damage being caused by runoff.

He e-mailed ecoRI News a few of the pictures he had taken on last month’s hike. The color of the murky waters in the photos reminded this reporter of Campbell’s mushroom soup from his childhood.

“I saw it happening 15 years ago,” Vanover said. “I don’t know what happened in between, but the problem has gotten worse. There’s a lot of silt.”

ecoRI News accompanied Vanover on an April 17 hike of the area — a day after heavy rains had soaked the region. We met in a Hopkins Hill Road parking lot and entered Big River on the other side of the road.

The Big River Management Area is steep in places and dotted by hiking trails. Mountain-bike paths have expanded the area’s network of trails, which are responsible for their share of runoff problems.

However, the biggest culprit seems to be quarry runoff that flows off property owned by one of the more recognizable corporations in the state and onto land owned by the Rhode Island Water Resources Board and managed the Rhode Island Department of Environmental Management (DEM).

Hopkins Hill Sand & Stone LLC — an arm of the Cardi Corp. — sells washed concrete sand, washed asphalt sand, bank gravel and pond fill, among other products. The mining operation, which borders the Big River Management Area, also conducts blasting, as this 2016 Cardi Corp. video on YouTube and this 2017 Facebook video show.

During our 2-hour Big River hike on April 17 we saw plenty of evidence of runoff damage, such as accumulating silt on rocks and stream beds and out-of-place gravel and rocks that could only be classified as washed-away quarry debris.

Along one side of a paved roadway to the mining operation — the side nearest the DEM-managed property — was a small desert of quarry sand. A noticeable path of this blasted and crushed debris stretched into the woods.

ecoRI News contacted both the Rhode Island Water Resources Board, through the Department of Administration (DOA), and DEM. A DOA spokeswoman wrote in an e-mail that she was copying a colleague from DEM “who may be the more appropriate contact for your questions.”

A DEM spokeswoman wrote in an e-mail that, “The Department has not received any complaints related to runoff into Big River Management Area from the Hopkins Hill Sand & Stone. We will log in your inquiry as a complaint and conduct an inspection of the site.”

Neither ecoRI News nor this reporter requested that a complaint be filed, and the reporter informed the DEM spokeswoman that wasn’t the nature of ecoRI News’ media request. It was a request to speak with someone from the state agency about Big River’s runoff problems. No one was made available for an interview.

ecoRI News did speak with Steve Cardi II, a managing member of Hopkins Hill Sand & Stone, about quarry runoff concerns. He blamed the “unbelievable” rains of the past month for any current issues. He said the operation every spring checks on its erosion controls, such as silt fencing and hay bales.

Cardi said the quarry has never had a runoff issue come up. When asked how long the quarry has been in operation, the 58-year-old said, a long time, “since I was a little kid.”

Waterbodies in the Big River Management Area include the Big, Carr, Congdon and Nooseneck rivers; Carr, Tarbox, Sweet, Reynolds and Capwell Mill ponds; and Bear Swamp.

In 1964, the Rhode Island Water Resources Coordinating Board — since renamed the Rhode Island Water Resources Board — was formed, largely to acquire and protect 8,600 acres in West Greenwich and Coventry for the proposed Big River Reservoir Water Supply Project. The reservoir idea was actually initiated in 1928.

Under the powers of eminent domain, the state began acquiring property by condemnation, beginning in Coventry in 1965, West Greenwich in 1966 and the in the Wood River area in Exeter in 1967, according to a 1997 report by the Rhode Island Water Resources Board.

Because of substantial litigation, both the amount of land and the cost of acquisition exceeded “desired proportions.” In the end, the state obtained a total of 8,600 acres from 351 owners, comprising 444 parcels, at a cost of $7.5 million.

By the late ’80s, then-Gov. Edward DiPrete wanted to build a $90 million reservoir in the management area, telling The New York Times that the project was essential to Rhode Island’s water needs.

“‘We’re headed for a crisis, and I can’t let that happen,” DiPrete is quoted as saying in the 1988 article.

The proposed project involved the construction of a dam 2,300 feet long and 70 feet high to create a 3,400-acre impoundment with an average depth of 25 feet.

The Environmental Protection Agency (EPA) had a different take, saying the state hadn’t fully explored other water-conservation methods. The federal agency noted that the project would result in the largest single taking of wetlands in New England since the passage of the Clean Water Act in 1972 and would flood 3,700 forested acres.

The EPA said it would veto the project because it would flood marshes and swamps that are home to a variety of wildlife, according to The New York Times story.

Five years later, the General Assembly declared that the Big River Management Area would be considered open space until needed as a drinking-water supply. The reservoir idea was considered again nearly two decades later.

In late 2009, the Rhode Island Water Resources Board successfully drew water from test wells in the Big River Management Area. State officials would seize on that news, believing the wells to be economic tools that could help jump-start the Ocean State’s struggling economy, according to a Providence Business News story.

Despite the EPA’s objection to developing a reservoir on the property, because of environmental impacts, many Rhode Islanders, including former or then-current Rhode Island Water Resources Board officials, believed the plan could be revised and turned into a federal project supported by federal stimulus money.

William Falcone, the former chief of staff for the Water Resources Board, told the Providence Business News in 2010 that the project would put people to work in a state suffering from high unemployment.

“If you want economic development, build a reservoir,” Falcone is quoted.

Midway through our April 17 hike, Vanover, unprompted, simply said, “It’s really beautiful here.”