EAST FAIRFIELD TOWNSHIP — “Fire in the hole!,” yelled a bomb squad officer.

A few seconds later came one loud — very loud — boom from the southernmost shore of Tamarack Lake.

Explosives experts from Erie-area police departments, Pennsylvania State Police and deputies of the Crawford County Sheriff’s Department were among those called to that East Fairfield Township location Friday morning after workers with the Pennsylvania Fish and Boat Commission discovered a live grenade in the drawn-down, shallow waters of Tamarack Lake. The PFBC recently drew the lake’s water level down another 5 feet as it works to define and address deficiencies in the lake’s northern dam, and the grenade was discovered Friday as staff were at the southern dam area working to relocate some living fish to other nearby bodies of water while removing what are expected to amount to thousands of dead and dying fish. Those fish are being buried in wooded state property near the lake.

With the lake’s facilities having recently been closed in response to the drawdown and related ongoing work, the public and media weren’t allowed any type of close access to the brief grenade detonation activity Friday. Explosives experts and other law enforcement personnel at the scene weren’t available for comment, but regional PFBC spokesperson Keith Edwards confirmed a previously undetonated hand grenade was discovered in the waters during the morning.

“They saw it lying there” in the water — which currently reportedly stands at between 3 and 5 feet in the basin’s pooled areas — and “obviously, called the police immediately to get rid of it,” said Edwards, adding “that was a bit of a surprise” for the PFBC staff as they worked to remove fish from the drawn-down lake.

“We’ve been trying to get as many live fish as we can” out of the water and relocated to other waterways close by, said Edwards, while others that are dead or determined to be under too much stress to survive transport are being taken out of the water and, using heavy equipment, trucked into a wooded area and being buried.

The numbers of live and dead fish being removed from the lake “have not even been tallied” at this point as the work continues, said Edwards, but PFBC officials recently said it’s expected that thousands of fish will die there in coming weeks because of low water levels, low oxygen levels and high temperatures in the remaining water.

Normally between 13 and 15 feet deep, Tamarack first was drawn down approximately 5 feet in November 2011 after Fish and Boat Commission officials observed water seeping through the dam and from underneath its outlet at that time. When completed, the most recent drawdown is leaving parts of the lake’s 562-acre basin muddy or dried up.

Removing and burying the fish on state land nearby was taken as the chosen measure in response to that effort because “it’s mostly a public health and safety issue,” said Edwards. “If we leave them to float,” he said, “it would be a stinking mess.”

The commission’s deputy director recently forecasted a four- to five-year timeline to complete necessary upgrades to both the lake’s southern and northern dams — a project that could be in the millions or tens of millions of dollars.

Addressing the problem is “all a matter of money,” said Edwards. And “it’s not an easy task.”

The commission has indicated it will seek money from the state Commonwealth Financing Authority through the H20 PA Act, which provides grants for flood control projects, to rebuild and upgrade the lake’s two dams. The letter also indicated that the state Department of Environmental Protection has classified Tamarack as a flood control facility and that both of its dams must be upgraded to meet current standards.

With stated support from a variety of local and county officials, Friends of Tamarack Lake — a group of lakeshore residents and others who use the lake for recreation — has also been very active lobbying local and state officials to repair the dam and refill the lake, which has several public access points and is a popular fishing and boating site.

Tamarack Lake was built in the early 1960s. The lake also is used for fire protection and recreation while the lake and its environs are used for wildlife habitat.

Located southeast of Meadville, its reservoir covers 562 acres in West Mead, East Mead and East Fairfield townships.