The line's limited capacity was more than adequate for a community where the average household use was a modest 500 to 1,000 kilowatt hours of electricity per month.
Then growers moved their crops indoors and installed high-intensity lights.
"We maxed out our system very quickly when this started," said Richard Culp, the resort's general manager. "We're seeing 5,000, 6,000, 8,000, 9,000 kilowatt-hours of use a month."
Hoping to halt the trend, the resort's utility nearly tripled the hourly rate for usage above 2,000 kilowatt-hours a month. When that made no difference, the rate for heavy usage was raised to five times the normal charge. Growers simply added more plants and lights to generate income to pay the extra cost.
The cove's backup generator had to be replaced, at a cost of $500,000. Last year, PG&E informed Shelter Cove that it would have to kick in $300,000 to expand the capacity of the electrical line.
In all, the resort estimates that indoor pot-growing has cost its residents more than $1 million since 2005.
Residents say indoor growing also brought a lawless feel to the cove: nighttime gunfire; planes landing and taking off in darkness from the resort's airstrip; late-night parties; trashed rental housing; truck races along Upper and Lower Pacific Drives.
"It was the wild, wild West," said Roger Boedecker, a member of the Shelter Cove Resort Improvement District board of directors. "The D.A.'s office is reputed not to be inclined to prosecute small growers. You can grow with impunity."
The indoor marijuana boom split Shelter Cove between younger growers, most of them renters, and older retirees, some of whom desperately hope for pot's legalization, believing it will drain the profits from illegal cultivation.
This was the situation Hamilton found when he arrived. He began by ticketing people for dilapidated trailers, for growing pot on land where they didn't live, which is against state law, or for living on land without a septic system. But Hamilton said the county's building department objected, saying he was doing its job, one he wasn't trained for.
He asked for guidance from the sheriff's department on what to do about full-grown plants capable of producing more pot than a medical marijuana user could possibly need. "Some of them are 8 feet tall, for God's sake," he wrote in an e-mail.
He was given a formula for calculating whether a grower was exceeding the county-permitted plant canopy of 100 square feet per medical patient.
"The current climate is to [go after] big commercial growers, ignore small grows," said Humboldt County Sheriff Gary Philp. "But you see more and more grow houses. If they're not going to be prosecuted, at a certain point they affect the community. We've had home invasions, shootings, homicides."
Gallegos, who is seeking a third term as district attorney, bridles at the idea that his office has been soft on illegal marijuana farming. He said he cracks down on illegal grow houses when he has the evidence, but also tries to protect patients' access to pot for legitimate medical needs.
"If someone has a [medical marijuana] recommendation, and they're within the ordinances, it's presumed they're lawful," Gallegos said. He faulted the county supervisors for enacting weak regulations on medical marijuana that, he said, invite abuse by commercial growers.
Far from these debates, Hamilton navigates the roads, armed with skepticism and a smile. Deputies in other counties may have broad citizen support. In marijuana country, he finds, it depends.
In May, Hamilton saved the life of a distraught woman who had slit her own throat with a butcher knife. Comments posted on blogs popular among growers were effusive in their praise of the deputy.
But the grower community also serves as an early-warning system. The sight of a sheriff's car activates a phone tree that Hamilton has found can extend to growers who live outside the county but own property there.
Once, when Hamilton was chasing a grower, word apparently spread and numerous slow-moving trucks appeared on the highway, hindering his progress. The suspect got away, he said.
"There's no community that we can sneak up on," Hamilton said.
Some Shelter Cove growers have objected to his mere presence.
A service organization known as the Shelter Cove Pioneers met in April to consider whether to renew its $200 monthly subsidy of Hamilton's rent, which makes it possible for him to live in the community. A few days earlier, several growers had joined the Pioneers, Hamilton said, and they had the votes to end the rent subsidy.
Their attitude seemed to be: "I'm growing marijuana, and I don't want this guy around," said Jim Blewett, Pioneer board president.
A group of residents later pooled their money to continue subsidizing Hamilton's rent. (At a Pioneers meeting this month, with many of the new members absent, the organization voted to resume the subsidy.)
