Sewage overflows keep shutting down Humboldt Bay oyster harvests, hurting farmers

Sewage overflows have become an economic hazard for Humboldt Bay’s oyster growers, shutting down harvests with little warning and putting a signature local seafood industry on hold. When contamination triggers an emergency aquaculture closure, farms must stop harvesting immediately, even if crews are ready, buyers are lined up and product is already moving toward market.

For Todd Van Herpe’s Humboldt Bay Oyster Company, that kind of closure can freeze the business in place. The company’s shellfish operation was established in 1978, later purchased from Kuiper Mariculture in 2002, and now raises Pacific oysters, Kumamoto oysters and Manila clams in the north bay on roughly three acres. A 2026 project filing lists Van Herpe as the sponsor of the Humboldt Bay Oyster Company Shellfish Farm project. In practical terms, each shutdown can delay shipments, force recalls and erase planned work for days or weeks at a time.

The problem is not theoretical. A Jan. 13, 2024, sewage spill released 1,275 gallons from Arcata’s wastewater system into Humboldt Bay and led to a shellfish closure that lasted until Feb. 3, 2024, a 19-day shutdown during a critical stretch for growers. That spill became the 26th sewage spill in Humboldt County that year and the fifth hazardous-materials incident recorded in the Arcata area at that point in 2024. Pacific Seafood later sued the City of Arcata over losses tied to the spill and settled for $71,500 in March 2026.

State public-health rules are what make the closures mandatory. California’s Department of Public Health coordinates shellfish safety monitoring, and the Preharvest Shellfish Unit orders emergency closures when contamination threatens safe harvest. For oyster farmers, those closures can stack up with rainy-season shutdowns and leave them without harvest income for months in a year, even while seed planted years earlier is still tied up in the bay.

The financial pressure comes as Arcata continues to grapple with wastewater infrastructure costs. The city approved a water and wastewater rate increase on April 16, 2026, while its wastewater-treatment improvement project has been underway since July 2020. State water-board materials from 2025 and 2026 also show ongoing regulatory work on exceptions to the policy that prohibits waste discharges to Humboldt Bay.

Humboldt Bay’s oyster industry has deep roots, with Pacific oyster seed introduced in the 1950s, and its harvests remain closely tied to the region’s identity. Repeated sewage spills now threaten more than water quality. They interrupt paychecks, unsettle buyers and expose a small but important local industry to losses it cannot control.