Humboldt Bay is a natural bay and a multi-basin, bar-built coastal lagoon located on the rugged North Coast of California, entirely within Humboldt County. It is the largest protected body of water on the West Coast between San Francisco Bay and Puget Sound, the second largest enclosed bay in California, and the largest port between San Francisco and Coos Bay, Oregon. The largest city adjoining the bay is Eureka, the regional center and county seat of Humboldt County, followed by the town of Arcata. These primary cities together with adjoining unincorporated communities and several small towns comprise a Humboldt Bay Area total population of nearly 80,000 people, which accounts for nearly 60% of the population of Humboldt County. In addition to being home to more than 100 plant species, 300 invertebrate species, 100 fish species, and 200 bird species, the bay and its complex system of marshes and grasses support hundreds of thousands of migrating and local shore birds. Commercially, this second largest estuary in California houses the largest oyster production operations on the West Coast, producing more than half of all oysters farmed in California.
The Port of Humboldt Bay (also referred to as the Port of Eureka) is a deep water port with harbor facilities including large industrial docks at Fairhaven, Samoa, and Fields Landing designed to serve cargo and other vessels, while several marinas also located in Greater Eureka have the capacity to serve hundreds of small to mid-size boats and pleasure craft. Since the 1850s, the bay has been used extensively to export logs and forest products as part of the historic West coast lumber trade, with infrequent shipping occurring currently.
Aerial view of Humboldt Bay
and the City of Eureka
|Location||Humboldt County, |
North Coast, California
|River sources||Elk River; Jacoby, Freshwater, and Salmon Creeks.|
|Basin countries||United States|
|Max. length||14 miles (23 km)|
|Max. width||4.5 miles (7 km)|
|Surface area||13 square miles (34 km2)/25.5 square miles (66 km2) (min/max tide)|
|Average depth||11 feet (3.4 m)|
|Max. depth||40 feet (12 m) (dredged)|
|Islands||Indian Island, Woodley Island, Daby Island|
|Official name||Humboldt Harbor Historical District|
Humboldt Bay is the only deep water bay between the San Francisco Bay and Coos Bay, Oregon, and the Port of Humboldt Bay is the only protected deep water port for large ocean-going vessels for the large region. Despite being the only protected harbor along nearly 500 miles (800 km) of coastline, the bay's location was undiscovered or at least unreliably charted for centuries after the first arrival of European explorers to the Pacific Coast. This is partially because it is difficult to see from the ocean. The harbor opens to the sea through a narrow and historically treacherous passage, which was blocked from direct view because of sandbars, which are now managed by jetties. Contributing to its isolation were features of the coastal mountain range which extends from the ocean approximately 150 miles (240 km) inland and the common marine layer (fog) in addition to frequent clouds or rain.
The bay is approximately 14 miles (23 km) long but can be from 0.5 miles (0.80 km) wide at the entrance to the widest point at 4.3 miles (6.9 km) in the North Bay. The surface area of Humboldt Bay is 16,000 acres (65 km2) of which 6,000 acres (24 km2) are intertidal mudflats, and over 5,000 acres (20 km2) are primarily eelgrass habitat, which has been relatively constant since 1871, despite more than 80% of the bay's coastal marsh habitats having been lost or fragmented by levee, railroad and highway construction. At high tide the surface area is approximately 24 square miles (62 km2) while only 10.8 square miles (28 km2) at low tide. Each tidal cycle replaces 41% of the water in Humboldt Bay, although exchange in small channels and sloughs of the bay can take up to three weeks.
Humboldt Bay began to form when a river valley drowned about 10,000 to 15,000 years ago during a period of rapid sea level rise. Bay sediments also contain buried salt marsh deposits showing that areas of the bay have subsided during episodic large magnitude subduction earthquakes.
Three rivers, the Mad, Elk and Eel, drained into Humboldt Bay during the mid-Pleistocene. Subsequently, the Mad River cut itself a new outlet to the sea, and the flow of the Eel was diverted by tectonic uplift of Table Bluff at the southern end of the bay, but Elk River continues to drain into Humboldt Bay.
Presently, the bay is split into three regions:
Daby Island, Woodley Island, and Indian Island are in the North Bay, and all three are within the City of Eureka. Low tides reveal two more islands named Sand Island, which was formed from dredge spoils left in the early 20th century, and Bird Island. A large eelgrass bed in the South Bay which may be exposed at low tides is locally known as Clam Island.
Early explorers including Francis Drake, Sebastián Vizcaíno, Juan Francisco de la Bodega y Quadra, and George Vancouver, did not discover the bay because of a combination of circumstances: the situation of the opening to the ocean, storms, and fog. Captain Jonathan Winship is credited with the first recorded entry into Humboldt Bay by sea in June 1806 while employed by the Russian-American Company. His party, including Aleuts in baidarka to hunt sea otter, were met with hostility by the local Indians. Winship's party named it Bay of Resanof, after Nikolai Rezanov, the Chamberlain of the Tsar, and son-in-law of Grigory Shelikhov who was the founder of the first Russian colony in America.
In 1849, an expedition of seven men led by Josiah Gregg attempted to find an overland route to the Pacific Ocean. They left from the gold town of Weaverville for the 150-mile trek to the sea. Because of the density of the redwood forests, and because Gregg stopped frequently to measure latitude and the size of the trees, the expedition averaged only two miles per day. The party was near starvation when they emerged on the coast, where they discovered what is now known as Humboldt Bay on 20 December 1849. After stocking up on food, the party walked to San Francisco to report their discovery of the bay. In March 1850, two ships, the General Morgan and the Laura Virginia, were sent to the bay from San Francisco. After considerable initial difficulty with waves breaking heavily over shifting sands of the bar crossing, the ships entered the bay in 1850. The members of the Laura Virginia company named the bay after Alexander von Humboldt, a noted German naturalist.
The local Native American name for the bay was Qual-a-wa-loo, while the Wiyot nation called it "Wike" or "Wiki". Indian Island is a National Historic Landmark and one of the sites of the 1860 Wiyot Massacre.
After two years of white settlement on Humboldt Bay in 1852, only six ships sailed from the bay to San Francisco, but by 1853, on the same route, 143 ships loaded with lumber crossed the bar. Of those, despite the best efforts of local pilots and tugs, 12 ships wrecked on the bar; in times of bad weather, ships could remain in harbor for weeks before attempting the crossing. The first marker at the harbor entrance was placed in 1853. The U.S. Federal Government authorized funds for a lighthouse near the mouth. In 1856 the Humboldt Harbor Light was built on the north spit. In 1872 a bell boat was added, and two years later, a steam whistle replaced the bell to assist mariners during times of dense fog. Eighty-one people drowned between 1853 and 1880 during bar crossings, including the captain of the brig Crimea who was washed overboard on the bar crossing on 18 February 1870. The Humboldt Bay Life-Saving Station is on the bay side of the North Spit south of the World War II era blimp base.
By the 1880s, long wharves were built into the bay for the lumber shipments, and shipbuilding became a key part of the process. The Bendrixson shipyards produced 120 ships on Humboldt Bay. > Shipping reached about 600 vessels a year by 1881. Humboldt Bay was made an official port of entry in 1882, which permitted shipping directly to overseas ports. In 1886, fierce storms nearly destroyed the Harbor Light, and it was replaced by the Table Bluff Light.
The unimproved state of the mouth of the bay was a crescent-shaped bar covered by a line of breaking waves. The entrance of the bay is protected by two sand spits, named South Spit and North Spit. The bay mouth was stabilized by jetties, with one jetty projecting from each spit. The South Spit jetty was built starting in 1889, but by 1890 it was apparent that it was eroding the North Spit and widening the channel. The jetties are approximately 6,000 feet (1,800 m) long and 2,200 feet (670 m) apart. Storm damage led to rebuilding of the jetties in 1911, 1927, 1932, 1939, 1950, 1957, 1963, 1971, 1988 and 1995. Entrance currents are strong, ranging from 2.0 knots average maximum ebb and 1.6 knots average maximum flood; although peak rates can be nearly twice as high.
In 1971 and 1984, 42 short tons (38 t) dolosse were added in two layers to secure the jetties, which are maintained by the U.S. Army Corps of Engineers. In 1972, 4,796 dolosse were manufactured locally; 4,795 of them are on the jetties, while the last one is located outside the Eureka Chamber of Commerce. In 1983, 1,000 more dolosse were made at the South Spit yard and left to cure; local newspapers named the curing site "Humboldt's Stonehenge." In 1985, 450 of the dolosse were shipped 35 miles (56 km) around the bay to be placed on the North Spit. At that point, more than $20,000,000 had been spent in total to protect the entrance to Humboldt Bay. The jetties were named an American Society of Civil Engineers California historical civil engineering landmark in 1977, and a national historical civil engineering landmark in 1981. The jetties are inspected annual by the U.S. Army Corps of Engineers. In 1996, the inspection showed that 34 of the dolosse had cracked, 17 on each jetty, mostly near the southern seaward head.
Dredging of channels for shipping began in 1881; periodic dredging of the entrance and shipping channels keeps them from 38 feet (12 m) to 48 feet (15 m) deep. These changes have led to severe erosion at the entrance, where approximately 188 acres (0.76 km2) of Buhne Point, which had formerly visually blocked the entrance to the bay, washed away between 1854 and 1955.
Most of the large sloughs around the bay have protected with levees. Of the 10,000 acres (40 km2) of historic intertidal marsh, only about 10% remains because of land reclamation for hay or pasture, as well as the construction of the Northwestern Pacific Railroad in 1901, which reduced tidal connectivity along the eastern edge of the bay.
Humboldt Bay and its tidal sloughs are open to fishing year-round, and the bay is home to the Humboldt Bay National Wildlife Refuge, created in 1971 for the protection and management of wetlands and bay habitats for migratory birds. The Humboldt Botanical Garden at the College of the Redwoods near the Bay preserves and displays local native plants. Humboldt Bay is recognized for protection by the California Bays and Estuaries Policy.
In the winter, the bay serves as a feeding and resting site for more than 100,000 birds. Birds found on the bay include gull species, Caspian tern, brown pelican, cormorant, surf scoter, and common murre.
The bay is a source of subsistence and sport fishing for a variety of salt-water fish, crustaceans, and mollusks. Dungeness crab are fished commercially, and oysters are commercially farmed in the bay. The bay supports over 100 species of marine and estuarine fish, including green sturgeon, coho and Chinook salmon, steelhead and coastal cutthroat trout which spawn and rear in its watershed, covering an area of 223 square miles (580 km2). Coho salmon primarily rear and spawn in Elk River, Freshwater Creek, and Jacoby Creek, where a recent study found that 40% of coho in the system rear in the estuary. The federally endangered tidewater goby is found in the bay, along with more common three-spined stickleback, shiner perch and Pacific staghorn sculpin.
The bay has been invaded by the European green crab, a voracious predator that is known to prey on the young of native crab species, as well as native mussels, oysters, and clams. European green crab were first documented in Humboldt Bay in 1995 and have been blamed for a decline in clam harvesting.
Marine mammals are represented by harbor porpoises, harbor seal, California sea lion and river otter, with Steller sea lion and gray whale found immediately offshore. Leopard sharks have been reported inside the bay which also provides habitat for young bat rays, feeding on clams, crabs, shrimps, worms, sea cucumbers, brittle stars, various gastropods and isopods.
About 80,000 people reside on the shore of the bay in at least 20 named settlements on the coastal plain around the bay estuary; most of these are unincorporated suburbs of the City of Eureka.
Settlements located on or near the bay, listed clockwise from the north side of the bay entrance:
Streams and sloughs that enter into Humboldt Bay are listed north to south, clockwise, with tributaries entering nearest the bay listed first. The primary streams of major watershed areas east of the bay (draining a combined area of 288 square miles (746 km2)) are in bold.
Humboldt Bay Harbor Recreation and Conservation District is the governing body of Humboldt Bay, the Port of Humboldt Bay, and the Port of Eureka. Maritime pilots trained and employed by the district are the only persons authorized to bring vessels beyond a certain size into the bay unless the ship's pilot has proper certification because despite the jetties and dredging, the harbor entrance remains challenging. The district maintains a 237 berth marina at Woodley Island, serving both recreational and commercial boats and a shipping dock located in South Bay.
Dangerous sand bars and shifting currents have caused many shipwrecks at the entrance to Humboldt Bay. Forty-two ships were wrecked in and around the channel, most of them under tow by a tug boat. Fifty-four ships were wrecked on the Humboldt County coastline. Most shipwrecks occurred between 1850 and 1899.