The Spanish Bight: Coronado's Lost Waterway

When early European navigators rounded Point Loma, beginning with Juan Rodríguez Cabrillo in 1542 and Sebastian Vizcaíno in 1602, their hand-drawn charts consistently portrayed the Coronado landmass as severed into two pieces. The southern island, anchored by the long peninsula of the Silver Strand, terminated at a wide saltwater inlet. Across that inlet lay an uninhabited, brush-covered barrier island of sand dunes, sagebrush, and nesting sea fowl, referred to colloquially by Spanish soldiers as Isla del Norte (North Island).

The waterway linking the Pacific Ocean to San Diego Bay was named the Spanish Bight. Driven by powerful tidal ebbs and winter storm swells, the channel was dynamic and mercurial. At spring low tides, the strait would narrow into a network of winding tidal pools, eelgrass mudflats, and sandbars shallow enough for adventurous horse riders or livestock to wade across. But when full moon swells swept through from the open sea, the Bight deepened into a surging, frothing ocean channel several fathoms deep, spanning over 1,200 yards wide.

For the Kumeyaay people who camped seasonally along the Coronado peninsula for millennia, the Spanish Bight was an extraordinarily productive marine pantry. The calm, brackish shallows formed a nursery for Pismo clams, scallops, bay rays, and juvenile halibut. Archaeological digs in the 1930s uncovered massive shell middens along the former southern shore of the Bight, confirming centuries of seasonal maritime harvesting before European colonization.

The natural isolation afforded by the Spanish Bight played an accidental, foundational role in the history of global warfare: the birth of American naval aviation. In December 1910, inventor and aviation pioneer Glenn H. Curtiss struck an agreement with John D. Spreckels to establish a winter aviation camp free of charge on North Island.

Curtiss selected North Island over hundreds of competing coastal sites for two decisive physical reasons directly dictated by the Spanish Bight:

• 1. Absolute Seclusion from Patent Competitors: Curtiss was locked in fierce, bitter patent litigation with the Wright Brothers. Because North Island could only be reached by boat across the Bight or San Diego Bay, Curtiss could station guards at the boat landings and test experimental wing warps and pontoons in total secrecy.
• 2. Mirror-Calm Takeoff Basins: The rudimentary floats of early hydroaeroplanes could not survive ocean surf. The protected embayment of the Spanish Bight provided mirror-smooth salt water unaffected by open-sea breakers, allowing Curtiss to execute the world's first successful seaplane takeoff and landing on January 26, 1911.

Within weeks, Curtiss trained the first naval aviator, Lt. Theodore G. Ellyson, USN, and on February 17, 1911, Curtiss flew his hydroaeroplane from the calm waters of the Spanish Bight out to the armored cruiser USS Pennsylvania anchored in San Diego Bay, where the plane was hoisted aboard by crane and launched back into the water, proving the concept of carrier aviation.

Following the attack on Pearl Harbor on December 7, 1941, Naval Air Station North Island emerged as the supreme logistics, repair, and staging hub for the entire United States Pacific Fleet. Every aircraft carrier deploying into combat in the Pacific, from the USS Enterprise (CV-6) to the USS Lexington (CV-2) and USS Yorktown (CV-5), called at North Island to take on aircraft squadrons, munitions, spare engines, and aircrews.

By 1943, however, naval aviation had radically transformed. Lightweight biplanes were replaced by massive, multi-engine heavy patrol bombers and long-range transport aircraft, including the four-engine Consolidated PB2Y Coronado flying boat and the land-based Consolidated PB4Y-2 Privateer. These aircraft required uninterrupted 8,000-foot paved runway complexes aligned with prevailing ocean winds.

North Island's constrained borders, choked off by the tidal waters of the Spanish Bight, could not accommodate the necessary runway extensions. The U.S. Navy Bureau of Yards and Docks faced an unprecedented engineering decision: bridge the channel, or erase it entirely.

In early 1944, a massive fleet of 24-hour hydraulic cutterhead dredges went to work in San Diego Harbor. Steel pontoon discharge pipelines were laid across the bay. Night and day, the dredges sucked millions of tons of bay-floor sediment, sand, and shells, pumping high-pressure slurries directly into the mouth of the Spanish Bight. Over the course of 18 months, an astonishing 28 million cubic yards of marine fill were deposited into the strait.

By mid-1945, the Spanish Bight was no more. The water ceased to flow; the tidal currents were extinguished; and North Island and South Island were welded into a single unbroken physical peninsula. Across the newly settled land, Navy construction battalions poured thousands of tons of reinforced concrete, completing the runway intersections that sustained the final naval offensives against the Japanese home islands.