Wailua River
Rainfall is the source of all fresh water in Kauai where a part of the rainfall runs off directly to the sea in streams. There is a part of the stream that escapes into the atmosphere by evaporation and transpiration, and part moves downward through the soil and rocks to the zone of saturation and becomes ground water. The ground water moves slowly through the rocks and eventually reaches points of discharge at springs and seeps in stream valleys and along the shore.
The main aquifers, or water-bearing rocks of Kauai are the lava flows that make up the make of the island. The lava openings hold the ground water where the water moves. In unweather rocks, water moves freely through the openings in between lava flows. These openings are the most important to the ground water supply. Usually, lava tubes can send massive quantities of water although these tubes are not common in the rocks of Kauai.
The rivers of Kauai include Hanalei River, Ko’ula River, Hanapepe River, Lumahaʻi River, Wailua River, Waimea River. Kauai has the only navigable rivers in the state and the longest river is Wailua River 19.3 miles. The Wailua River on Kauai is the only navigable river by boats larger than kayaks. Smaller navigable waterways include the Waimea, Hanape’pe, Lumahaʻi, and Hanalei Rivers.
Wailua River, fed by two waterfalls, Opaeka’a and Wailua that are each within the boundaries of the Wailua River State Park is known as the only navigable river in the state. In other words, it can accommodate larger vessels. What this means for visitors who enjoy exploring regions of this nature is that there is an overabundance of water-related activities take place here.
Hanalei River
The Hanalei River on the island of Kauaʻi in Hawaii flows north from the eastern slopes of Mount Waiʻaleʻale for 26.5 km (16.5 mi) until it reaches the Pacific Ocean at Hanalei Bay, river mouth. With a long-term mean discharge of 216 cubic feet (6.12 cubic meters) per second, in terms of water flow it is the second-largest river in the state; although its watershed of 57 square kilometers (22 sq mi) is only sixth largest on Kauaʻi, it encompasses areas of the highest recorded rainfall on the planet and plunges precipitously from its headwaters at 3,500 feet (1,100 m) above sea level.
The lower, flatter part of the river flows by Hanalei National Wildlife Refuge and many taro farms (60% of Hawaii’s taro is grown in this area). The Hanalei River supplies habitat for a number of amphidromous species, including gobies (5 native varieties), two native species of crustacean, the hīhīwai (Neritina granosa, an edible snail), and in its upper reaches, a threatened species of highly adapted snail (Newcomb’s snail, Erinna newcombi).
The Hanalei River was designated an American Heritage River by US President Bill Clinton on July 30, 1998. The major bridge across the river (still one lane) is on Hawaii Route 560, which is listed on the National Register of Historic Places listings in Hawaii.
Waimea River
The Waimea River is the largest and the longest river on the island of Kauai in the U.S. state of Hawaii. At 35.7 km (22.2 mi) in length, it is the third longest rivers in the Hawaiian Islands, draining one sixth of the total area of the island. It rises in a wet plateau of the island’s central highlands, in the Alaka’i Swamp, the largest high-elevation swamp in the world. It flows south, passing through the spectacular 3,000-foot-deep (910 m) Waimea Canyon, known as the “Grand Canyon of the Pacific.” The valleys of the Waimea River and its branch, the Makaweli River, were once heavily populated. It enters the Pacific Ocean at Waimea, near the 1778 landing place of Captain Cook on Kauai.
The mystical Menehune ditch parallels this river as it traverses water alongside and through the mountains of Waimea. Today, the river is an active home for the local canoe club where you can find canoes filled with children at paddle practice. The taro farmers use the waters in their cultivated fields that neighbor the river perpetuating the land use practices.
Hanapepe River
The Ko’ula River or Koula is the largest tributary of the Hanapēpē River on the island of Kauai. It rises at 4,642 ft (1415 meters) on the slopes of Mt. Wai’ale’ale and flows south for 9.2 miles to its confluence with the Manuahi Stream. Beyond this point it is known as the Hanapepe River. The river has a long-term mean discharge of 85.2 cubic feet (0.99 cubic meters) per second.
The Hanapepe River is a river on the Hawaiian island of Kauai. It begins at the confluence of the Ko’ula River with the Manuahi Stream and flows south, with a total length of 24.2 km (15.0 mi) to its mouth at Hanapepe and Eleele in the Pacific Ocean. The watershed covers an area of 27.7 square miles, draining roughly a twentieth of the island. The name Hanapepe translates to “crushed bay,” which may refer to landslides in the area. The river drains the fertile Hanapepe Valley, a region that was historically used for growing rice, taro, coffee, and sugarcane. During the late 19th and early 20th centuries, the valley attracted Chinese, Japanese, Korean, and Filipino immigrant workers, many of whom started their own farms or businesses. More recently, the Hanapepe Valley was used for filming parts of the 1993 Steven Spielberg film Jurassic Park. Near its mouth in Hanapepe, the river passes under the Hanapepe Swinging Bridge. The footbridge was built in 1911 to provide Hanapepe residents with a way to cross the river and was restored in 1992 after Hurricane Iniki. Considered a local tourist attraction, the bridge is popular with children due to its tendency to rock back and forth.
Lumaha’i River
The Lumaha’i River is a river of northern Kauai, Hawaii, US. It begins in a narrow, high-walled valley in the central mountains and enters the Pacific Ocean on the northwestern coast of the island, just east of Wainiha, on the western edge of Lumaha’i Beach. Unaffected by development, its pristine waters hold populations of o’opu (Stenogobius hawaiiensis) and hīhīwai (shellfish) as well as the Hawaiian coot.
During heavy rainfall in winter and spring, it is prone to flooding. The Lumaha’i River Bridge traverses the waterway. The Lumaha’i River rises in the central mountains of Kauai at an elevation of 430 meters (1,410 ft). It drains a catchment area of twenty-three square miles (60 km2). After flowing through a narrow valley with cliff banks, it opens out midway along its course into a wide valley, where the banks of the river are steep. The river debouches into the Pacific Ocean on the northwestern coast of the island, just east of Wainiha, on the western edge of Lumaha’i Beach. The beach at the western end, formed at the mouth of the river, is called the Lumaha’i Beach which is found 1.4 miles (2.3 km) to the northwest of Hanalei. Measuring 4,000 feet (1,200 m) in length, the beach has rocky features at the mouth of the Lumaha’i River, which results in treacherous “rip currents”. The beach is remembered as the scenic location for a song sequence in the 1958 film South Pacific. The Lumaha’i river valley once witnessed taro and rice farming by the immigrant farmers from other regions of Hawaii, China, and Japan, between 1890 and 1930. But it is presently uninhabited.