Geography of Hawaii County, Hawaii

Geography of Hawaii County, Hawaii

Hawaii County, also known as the Big Island, is the largest and most geographically diverse island in the state of Hawaii. Its landscape encompasses volcanic mountains, lush rainforests, coastal plains, and stunning beaches. From the snow-capped peaks of Mauna Kea to the fiery lava flows of Kilauea, the island’s geography is both breathtaking and dynamic.

Topography and Landscapes:

According to Lightinghowto, Hawaii County’s topography is shaped by volcanic activity, with five major shield volcanoes dominating the island’s landscape. These volcanoes include Mauna Kea, Mauna Loa, Hualalai, Kohala, and Kilauea, each contributing to the island’s diverse terrain.

Mauna Kea, the tallest peak in Hawaii, rises to an elevation of 13,796 feet above sea level. Despite its impressive height, Mauna Kea is best known for its astronomical observatories, which are situated atop the mountain’s summit and provide unparalleled views of the night sky.

Mauna Loa, the largest volcano on Earth in terms of volume, is located just south of Mauna Kea. Its massive shield shape dominates the southern half of the island, with its summit reaching an elevation of 13,678 feet. Mauna Loa is one of the most active volcanoes in the world and has erupted numerous times in recorded history.

Kilauea, located on the southeastern side of the island, is one of the most active volcanoes on Earth. It has been continuously erupting since 1983, producing lava flows that have reshaped the island’s landscape and added new land to its southeastern coastline. Kilauea’s summit caldera, Halemaumau, is a popular tourist destination known for its glowing lava lake.

In addition to its volcanic features, Hawaii County is home to lush rainforests, coastal plains, and sandy beaches. The island’s eastern side, in particular, receives abundant rainfall, supporting dense vegetation and vibrant ecosystems. The western side of the island is drier, with grasslands and scrub vegetation dominating the landscape.


Hawaii County’s climate varies depending on elevation and location, with distinct microclimates present throughout the island. Generally, the island has a tropical climate, characterized by warm temperatures, abundant sunshine, and consistent trade winds.

Coastal areas of Hawaii County experience warm temperatures year-round, with average highs ranging from the upper 70s to the low 80s Fahrenheit. Nights are usually cooler, with lows in the 60s Fahrenheit. Trade winds from the northeast help moderate temperatures and provide relief from the heat.

As elevation increases, temperatures tend to drop, with cooler conditions prevailing at higher elevations. Mauna Kea and Mauna Loa, for example, experience alpine conditions at their summits, with snowfall occurring during the winter months.

Rainfall patterns in Hawaii County are influenced by trade winds, elevation, and proximity to mountains. The island’s eastern side, facing the prevailing winds, receives more rainfall than the western side, resulting in lush rainforests and verdant valleys. The town of Hilo, located on the eastern coast, is one of the wettest places in the United States, receiving over 120 inches of rainfall annually.

In contrast, the western side of the island, known as the Kona Coast, is much drier, with rainfall totals averaging less than 20 inches per year. This area is sheltered from the trade winds by the volcanic mountains, creating a rain shadow effect and producing arid conditions.

Rivers and Lakes:

Despite its volcanic origins, Hawaii County has relatively few rivers and lakes compared to other regions. The island’s rugged topography and porous volcanic rock limit the formation of permanent water bodies, with most freshwater sources found in the form of streams and springs.

The Wailuku River is one of the largest rivers in Hawaii County, flowing from the slopes of Mauna Kea to Hilo Bay on the eastern coast. The river passes through scenic gorges and waterfalls, including the iconic Rainbow Falls, before reaching the ocean.

Other notable rivers on the island include the Wailoa River, the Hamakua Ditch, and the Kohala Ditch. These waterways provide habitat for freshwater fish, shrimp, and other aquatic species, as well as opportunities for recreation such as kayaking and fishing.

Hawaii County also contains several natural springs and ponds, such as the Kapoho Tide Pools and Ahalanui Hot Springs, which are popular destinations for swimming and snorkeling. These geothermal features are fed by underground aquifers and heated by volcanic activity, creating warm and inviting waters for visitors to enjoy.

Natural Resources:

Hawaii County’s geography is rich in natural resources, including fertile soils, geothermal energy, and marine biodiversity. The island’s volcanic soils support a variety of crops, including sugarcane, coffee, macadamia nuts, and tropical fruits. Agriculture has played a significant role in the island’s economy and culture for centuries, with many farms and plantations still in operation today.

Geothermal energy is another important natural resource in Hawaii County, with several geothermal power plants harnessing the island’s volcanic heat to generate electricity. These plants produce clean, renewable energy that helps reduce the island’s dependence on imported fossil fuels and mitigate greenhouse gas emissions.

The waters surrounding Hawaii County are home to a diverse array of marine life, including coral reefs, fish, sea turtles, and marine mammals. Coral reefs provide habitat for thousands of species and support important industries such as fishing, tourism, and recreation. The county’s marine resources are protected and managed through conservation efforts and marine reserves.


In summary, Hawaii County, also known as the Big Island, offers a diverse and dynamic geography shaped by its volcanic origins, lush rainforests, coastal plains, and stunning beaches. From the snow-capped peaks of Mauna Kea to the fiery lava flows of Kilauea, the island’s landscapes provide a unique and breathtaking backdrop for exploration and adventure.

The island’s tropical climate, abundant rainfall, and fertile soils support a rich array of ecosystems and habitats, while its rivers, streams, and springs provide freshwater resources for residents and wildlife. As Hawaii County continues to grow and evolve, its geography remains a fundamental aspect of its identity, shaping the lives and experiences of its residents and visitors for generations to come.