Question 1

Where can I swim in Hawaii during a brown water advisory?

Accepted Answer

Brown water advisories affect beaches near stream mouths, storm drains, and urban runoff zones. Reef-protected beaches and man-made lagoons on each island are far less affected because they sit away from these sources. On O'ahu, Ala Moana Beach Park (with Magic Island Lagoon) and Ko Olina Lagoons are typically less affected alternatives. On Maui, Kapalua Bay and Wailea Beach. On Kauai, Po'ipu Beach (Baby Beach section) and Anini Beach. On the Big Island, Hapuna Beach and Mauna Kea Beach. Always check the live advisory status for any beach before entering the water.

Question 2

Which Hawaii beaches are least affected by brown water advisories?

Accepted Answer

No beach is guaranteed to be unaffected during an advisory. However, some beaches are much less affected by runoff than others. Beaches with reef protection, no nearby stream mouths, and located away from urban storm drainage typically recover faster and receive less contamination. Man-made lagoons like Ko Olina and the Ala Moana breakwater-protected swim zone are often unaffected by advisories posted for open coast areas. During major Kona Low events, all beaches on an affected island can be impacted. Always defer to the Hawaii Department of Health for official guidance.

Question 3

Why are Ala Moana and Magic Island Lagoon recommended during brown water advisories?

Accepted Answer

Ala Moana Beach Park is protected by an offshore reef that creates a calm, shallow swim zone. The Magic Island Lagoon at the east end is further protected by a man-made breakwater. Both features limit the amount of nearshore runoff that reaches swimmers. Ala Moana is also lifeguarded and has restrooms, showers, and parking. When Waikiki has an active brown water advisory from Ala Wai Canal overflow, Ala Moana is often not under advisory because its water does not directly receive the canal discharge. Still, check the live advisory status before entering the water.

Question 4

How long should I wait after a brown water advisory is lifted before swimming?

Accepted Answer

The DOH typically lifts brown water advisories once visual discoloration clears. However, bacteria can linger in the water even after the water appears clear. The general rule is to wait at least 72 hours after rain stops and the water looks clean before swimming. In urban areas like Waikiki where the Ala Wai Canal is the contamination source, the canal can continue discharging for 24 to 48 hours after rain stops. For beaches near streams, check USGS stream gauges to confirm flows have returned to normal before entering the water.

Question 5

Can I still snorkel or dive during a brown water advisory?

Accepted Answer

The DOH advises against any ocean water contact during an active brown water advisory. This includes snorkeling, diving, and surfing. Offshore boat-based activities where you do not enter the water are generally considered lower risk. If you have a planned snorkel tour during an advisory, contact the operator. Most Oahu and Maui catamaran operators move tours to offshore sites or less-affected coastlines when advisories are in effect. Offshore snorkel sites like Molokini Crater or catamaran tours departing Ko Olina (west Oahu) are often less affected than south shore options.

Question 6

What makes a beach less risky during a brown water advisory?

Accepted Answer

Four factors reduce the risk of a beach during a brown water advisory: (1) Distance from stream mouths or canal outlets. Beaches with no nearby stream are less affected. (2) Reef protection. An offshore reef slows water exchange with the open ocean and limits contamination carried by currents. (3) Absence of urban storm drains. Rural or resort-developed coastlines typically lack the dense urban drainage systems that funnel runoff into the ocean. (4) Prevailing current direction. If the prevailing current carries contamination away from the beach, the beach is less affected. Ala Moana, Ko Olina Lagoons, Kapalua Bay, Wailea Beach, Po'ipu Beach, Anini Beach, Hapuna Beach, and Mauna Kea Beach all benefit from multiple of these factors.

Question 7

Are hotel pools affected by brown water advisories?

Accepted Answer

Hotel pools are chlorinated freshwater systems and are not affected by brown water advisories. All major Hawaii resorts maintain their pools to public health standards regardless of ocean conditions. Many resorts have saltwater lagoons or lazy rivers that are also generally unaffected. If you are staying at a Hawaii resort during an advisory, the pool is a reliable alternative. Resort concierges can also advise on which beach areas may be less affected.

Beaches Less Affected by Brown Water Advisories

Which beaches are least affected by brown water advisories?

Why These Beaches Are Less Affected

Where to Swim on Oʻahu During a Brown Water Advisory

Where to Swim on Maui During a Brown Water Advisory

Where to Swim on Kauaʻi During a Brown Water Advisory

Where to Swim on the Big Island During a Brown Water Advisory

What to Check Before You Go