Both are famous for dangerous shorebreak. One has significantly cleaner water — but at both beaches, wave safety matters more than bacteria.
Both Sandy Beach and Makapʻu have life-threatening shorebreak. Sandy Beach is the #1 beach in Hawaiʻi for spinal cord injuries. Waves break with extreme force directly onto shallow sand. These beaches are not recommended for casual swimming — they are for experienced bodysurfers and bodyboarders who understand the conditions.
Water quality is a secondary concern at both beaches. The shorebreak is the primary danger.
Makapʻu has significantly cleaner water. It rates 1/5 bacteria risk (very low) thanks to its isolated position at Oʻahu’s easternmost point — no streams, no urban drainage, no nearby development. Open ocean currents constantly flush the shoreline.
Sandy Beach rates 2/5 — still relatively low, but it sits closer to the Hawaiʻi Kai residential community and can collect urban runoff during rain events. No direct stream discharges onto the beach, but nearby drainage from the Maunalua Bay watershed affects the area.
Sandy Beach sits just east of the Hawaiʻi Kai residential community — one of Oʻahu’s largest suburban developments. While no stream or canal discharges directly onto Sandy Beach, the broader Maunalua Bay watershed drains the Hawaiʻi Kai area, and urban runoff from nearby streets, parking lots, and the golf course can reach the shoreline during rain.
The beach itself faces southeast with strong ocean circulation, which helps flush contaminants. On dry days, water quality is typically good. After heavy rain, bacteria levels can rise modestly — though the risk is much lower than urban beaches like Waikiki or Ala Moana.
Sandy Beach’s primary hazard is the shorebreak, not bacteria. The steep sand slope creates waves that break with tremendous force in very shallow water, causing neck and spinal injuries every year.
Source: DOH CWB advisories; City & County of Honolulu Ocean Safety annual reports
Makapʻu sits at the easternmost point of Oʻahu, at the base of the Koʻolau cliffs. Its geography makes it one of the cleanest beaches on the island:
• No streams or storm drains — the steep cliffs behind the beach mean no watershed drains to this shoreline.
• No nearby development — the closest residential area is Sea Life Park, and the beach is backed by undeveloped cliff face and the Makapʻu Lighthouse trail.
• Open ocean exposure — strong currents from the Kaiwi Channel constantly flush the shoreline with clean deep-ocean water.
The trade-off is the same as Sandy Beach: the shorebreak is extremely dangerous. Makapʻu’s waves break powerfully onto steep sand, and the strong currents that keep the water clean also create rip currents that pull swimmers offshore.
Source: DOH CWB; NOAA coastal data for east Oʻahu
At both Sandy Beach and Makapʻu, the shorebreak is a far greater risk than water quality:
Sandy Beach: The #1 beach in Hawaiʻi for spinal cord injuries. The steep sand slope causes waves to jack up and break with explosive force in just 1–3 feet of water. Swimmers caught in the impact zone can be slammed headfirst into the sand. City & County lifeguards make hundreds of rescues per year.
Makapʻu Beach: Similar shorebreak dynamics with the added danger of strong longshore and rip currents from the Kaiwi Channel. Waves can appear manageable from the beach but hit with unexpected force. The rocky points on either side of the beach create additional hazards.
If you are not an experienced bodysurfer, do not enter the water at either beach. Watch from the sand — both beaches are spectacular to observe. If you do enter, always swim near the lifeguard tower and follow their instructions.
Source: City & County of Honolulu Ocean Safety Division; Hawaiʻi DOH injury statistics
Both beaches are incredible for spectating. Sandy Beach is a favorite for watching bodysurfers and bodyboarders ride the shorebreak — bring a chair and enjoy the show. Makapʻu offers dramatic views of Rabbit Island (Mānana) and the Koʻolau cliffs.
For safer swimming with good water quality on east Oʻahu:
• Hanauma Bay — Sheltered bay with calm water and lifeguards. Entry fee required. Water quality is good on dry days.
• Waimanalo Beach — Long, gentle beach with calmer surf. Less urban runoff than Sandy Beach.
• Avoid swimming for 72 hours after heavy rain at any east side beach. See our rain safety guide →
• If water looks brown or murky, don’t go in — regardless of whether signs are posted.
Get notified when DOH posts new advisories for Oʻahu beaches.
Sign up for alerts →Hawaii DOH Clean Water Branch — Tier 1 beach monitoring, advisories. eha-cloud.doh.hawaii.gov
City & County of Honolulu Ocean Safety — Annual rescue statistics and shorebreak hazard assessments for Sandy Beach and Makapʻu.
Surfrider Oʻahu — BWTF supplemental water quality testing. oahu.surfrider.org
USGS — Maunalua Bay watershed data and stream gauge monitoring.
⚠️ Important Disclaimer
Safe to Swim Hawaii is an independent passion project — not affiliated with any government agency or monitoring organization. Assessments are based on publicly available data. They are not real-time measurements. “No DOH Alerts” means no advisory is currently posted — it does not mean the water was tested and found safe. DOH only monitors a fraction of Hawaii’s beaches, and some areas have no regular testing at all.
Always verify current conditions with the Hawaii DOH Clean Water Branch before entering the water.
When in doubt, don’t go out.