The posted coordinates will take you too Ahalanui Beach Park. You may want to bring a swimsuit and towel and enjoy the water afterwards. Even if not swimming you may get your feet wet on this earthcache. To get there from Hilo travel south on Highway 11, Mamalahua Hwy till the Keaau Bypass turnoff. Turn left onto Highway 130 and travel 12 miles to a left turn onto Highway 132. Head down Highway 132 curving left after 2.8 miles staying on 132 for another 5.1 miles until you reach junction 137. Turn right onto Highway 137 for another 2.7 miles and watch for Ahalanui Park on the left. It’s a long twisty road there but well worth it. Please note that the Park does close for maintenance every 2nd Wednesday each month.
The Ahalanui Park is home to a geothermal heated pond. So why is the water heated? The rainwater that percolates into the ground eventually hits a salt water table. The fresh water is less dense than the salt water and will float on top and create the ground water table. In Volcanic areas, the ground water will travel through rocks heated by magma. The heat is transferred to the water and will be become very hot. As the water, travels away from the hot spot towards the shoreline it starts to cool and mix with the costal seawater creating the warm springs. Warm springs like these are common along the Puna coastline.
These ponds are partially man-made and natural formation. The bottom of the pool is sand and mud and has a slight sulfur smell. The water is brackish but very clear and fish often swim along with the visitors. A small inlet separates the pool from the ocean and allows the fish access to the pool. This area is a very popular swimming area among locals and tourists. Usually there is lifeguard present. There are warnings that if you do have an open wound that you should not enter the pond because of the risk of infection. If in doubt check with a lifeguard before entering the pool.
To log this Earthcache you must do the following:
- 1. Take an average tempature reading of the water from 3 different locations, the temperatures varies through out the pool. We suggest taking readings at the stair locations for ease. Email your answer but do not post it in your log. (You will need a thermometer for this part. A cheap digital thermometer from a drug store will work.)
- 2. Record the the high tempature of the day you visited the site. Also include this in your email only.
- 3.OPTIONAL Take a picture of you in front of the pool with your GPSr visible.