With high annual rainfall and a splendid aquifer, Costa Rica has some of the purest, freshest tasting drinking water in the world -- rivaled only by Switzerland. Water treatment plants are rare outside the Central Valley (population center).
Water quality is rigorously monitored by local municipalities. That means you are almost never at risk even when drinking directly from the faucet.
Unless a hotel or restaurant instructions you to drink bottled water, feel secure drinking what the locals drink. No Montezuma's Revenge here.
First, to toot our own horn, Costa Rica has achieved 100% carbon neutral electricity, 90-95% from hydroelectric plants. We export a portion of our generated power, and we continue to invest in alternative energy projects - wind, solar, geothermal thermal. It's Costa Rica's commitment to our people - to be the world's first carbon neutral nation by 2021*.
* http://www.climateactionprogramme.org/news/costa_rica_pledges_carbon_neutrality_by_2021
Electrical service in Costa Rica is identical in all ways to the USA -- same voltage, same plugs and outlets. If your equipment works in the USA it will work in Costa Rica.