We don't drink the local water when we travel to Mexico or parts of Asia or New Jersey .

What's the water safety situation in CR?
Also, is it pretty safe to eat at roadside stands, etc.?

the "unofficial" word is yes it's OK to drink the water.
We heard that time and again when researching our June trip. We had no problem drinking the local water

However...one tourist on one of our hikes had to return to "base" with intestinal problems. Maybe we were just lucky.

Let's see what the real CR experts on this board tell us.

I drank water all over Costa Rica and had no problems

We also drank the water all over CR and had no problems. (but I wouldn't call my self a CR expert) We spent 10 days there and ate salads everyday and drank local water. At least it's safe in the Central Valley, around Arenal and in Manuel Antonio.

At Bosque del Cabo on the Osa peninsula, in Alajuela and in Manuel Antonio, I filled my water bottle from the tap, ate salads, ice cubes in the drinks, etc and never had any problems. I've only eaten at 3 soda's and it was some of the best food ever, not to mention friendly & welcoming. One was actually half soda, half house. Felt odd at first walking thru their living room! But the food was delicious even if I couldn't identify all of it!

Tab water is generally safe to consume if it's collected from wells you might ask around first and check if there are any bottled water dispensers first.

My husband and I both have very temperamental digestive tracts, but we were told not to fear in Costa Rica, even after we both had significant trouble in Jamaica. I am pleased to attest that the water from San Jose to Arenal to Tamarindo was no problem for us. We drank it, brushed our teeth with it, and ate tons of fresh delicious produce washed and prepared in it and never had an ounce of trouble.

As for the roadside stands, I agree that some of the best food I've eaten in Costa Rica (and elsewhere for that matter) has come from these small home-cooked establishments. The local flavors seem to be much more vibrant in these places than in those that temper their cooking for American palates. Try out the little spots and enjoy the adventure of experiencing a different culture on a more personal level.

In the many trips I've made....15, or is it 16? I have never had a problem with drinking the water anywhere, nor a problem with any of the food.
I do know some however who have had some problems and attribute those slight problems to too many Imperials or too much tropical fruit they are not used to eating at home!

We just returned and drank the water nearly every where we were (Alajuela, Osa, etc.) and didn't have much trouble. My daughter and I both had a little trouble on our return home, but I attributed that to a few gulps of river water on a white water rafting trip. The nurse in charge of international travel at our local university suggested we take a preventive dose of Cipro (500 mg 2 x day for 3 days) in case we had intestinal upset. I took 1 cipro on two successive days, and that knocked my upset. You might check with your health care provider, keeping in mind that Cipro can cause problems with you Achilles tendon and other cartilage as I understand it. Many places filter their water to make it safe for tourists, so you can also ask if the water is filtered.

Just returned from Arenal/La Fortuna area and MA/Quepos area. We drank the water with no ill effects. The water was quite good tasting also. As far as the roadside open-air restaurants, we ate at many and the food was very good everywhere. I can report we returned home with no diarreha. I cannot say the same about our trips to Mexico. Anyway, have no fear. I think all is good.