relay - Using Triac to control solenoid

I have to design a 4 relay or 4 triac switch.

First would control a 12V solenoid for water flow. Second would control 230V for a complete device which contains a small boiler as well.

After reading this: Triac versus Relay

It is still not clear to me if triac circuit like this:

http://www.instructables.com/id/Small-Triac-Switch/

are safe to use here. I read that triacs can break then let current flow (which would be catastrofic in my case at controlling the solenoid). This can never happen to relays, if the relay broke then that only means it wont turn the device on.

So can I rely on triacs for long time period (years)?