Hi,
It can work ... or not, depending on a lot of things.
Even a fully aquatic newt can go out of the water from time to time (except for neotenic forms of course).
The newt species fully aquatic as adults have fully terrestial efts which can migrate between different ponds.
You'll probably have to build a barrier around the pond to avoid that, and enrich the surronding terrestrial environment with pieces of bark, compost... so that terrestrial youngsters will find food.
These recommandations are particularly critical in the case of a non native species (what is the legal contaxt ?).
An established pond usually harbors predator insects species like dragonfly larvae... and birds predators like herons.
A population of newts can compensate predation whith enough breeding pairs (several dozens) breeding each year.
If you have a limited number of newts to begin with, the risk of loosing them during the first year is high.