An evaporative heat exchanger including a plurality of parallel flow passages extending through the heat exchanger and together defining a first fluid flow path, and a plurality of substantially parallel stacked plates interleaved with the parallel flow passages. Each plate can have first, second, and third sets of flow channels, a first collection manifold adjacent to an end of the plate and connecting the first and second passes, and a second collection manifold. The second collection manifold can intersect the second set of flow channels and at least some of the third set of flow channels. The plate separates the first set of flow channels from the second collection manifold.