I do the same on the client-side to see if chunks are loader. Under worldObj.isremote.
worldObj.getChunkFromChunkCoords(this.chunkCoordX+ x, this.chunkCoordZ+ z).isChunkLoaded
If that returns false, the client will then send a custom packet to the server to send it a chunk.
Once the server has sent that chunk it becomes visible to the player. This chunk will appear on the client even if its more than 150 blocks away from the player.
I use a camera entity that spawns in client-side only that can allow a player to view any other entity away form the actual player.
So for instance if I have a plane that needs to fly way from the player, the camera entity will follow that plane. As you fly away chunks will load and appear around the plane. But once I get to ~150 blocks away from the player the plane disappears and stops ticking client-side (worldObj.isremote). It will still keep ticking on the server-side(!worldObj.isremote)