Some 'custom servers' will allow you to place static blocks, regular servers and/or scripted (Some scripted.) won't allow you. You can use omen to create some static water.
I do not recommend you to place static blocks in a normal server, Ive had a lava flooding with them, if you place a block besides a still lava, it becomes normal lava. idk about still water.
Or a way to add Water Blocks to mine server?
Thanks
-Ardril
Quality of output = Skill * Effort
Former #minecraft channel operator.
You'd either have to edit the map using OMEN (or oldskool hex!) or get some custom server software.