If the application is in a non-freeze area, you can use 160 psi pressure pipe and do it your self. It can be buried in the same trench.
If it is in a freeze zone you can use PEX piping, which can tolerate freezing. It can still go in the same trench, it would help if you blew out the lines in the fall. It would also help if a plumber did this as he would have the crimping tool for PEX tubing. You can buy crimping tools now for around $65.00.
Water Treatment Specialist