Irrigation System
If you must install an automatic irrigation system, install one with a rain sensor.
Choose sprinkler heads with a larger droplet size to reduce wind drift and where possible place the sprinkler heads on the edges of garden beds facing inwards. This will achieve the best coverage of the garden and reduce overspray on to hard surfaces such as roads.
Keep water pressure as low as possible to reduce waste through wind drift. Use "dripper sprinklers" where possible.
Use soaker hoses on narrow garden beds such as beside driveways to reduce runoff on to hard surfaces.
Use a simple and inexpensive tap timer on manually operated sprinkler systems.