For much of the way, Imperial Highway is signed as State Route 90. A de facto freeway portion of the route in Yorba Linda is also known as the Richard M. Nixon Parkway. The portion in Los Angeles County is located about one mile north of, and runs parallel to, Rosecrans Avenue.
Are areas of your lawn bumpy and uneven? When you walk across these areas does the soil sink or feel soft? If so, some type of soil dwelling critter is probably the cause. During winter the activity of moles, earthworms, and mole crickets can cause mounds and tunnels in lawns that result in uneven or rough patches. To fix these problem areas you must first diagnose which critter is causing the damage. Earthworms.
If the lawn has brown spots of grass or balding areas, it is possible that these lawn conditions are caused by grubs. Prior to planting new grass seeds, remove any grubs from the soil. An easy way to confirm a grub problem is to turn over the soil 3 inches deep to expose any existing grubs or eggs. If they are discovered in small amounts, manually remove them from the soil to halt the continuation of their life cycle and reproduction.