Where are you in NoCal?

What kind of grass do you have?

What is your watering schedule? How often and for how long do you water?

I've been trying to find out the exact type of grass - all I get is "tall fescue" from the installer. we were on 3x/week for 7 minutes - being more aggressive with water has started to help. I just can't figure why some spots grow great and right next to them, not so great.

Good start on answering the questions. Where do you live in NoCal?

San Joaquin County - lots of sun and mild temps

Perfect. You are far enough inland that watering is an issue for tall fescue. The first rule of gardening is to plant plants adapted to your area. Fescue is not one of those plants for your area. You should transition or renovate to a warm season type of grass. Suggestions include UC Verde Buffalograss, TIF 419 bermuda (a hybrid), St Augustine, or zoysia. Those are in order of water savings ability. If you want to have nice looking grass all the time, every lawn will need about 1 inch of water per week in the heat of summer. Buffalograss and bermuda will come back from zero watering better than St Aug or zoysia, so if you have watering restrictions that only allow watering once a month, you might want to go with those. Only St Augustine will survive in the shade, so if you have trees or shrubs in the area, you could just standardize on that species. Now is a good time to install a warm season lawn. Most of them come as sod, but the UC Verde comes as plugs that spread fast. If you decide to go with a new grass, let us know and we can help you get it down with good results. Whatever you do, do not rototill to prepare for the new sod.

Watering: Deep and infrequent is the mantra for watering. Deep means 1 inch all at one time; not spread over a week. You can measure an inch by placing cat food or tuna cans around the yard. Be sure to put cans in the good spots and the bad spots. Turn on the sprinklers and time how long it takes to fill all the cans. That will be your watering time from now on. Infrequent depends on temperature. If the cans in the good spots fill long before the cans in the bad spots, then you have sprinkler head issues. As for frequency, for temps below 70 F, deep water once a month. For temps in the 70s, water once every 3 weeks. For temps in the 80s, water once every 2 weeks. For temps in the 90s, deep water once every week. For temps in the low 100s, deep water once every 5 days. For temps above 110, water every 3-4 days.

Thanks everyone - we've been able to see some good recovery simply with extra watering (and a little sprayer "grow" blue crystals) - once it's going strong again it won't require that much to keep going. Since it's a 1 year old new lawn we aren't going to even consider replacing it, but will start less frequent deep watering once it's back.