Sit down because I'm jumping right into some science. This is for your husband to help understand why the bridge idea is not going to help you. Normal soil has an open pore structure that allows air and water to pass through it. Inside this structure lives 10s of thousands of species of beneficial microbes which thrive on the open pore structure. These microbes are Mother Nature's invention. As it turns out the species of microbes living in swampy land are different from those living in dryish land (lawns). When you allow standing water to stand for several days, that cuts off the air flow to the beneficial microbes and their populations begin to decrease. If this happens enough, normal grass will thin out and stop growing. They will be replaced by swamp grasses like nutgrass and some others. So it is important to keep the water from pooling on your lawn. Back to the issue... If your community has an ordinance that says homeowners must drain all water from their own property and not allow it to cross over onto a neighbor's land, then all you should have to do is call your city code compliance officers and make them deal with it. If you live in the savage west, then you might have to do it yourself. Talk to your neighbors and ask them to berm up their land at the fence to keep the water on their side. Since they already dug the ditch, they are unlikely to bend to your wishes. So when that doesn't work, berm up your side of the fence and push their water back onto their property (see how they like having standing pools of water!!). Six inches of berm would normally be plenty. Planting a lawn in the spring is not the best idea, but if you really have to you have to. If you can afford sod, then that should be better, but if you were planning to seed, I would not spend a lot on seed for a spring installation. What will happen is all that new grass will find itself competing with crabgrass which also sprouts in the spring. Your grass seed will be less hardy than the crabgrass and will thin out in the summer heat. It is not uncommon to have a full crabgrass lawn by July. It is much better to seed new grass in the fall because crabgrass seed is not sprouting then. It also gives the new grass all winter and spring to develop heat tolerant roots. Now a word on forum etiquette. This is not your thread. The original poster had a problem with soil structure. Your problem is neighborhood drainage. You should have opened a new topic so people who want to help you don't have to read through someone else's problem from last year - which is really not your problem. I also suspect you will need some advice on planting your lawn (spring? or fall - either one). Now is the time to ask, so post a new topic! When you ask about planting a new lawn, please mention specifically where you live. The zone system is not good for helping with lawns, so give a town or zip code. And if you want more help on the neighborhood drainage issue, I would still post a new topic with your new questions. This forum seems to have a lot of opinions about neighbors '-)

You cannot know if that is a bad lawn or not. It's dormant. Here are the 1-2-3 steps of lawn care. Water deeply and infrequently. Deeply means at least an hour in every zone, all at once. Infrequently means monthly during the cool months and no more than weekly during the hottest part of summer. If your grass looks dry before the month/week is up, water longer next time. Deep watering grows deep, drought resistant roots. Infrequent watering allows the top layer of soil to dry completely which kills off many shallow rooted weeds. Mulch mow at the highest setting on your mower. Most grasses are the most dense when mowed tall. Bermuda, centipede, and bent grasses are the most dense when mowed at the lowest setting on your mower. Dense grass shades out weeds and uses less water when tall. Dense grass feeds the deep roots you're developing in 1 above. Fertilize regularly. I fertilize 4 times per year using organic fertilizer. Which fertilizer you use is much less important than numbers 1 and 2 above.

Fungal disease of some kind. How often do you water and for how long? How much rain have you gotten? Are you down in a low area or has that area been covered with brush or something? It looks like it was smothered or otherwise protected from sun and wind for a time. I take an organic approach to lawn fungal diseases. I use ordinary corn meal at a rate of 20 pounds per 1,000 square feet. Corn meal attracts another fungus which is predatory on the fungus causing your disease. That fungus is called trichoderma (try ko DER mah). It takes 3 full weeks before you see any improvement. That can be the longest 3 weeks of your life, but after that you should see less yellow and much more deep green. Corn meal is also an organic fertilizer so the dark green color will be very noticeable at the 3 week point. If you have used a chemical fungicide recently, then the corn meal will not work against the disease but it will definitely green up the grass. And yes this is the same corn meal you cook with. You can get it in 50-pound bags at the feed store. And no, it will not attract varmints. Seems like it would but it does not. It does seem to attract birds but they don't eat it. They just come and visit. You can apply corn meal any day of the year, rain or shine, or every day of the year, without fear of hurting anything. If you wan to take a chemical approach, I cannot help you. Our temperatures, humidity, and rainfall are usually outside the recommendations on most chemical fungicides. I gave up on them years ago when I found out how well corn meal works. On another issue you did not ask about: You are mowing your St Augustine much too low. Raise your mower all the way to the highest setting. It will take a month or so before all the grass gets tall enough to be mowed but it eventually will. Mowing it low favors the bermuda which is mixed in with it. Mowing it high can have the effect of choking out the bermuda. Tall St Augustine looks very lush.

Cultural solution first. Water deeply and infrequently based on the grass. When it looks thirsty (won't spring back after stepping on it or looks dry) then water at least an inch. Put a small can (tuna cans are ideal, but anything will do) in the area of the sprinkler so you know how much your putting down. Cut high with a sharp blade. Fertilize. It may be too hot for chemical fertilizer. If you don't have an aversion to Milorganite it would be ideal. Apply at the rate on the bag. Some may offer that fertilizing is wrong, but from your description the grass is weak and it needs food. Feed the grass and kill the weeds is how I see it. Fixing the weeds. Before you apply the Menards product read the label to see if it is effective on crabgrass. If not, then your local big box should have a product that would work. Bayer and Ortho are pretty good products. Hose end sprayer seems to work well. Same stuff should be available in granular if you prefer spreading, but liquid seems to work faster. Just follow the directions. Towards the end of August or first half of September you should plan on overseeding (cut grass short gradually, core aerate, apply new seed and fertilize). There are several threads with some great instructions on renovation. Patience. It will take some time to heal. Renovation this fall will be your best time to improve the lawn.