If it were me, I would make a claim on my insurance. The insurance company will subrogate the damages to those who are at fault. You paid for the insurance, you should use it. Ask them to make the claim under the liability portion of your insurance policy since you don't have flood insurance.
This appears to be a follow up to your earlier question. You won't work through this issue with piecemeal advice from this website. A review of your homeowner's policy is necessary, in addition to the remedies that have already been suggested in response to the earlier question. You just need to pull the trigger and make choices.
Make the homeowners insurance claim. If they decline to cover the loss, then you will have no option but to sue the construction contractor. In the meantime, hire a lawyer to immediately contact the construction firm to address the ongoing problem, as well as contact the Montgomery County permitting offices and get a building inspector out there pronto. There are strict rules and regulations regarding sediment and water discharge from construction sites. Although your homeowner's insurance may cover some of your damages, it may not cover all. Nor will your insurance company start acting on your behalf to stop future runoff events.