Is my HOA Responsible for damage done to my driveway and sewer line by a tree that it owns and will not let us touch?

Don't act unilaterally. Judges and retired judges who act as arbitrators hate self-help. Have you sent a written (not email) notice to the HOA about the tree and asking the HOA to fix the problem i.e. remove the roots or the tree? That first step is mandatory. The Davis-Stirling Act requirs your HOA to provide a process where the Board appoints someone to meet with you and try to work it out. If you ask for it, the HOA must provide it. If that doesn't work, try offering third party mediation. Faster and cheaper than a lawsuit or arbitration. Your CC&Rs might require the HOA to participate Next, check the procedure for resolving disputes. Most require arbitration. Sometimes there is an exception when you sue to enjoin a nuisance. You should have a real estate attorney familiar with CC&Rs and the Davis-Stirling Act review your CC&Rs and any other governing documents. Before starting a lawsuit or arbitration, you want to be very sure that you will win. The prevailing party is entitled to recover its attorney fees and expenses. Lawsuits are very expensive. If you lose and don't pay, the HOA can collect by foreclosing on your house, evicting you and selling the house. Dana Sack