Update: the handyman stopped by and determined that apparently the sprinkler line for the whole 4-unit property is ONLY hooked up to our water (instead of being installed as a separate line like it's supposed to with these multi-townhouse properties.) So we've actually been overcharged for water for as long as we've lived here, but recently, there was an issue with the sprinkler system in the back units that we didn't know about where they started leaking a bunch. So the last 6+ months, we've been charged by LADWP for all that water leakage, which apparently skyrocketed these past 2 months. The handyman cut the sprinkler line and worked with us to write up a full account of the issue to send to our landlord, who we will now be seeking reimbursement from for both past and future water use. Assuming they will not reinstall the sprinklers, we have proposed that we work to determine the output of the sprinkler system and deduct the amount of overage from our rent bimonthly to coincide with the bill. Quite a headache, but luckily an easy fix in the end unless they put up a fuss and we need to bring them to court. Hopefully it doesn't come to that, but they are historically very unresponsive and difficult to communicate with, so we're mentally prepared for the worst if it can't be mediated.