thank you for the answer. but the 24-plex has a total land of

0.21 acre (the 116-year-old building grandfathered in with no requirement for parking), that is 8580 sqft. I guess the lawn is less than 1000 sqft. that accounts for <5 ton per month. Assume the maintenance overwatering, that should account for <30 ton per month, which is 10% of the 300 ton increase.

My concern is whether there is a leak in the main pipe that was caused by the basement construction. Or sabotage.