Residential on Marengo Avenue

Single-family residential fire rebuild in Altadena following the Eaton Fire. The 0.229-acre lot drains west to east with part of the rear lower than the rest of the property. The site includes a single-family house, a detached garage in the middle of the lot, and an ADU at the rear. A new driveway apron was shifted slightly north of the existing one, with the driveway sitting 2 feet higher than the grade around the house. Between the house and garage, the lot steps down to the rear sideyard which continues to a pool at the far rear.

This project specifically requested a large underground tank to hold water in case of another fire. We sized a 1,325-gallon underground tank at the rear of the property to capture and store fire protection water. LA County required that overflow from the tank be handled for stormwater, so we installed a plastic-lined rain garden offset 5 feet from the property line at the lowest point of the lot to accept overflow when the tank reaches capacity. A combination of downspouts and trench drains throughout the property pipe into this underground tank. A short new wall was added between the driveway and house to address grade differences. Keeping slopes at or under 5:1 (20%) meant the project qualified as a drainage plan rather than a full grading plan, which simplified LA County approval.