A utility box assembly includes a housing structure having an open upper end, a first peripheral channel around the open upper end, and a second peripheral channel disposed below the first peripheral channel and inwardly therefrom. A first sealing element is seated in the first peripheral channel, and a second sealing element is seated in the second peripheral channel. A cover is configured to cover the open upper end. The cover has an outer peripheral portion configured to engage the first sealing element, and a downward-depending flange configured to engage the second sealing element. A liquid-tight seal is provided by the compression of the first and second sealing elements within their channels when the cover is secured to the open upper end of the housing.