The installation (c. 5×8 m; Fig. 2) was enclosed by walls (W104, W112, W114, W115; width c. 0.35 m, max. height 1.1 m) that survived to five courses high. The walls were built of kurkar and were set on foundations of small kurkar stones bonded with mortar. The bottom course of Walls 104, 112 and 115 was built of ashlars (average dimensions 0.2×0.5×0.5 m; Fig. 3), probably to ensure the stability of the installation. The upper courses consisted of fieldstones bonded with mortar that contained ground shells and organic matter. Pillars were found in each of the installation’s four corners; the pillars were built of fieldstones bonded with mortar and were meant to reinforce the structure. The inside surfaces of the installation were coated with a thick layer of light pink plaster, apart from W104, which was coated with gray plaster. The walls were abutted by a thick plaster floor (L113; Fig. 4) that was placed on a foundation of small fieldstones. The latter was set atop a bedding of large kurkar stones, some of which were partially dressed, which in turn covered a layer of hamra soil, devoid of finds.
Wall 114 collapsed outward at some point during the use of the installation (Fig. 5). At this point, it seems that the purpose of the installation was changed and it was then used as a furnace.
The pottery recovered from and around the installation included kraters (Fig. 6:1, 2), amphorae (Fig. 6:3, 4), baggy-shaped jars (Fig. 6:5, 6) and jugs (Fig. 6:7) from the Late Roman and Byzantine periods.
The plastered installation was evidently used as a water reservoir and was built between the end of the Late Roman and the Byzantine periods. It seems that this reservoir, like the one excavated c. 0.3 km to its east (HA-ESI 122), was only built after the construction of the Nahal Taninim dam, which resulted in a rise of the water table in the region. 
The water reservoir joins the industrial and agricultural installations that were exposed at the site and adds to our knowledge of the industrial-agricultural hinterland of the city of Caesarea in the Roman and Byzantine periods.