Archaeology Update — Learning More About the Construction of the Church’s North Wall

Work is ongoing with the installation of the safety bollards around the perimeter of the Plaza. If you visit today, you will see areas being worked on and previously worked on areas open for pedestrian use. Over the past several weeks there have not been significant archaeological finds in the safety bollard locations since much of the impacts are within a zone of concrete and caliche base. This means that there has been little work occurring within intact soils that could contain artifacts.

Archaeological work associated with the preservation of the Church and Long Barrack continues. Six excavation units were active during the week; two on the south side of the Church, two associated with the north wall of the Church, one located on the south side of the Long Barracks, and one small unit located at the threshold of the Church. In addition, the archaeologists worked on backfilling a couple units that have been completed and fully documented.

On the north side of the Church, archaeologists are uncovering interesting information about the construction of the north wall, although the unit is riddled with old utility lines. During the week, a cast-iron pipe and a ceramic pipe were uncovered at approximately 31 inches below datum. The cast-iron pipe may be an old water line, whereas the ceramic pipe is an abandoned sewer line.

Even though there is quite a bit of disturbance from these utilities, the archaeologists are still able to observe the foundation kick-out, and have observed an alignment of stone that appears to be running perpendicular to the north wall of the Church. It is too soon to determine if the stones represent an alignment and, if so, what the purpose of the alignment could be.

Excavations on the south side of the Long Barracks have continued. Excavation Unit 9B is larger than the rest of the units to allow for better observations of the original foundation, the possible seam between the original wall and possibly reconstructed section, and to hopefully gain a better understanding of the cobbled stones that were observed in the base of the unit on the interior of the Long Barrack.

Excavations on the south side of the Church have encountered dark clay soils that contain very little artifacts. Archaeologists are reporting that they are mostly encountering snail shell, and stone flakes, likely representing the very early mission period or even prehistoric use of the land.

A small unit was excavated in at the threshold of the Church door in search of the threshold stone. Excavation occurred in the mornings prior to the opening of the Church to the general public as not to impact access to the Church. The historic architects were hoping to find a solid stone representing the entry way into the Church. Excavations revealed that the threshold in the area that was opened consisted of several stones placed in a lime slurry mixture acting as the mortar which is similar to what has been seen in the construction of the foundation. Archaeologists plan to complete their documentation and close the unit.

Phase I archaeology permit applications were presented to the Texas Historical Commission during the week. The THC approved the archaeology permits with a few clarifications. Archaeological work associated with the improvements to the southern portion of Alamo Plaza and along Crockett Street will be able to proceed.

Archaeological investigations associated with the installation of the safety bollards and the investigations associated with the preservation of the Church and Long Barrack will continue in the following week.