Putting Kolter Building Concerns to Rest
by Jennifer Claridge
Meyerland residents, many rebuilding after Harvey, have been watching the new Kolter Elementary building emerging on the northern edge of Godwin Park. While the families with children who attend Kolter look forward to the neighborhood elementary back in the neighborhood, nearby homeowners cannot help but wonder if the new building and what appears to be fill coming onto the campus increase flooding risk.
Living in Meyerland has become synonymous with knowing the flood-related building codes regardless of professional affiliation to the building trades. Building codes for homes and commercial buildings do not allow fill dirt underneath a building displacing water or impeding its flow underneath the building, much less to be brought from offsite. Yet even casual passers-by notice dirt is being brought in and piled to go underneath the building. Those concerns were taken to the architect of the Kolter campus. The Houston Independent School District (HISD) explained how they arrived at the new design.
The primary building code governing the design, including the foundation and fill dirt, is the 2012 International Building Code with Houston Amendments. The design was modified to meet the Houston’s New Flood Plain Ordinance (Chapter 19) which went into effect on September 1, 2018. The ground floor will be elevated on a pier-and-beam type foundation with minimal obstructions underneath to allow storm and flood waters to flow relatively freely underneath the building. The new structure is not expected to increase flooding or change the flood water flow pattern on adjacent properties.
The soil brought to the site is for areas where more load-bearing capacity and less differential movement are needed. It is a select fill (soil mixture of lean clay and sand with little to no organic material). It is expected to be more absorbent and hold more rainwater than that existing onsite. Fill will be used to raise the bus and parent drive lanes to the height of the first floor. For every cubic yard of fill brought on site there is a corresponding cubic yard of soil being scooped out to lower the elevation in another area of the site. This approach is called a “balanced” cut and fill strategy required by city ordinances. By its own measurements it is scraping away 300 cubic yards more than it is bringing onto the land.
Many are concerned more impervious space is being poured than the old campus had to accommodate the contemporary community. For instance, a dedicated carpool and bus lane, parking, and a larger footprint of the building. The designers explain those concerns were addressed by meeting current regulations, designing a two-story building so it can be larger without greatly increasing the footprint. The previous building with temporary buildings had a footprint of approximately 50,870 square feet. The new building will be 94,969 square feet, but its footprint will be 60,552 square feet.
According to HISD, the new building will have carpool lanes for traffic flow and safety moving car and bus queuing off adjacent streets. The amount of impervious surfaces will increase by 10%. The increase will be offset by the retention capacity in the new onsite storm drainage piping. HISD worked with the city’s Code Enforcement Division, including its Flood Plain and Storm Water groups, to ensure all drawings, calculations, and specifications meet city detention requirements.
Contrary to rumors, there will not be detention storage underneath the building nor is a pond planned. Instead, there will be a storm water management and retention system. The large structures being placed underground are large storm water drainage piping equipped with flow restriction devices to retain storm water before strategically releasing it into the city drainage system, acting as retention to guard against overwhelming the system. This retention system is being combined with site grading, storm water drainage inlets, and measures to deter rainwater runoff to adjacent properties.
Lastly, rain can start during a school day so the building could keep the students and staff safe if flood waters began rising. Owners of nearby homes may look to the new elevated building as a nearby refuge. HISD plans include such contingencies. Though the school is not designed to serve as a long-term emergency shelter, the first floor is being built a foot above the 500-year base flood elevation established by the Federal Emergency Management Agency. The building is designed to meet requirements for withstanding storms and high winds. HISD has an agreement with the Houston’s Office of Emergency Management to allow several facilities to be used as Refuges of Last Resort.