The Alliance Hospitality Residence Inn was originally planned to receive visitors for the 2016 Republican Convention that was being held in Cleveland that year. However, the project was delayed due to settling issues on site. After two years of compression with high fill, the site was ready for construction.
The site utilized several small above ground storage areas, but engineers were unable to achieve all of the stormwater treatment goals above grade, so some underground storage and treatment was needed. The depth of the site was shallow and there were many utility conflicts. In addition, the municipality also required a filter system to meet water quality goals of 80% TSS removal per NJDEP.
To meet the storage goal, engineers selected a corrugated metal pipe system made from 2,181 LF of 36" perforated Aluminized Steel Type 2 providing 25,060 CF of storage. To meet the treatment goal, engineers selected a Stormwater Management StormFilter utilizing 18 cartridges. The StormFilter was constructed with a removable grate for easier long-term access.
The two factors that led the engineer to select the Contech solution were the complex layout of the site and the ability to meet local treatment requirements. The flexibility of the CMP system with varying lengths and ability to have stubs, elbows, tees, and risers incorporated into the system was a key component. The system had to be laid out to avoid utilities such as electric, sanitary, and water. The City of Middleburg Heights has unique treatment criteria and was familiar with the StormFilter from previous projects. The ability to treat 80% TSS per NJDEP was paramount in its selection.
Contech provided several iterations of drawings as the site evolved and the system layout changed. In addition, a preconstruction meeting was held on site to review the installation process and answer any questions the contractor had. Local Contech personnel also visited the site to check in on the progress and answer questions.
Installation was done in several phases by J Miller & Son, as the system was spread over multiple portions of the site. The contractor was able to install each part of the system and get it buried before moving on to the next section. The StormFilter was the last part of the system installed. The contractor had the hole prepared and quickly set the vault from the truck directly into place.
The Contech CMP underground detention system and StormFilter allowed for a site to be designed and approved per local regulations. The system was manufactured in a timeframe acceptable to the contractor to install during the winter. Lastly, the coordination of delivery of the various parts of the system allowed for a successful installation and project overall.