Objectives
Demand for the community resources provided by the Elkridge campus of the Howard County Library System had outgrown the size of the facility. The property site offered adequate space for expansion, so the county embarked on a $28.9 million project to modernize the facility and increase the footprint to more than twice its existing size.
The property had an existing stormwater management facility constructed in the early1990s that included traditional storm drains and a pond. Since original construction, the county had adopted new stormwater management requirements. Any new pavements needed to be compatible with the older system while still in compliance with these newer guidelines.
Solutions
Parking spaces in the main parking lot were designed to be permeable. Joint openings between the pavers ranged from 7 to 8 mm and were filled with a highly permeable filter aggregate (ASTM No. 9 stone). The open-graded base of aggregate beneath the pavers were designed to act as a reservoir to hold stormwater like a detention basin until it could be released back into the environment, minimizing runoff from the property.
Results
The new facility opened in 2018. Due to the infiltration rates of the PICP, expansion of the pond was not required, and the new combined systems are functioning together as designed.
Team & Location
Owner: Howard County Library System
Designer: Grimm + Parker
Producer: Belgard
Installer: Imperial Stone Paving