Leo Urban, Landscape Architect, Leadership in Energy and Environmental Design Accredited Professional at Urban Associates Inc. has completed a community renovation project in Highland Beach, Florida.
The entrance was constructed over 17 years ago and lacked curb appeal needed to protect existing home values and changing architectural styles. The roadway flooded after each rainfall because of the minimal surface grades and localized settlement problems. Urban Associates, Inc. was hired to prepare design plans, cost estimates, bid documents, Town and Florida Department of Transportation permits and construction observation services. Mr. Urban helped the community obtain a variance to construct taller gates and columns at the entrance. The existing gate and column heights were not in scale with the 50-foot Royal Palms and two story buildings. He secured the necessary driveway curb cut and landscape removal and replacement permits from the Florida Department of Transportation.
The entrance renovation included a new gate operating system, new pavers, stone veneer walls and columns, cast stone column caps and wall coping. Additional improvements included LED post and wall lights, sign improvements and replacement of shrubs with flowering shrubs and perennials.
The existing valley gutter was removed and replaced with a 7.5-inch depth permeable concrete gutter to solve the street drainage problem. Mr. Urban designed a stone reservoir wrapped with geotextile fabric below the permeable concrete gutter. He tested the percolation rate of the existing soil with an in-house infiltrometer and determined the recovery rate for the stone reservoir will be only 18 minutes for the 25-year rain event. His design eliminated surface flooding and substantially reduced the amount of stormwater runoff sheet drained and piped to the existing on-site retention basin. By directing and filtering the surface runoff through the stone reservoir and sub-soil the water quality is greatly improved before it reaches the ground aquifer. The amount of potable water needed for irrigation has also been greatly reduced due to the exfiltration of surface runoff into the sub-soil of nearby landscape areas.
The permeable concrete gutter with a stone reservoir for stormwater storage has successfully solved the roadway drainage problem. After major storms including two hurricanes that followed the east coast of Florida, there has not been any prolonged flooding of the street. The success of this project has won the interest of neighboring communities to look at this innovative design solution to solve their street drainage problems.