Freno™ Rain Garden

Manufactured by Midwest Products Group

Patent Nos. 8,157,991; 13,447,733; 8,596,909

Freno is an innovative segmental wall and curbing system designed to easily incorporate rain gardens into urban settings, helping to reduce run-off, improve water quality and enhance streetscapes.

Developed by HOK’s Paul Wilhelms along with Matt Snelling and Jim Fetterman (HOK Alumnus) for HOK Product Design, Freno – the name is Latin for “curb” or “restrain” – offers an alternative to traditional cast-in-place methods, providing a higher level of quality and more durability at a lower cost in less time.

Municipalities across the county are struggling to deal with the massive amounts of stormwater runoff generated from impervious surfaces associated with public and private developments. When this runoff overloads existing water treatment infrastructure, the often-polluted rainwater is discharged directly into our rivers, lakes and oceans.

Traditional water treatment methods are expensive and energy-intensive, prompting many communities to turn to rain gardens as a decidedly low-tech, but highly effective approach to stormwater detention and treatment.

Rain gardens improve water quality by catching rainwater with plants and soil, thus reducing stormwater flow rate, volume, temperature and pollutants. The rain gardens process water naturally, allowing it to infiltrate and recharge groundwater aquifers.

In recent years, many organizations have built rain gardens to address stormwater runoff in a way that is extremely efficient, easily maintainable and aesthetically attractive. Yet these installations typically consist of cast-in-place concrete enclosures that require extensive over-dig, formwork and labor while being subject to variable levels of finish quality.

Freno’s designers had a better idea. Snelling, Wilhelms and Fetterman conceived a precast concrete “kits of parts” system – a modular urban rain garden that provides high levels of finish, durability and flexibility. It costs less and can be constructed much faster than a comparable cast-in-place system.

The Freno system is made up of three basic shapes that, much like giant Legos, can be arranged in a limitless number of configurations. Unlike a cast-in-place basin that can require weeks to build, the Freno system can be installed without the need for over-excavation, trench supports or formwork – and without concerns about how the weather will affect the quality of an installation.

Freno is currently available in three standard colors. It can be specially ordered with custom color and aggregate that complement the site and its landscape features.

Freno is manufactured with sustainability in mind. Its precast units are produced in a controlled factory environment, and all material waste is recycled. The concrete design mix uses non-toxic colorants. Using up to 8% fly ash content reduces the amount of cement used in the product. The multiple manufacturing sites combine to create a distribution network that provides delivery within a 500-mile radius to two-thirds of the United States.

Freno Brochure

Landscape Architecture Magazine, June 2011

Watch a video about Freno

Freno Website

Concrete Products Group Website

More about rain gardens:

Sustainable Streets Guidebook
(San Mateo County, California)

Stormwater bioretention benefits

How to size a rain garden (includes links to Microsoft Excel spreadsheets for sizing with or without infiltration)