RDN Rain Garden

A rain garden is a specifically designed landscaping feature that helps manage rainwater run-off (sometimes referred to as stormwater) from roofs, driveways, sidewalks, and other impermeable surfaces. During a storm, rainwater is slowed, captured, and slowly filtered into the soils of a rain garden, rather than running directly into a ditch, storm drain, lake, river, creek, or stream. Rain gardens mimic the hydrological cycle in which water is cleansed of pollutants as it percolates into the ground to replenish the water table. Rain gardens are important green infrastructure solutions that can be adopted by local governments, businesses, organizations, communities, and households!

Green infrastructure refers to a network of natural and constructed features designed to manage stormwater, reduce urban heat, improve air quality, and provide ecological and social benefits within urban areas. Green infrastructure, such as rain gardens, bioswales, permeable pavements, green roofs, and urban parks and green spaces, utilize natural processes to address environmental challenges and promote sustainability.

How a rain garden works

A rain garden is a shallow depression in the ground filled with native plants, shrubs, and trees, that is positioned strategically to capture rainwater and allow it to slowly infiltrate into the soil.

The benefits of rain gardens:

Stormwater Management

Rain gardens reduce the volume and velocity of stormwater run-off, which helps to prevent erosion and flooding.

Water Quality

As rainwater percolates through the soil and plant roots, pollutants and sediments are naturally filtered out, improving water quality before it reaches groundwater or nearby water bodies.

Biodiversity

Rain gardens provide habitat for various wildlife, including birds, butterflies, and beneficial insects, contributing to local biodiversity.

Aesthetics

Rain gardens enhance the visual appeal of landscapes with a variety of natural colours and beautiful seasonal blooms!

The RDN's Rain Garden

The Regional District of Nanaimo (RDN) is home to a rain garden in need of care. Located on the property of the RDN's Administration Office on Hammond Bay Road in Nanaimo, the RDN's Rain Garden is currently undergoing an upgrade so that it functions properly to slow, capture, and filter stormwater run-off from the surrounding landscape, parking lots, and roadways. The RDN has contracted a local landscaping firm to amend the existing rain garden by removing turf and invasive plants, installing fresh soils and mulches, and planting native plants throughout the site. 

The goals of the RDN's Rain Garden project include:

• Amend the existing rain garden so that it properly functions to slow, capture, and infiltrate rainwater run-off,
• Create a rain garden demonstration site to bring public awareness to rain gardens and other green infrastructure,
• Learn more about green infrastructure installations of this type to inform the Demonstration Site & Interpretive Signage funding program.

Track the progress of the RDN's Rain Garden project:

Current State

The RDN's Rain Garden currently does not function as a rain garden should. The 22-meter-long swale runs along Hammond Bay Road on RDN property. The depression of the rain garden is covered primarily in turf grass, which covers hard-packed and nutrient-poor soils. Some invasive species, including English Ivy, surround the site. This reduces the opportunity for water retention and infiltration within the rain garden. Instead, rainwater run-off captured by the rain garden currently pools in the depression before entering stormwater drainage on site. 

 

 

Plan

The RDN plans to upgrade the rain garden so that it functions properly and serves as a public demonstration site by:

• removing turf grass and invasive species
• amending the soil and installing mulch
• planting native plant species throughout
• installing pathways and interpretive signage for public awareness and engagement

 

Installation

Landscaping work has begun on the rain garden! Through early May, excavation of the turf and invasive species, shaping and sloping, and rock installation will be completed, followed by the installation of fresh soils and organics. The landscaping crew is taking care to salvage and re-purposing as many plants as possible while protecting the established trees on site. Later this spring, native plant species will be planted throughout the rain garden.

 

 

Completion 

Coming soon!

Please check back again to stay up to date on the progress of the RDN's Rain Garden project! Contact waterstewardship [at] rdn.bc.ca with any questions.