Designing with Swales

Swales are an impactful way to manage water runoff from various surfaces. This comprehensive article discusses the need for drainage swales, the benefits of designing with swales and bioswales, and explores how they promote sustainability. Plus, learn how Vectorworks Landmark can help bring swales to reality with water-conscious workflows and grading tools.

What Is a Swale?

Let’s start with a basic understanding of a swale. These shallow concrete channels with sloped sides manage water runoff from paved and unpaved surfaces, and they offer a more sophisticated solution than a traditional runoff ditch. A ditch is a landscape feature that is deeper than wide and designed to move water away quickly. Comparatively, a swale is a landscape feature that is wider than it is deep, intended to move surface water more slowly.

What Is a Bioswale? 

Bioswales build on the concept of a swale with added sustainability to prevent erosion. By using soil and plants, bioswales are permeable and allow water to infiltrate the earth. These eco-friendly features further slow drainage, encourage infiltration, and filter pollutants from stormwater – leading to improved water quality.

Bioswales represent a philosophy of working with natural water cycles and ecosystems, rather than merely removing water as quickly as possible. They provide both aesthetic and ecological benefits, such as supporting wildlife, improving microclimates, and helping cities address issues like urban heat island effects and flood resilience.

The Benefits of Swales

Swales bring many eco-friendly and sustainable benefits to a landscape. First, these features are proven to help mitigate flooding from stormwater by more effectively moving water and, therefore, reducing erosion over time. This allows water to reach the soil better and replenish groundwater.

How Bioswales Promote Sustainable Landscapes

Bioswales use their embedded vegetation to effectively filter and purify groundwater of pollutants and foster ecological habitats – contributing to both boosting overall sustainability and supporting urban cooling. Additionally, financial motivations, like impact fee discounts and tax incentives, encourage landowners to install green infrastructure such as bioswales, rain gardens, and other permeable surfaces.

Water conservation strategies, such as slowing down the flow of water, are prominent in many projects involving sustainable site design. Most concrete doesn’t properly manage the flow of water. After a heavy rainfall, water may pool or race towards the lowest points, which can lead to floods. A permeable pavement system, like an effectively implemented bioswale, absorbs water into the soil beneath the concrete and adds moisture to the soil in nearby plantings. This allows water to enter an underground drainage system, or perhaps recharge the water table in that area, and avoids floods.

Incorporate Bioswales into Your Design with Vectorworks Landmark

Of course, regulations exist that highly encourage or mandate the use of swales and bioswales for on-site stormwater management. But you may wonder how best to start implementing these features into your site design.

Vectorworks Landmark offers various tools to support designing water-efficient and eco-friendly landscapes with swales and bioswales. These easy-to-use tools simplify sustainability analysis by letting you define and manage more information so you can make smarter design choices.

Water-conscious workflows:

Charting Hydrozones – Organize the site into hydrozones to understand where water naturally collects and how it should be distributed. This helps match the right planting zones to water availability.

Water Budget Calculations – Run detailed water use analyses to ensure the design supports sustainability goals and local code compliance.

Plant Recommendations by Water Needs – The built-in plant database makes it easy to select species that align with each hydrozone, streamlining plant choice for drought-tolerant, native, or water-hungry areas.

Grading tools to design water retention:

Grading Objects – Precisely shape the terrain with grading tools to direct water into swales, slow runoff, and encourage infiltration.

Plant Objects – Place, tag, and adjust plant groupings directly in your design model while keeping their water requirements tied to the overall water budget.

Slope Analysis – Quickly assess grades across a site to identify ideal swale placement and ensure slopes meet accessibility and safety standards.

Surface Water Flow Analysis – Assess how water will move across the site so you can refine the bioswale’s size, alignment, and connection to other drainage features.

Ready to Get Started?

Explore Vectorworks Landmark to learn how to leverage these tools and features and elevate your sustainable designs – with cutting-edge software built for landscape and site design professionals.