PLAT insights ｜ Designing for Extreme Downpours
October 8th, 2026
Berkeley, CA
In environments increasingly shaped by intense rainfall, the collection, retention, and reuse of stormwater are fundamental to landscape design. By integrating ecological stormwater management, water reuse, naturalistic planting, and water features, stormwater infrastructure becomes more than a technical necessity. It becomes an integral part of the landscape and the experience of place.
Responding to Heavy Rainfall
Rather than treating rapid drainage as the sole response to intense rainfall, the landscape is designed to receive, slow, and manage water across the site. Roads, topography, planting, and open spaces work together to accommodate changing water levels and distribute stormwater management throughout the landscape.
Water landscape integrating stormwater detention, circulation, and spatial experience
Keeping Water in the Landscape
Runoff from roads and paved surfaces is directed into planted depressions, linear retention areas, and basins of varying depths. Topography, planting, and engineered soil media work together to slow water movement while supporting sedimentation, filtration, and gradual cleansing.
Dry creek beds, pocket retention areas, and stormwater ponds are connected along the natural topography to form a distributed and continuous water network. Rather than concentrating runoff within a single detention facility, water is progressively captured and managed throughout the landscape, allowing stormwater infrastructure to become integrated with roads, walkways, and planted spaces.
Dry creek stormwater collection system
From Detention to Rainwater Harvesting
Ecological stormwater systems help accommodate increased runoff during periods of intense rainfall, while water reuse extends the role of captured water beyond the storm event.
Collected and treated stormwater is returned to landscape water features through a recirculating system that connects water elements, overflow weirs, and basins at varying elevations. Changes in topography, gabions, and planting define the movement and rhythm of water, creating a continuous system of retention, collection, reuse, and recirculation.
Water movement becomes more than a drainage process. It becomes a visible and experiential element of the landscape.
Ecological water corridor shaped by changes in elevation
Naturalistic Character and Ecological Habitat
A naturalistic landscape is shaped not simply by the appearance of nature, but by the integration of materials, planting, hydrology, and topography in response to environmental conditions.
Natural stone, gabions, and gravel define water edges, grade transitions, and dry creek beds, reducing the need for extensive hard-edged channels while creating more adaptable interfaces between land and water. Plant communities respond to varying hydrologic conditions: areas that regularly receive water support species tolerant of periodic inundation, while zones with greater fluctuations between wet and dry conditions are planted with more adaptable species.
Layered planting of varying heights and densities, combined with species that provide food and habitat value, supports insects, birds, and other wildlife. In this way, stormwater spaces perform simultaneously as water infrastructure and small-scale ecological habitats.
Layered planting creating a naturalized water landscape
Water Features as Part of the Environment
Water features are not introduced as decorative elements, but emerge as visible expressions of the larger stormwater management and reuse system.
During dry weather, creek beds, planting, stone, and water form part of the everyday landscape. During rainfall, runoff moves with the topography into planted retention areas, where it is slowed, filtered, and collected before returning to the landscape water system.
As rainfall and water levels change, the landscape shifts in character and experience. Roads, topography, planting, water, and habitat are no longer treated as separate components, but operate together as an integrated landscape system designed to adapt to periods of intense rainfall.
Ecological water landscape integrated with streets and everyday spaces