#flooding

Loss of vegetation and altered soil conditions can increase runoff, erosion, debris flows, sediment and downstream water-quality impacts after severe wildfire.

Drainage exposes carbon-rich peat to drying and smoldering combustion that can persist underground, resist surface suppression and produce prolonged smoke.

Specific streets and low points flood repeatedly in heavy rain — from clogged drains or drainage never sized for today's storm intensity — causing recurring property damage and access hazards that stay below the threshold for major capital fixes.

Turn flood-control drainage into water supply with spreading grounds, injection wells and green infrastructure that recharge aquifers, financed by a hypothecated parcel tax on impermeable area so revenue scales with the pavement causing the runoff.

Form a standing community Flood Action Group — backed by a flood charity — to systematically log flood hotspots, sustain engagement between events, and act as one coordinated voice to the councils and water companies that otherwise diffuse responsibility.

Install rain gardens, permeable surfaces and other sustainable drainage (SuDS) across the catchment to soak up rainfall where it lands, cutting peak runoff to overwhelmed drains. Most effective as a dispersed, upstream-weighted network.

Measure W, the Safe Clean Water Program, passed in November 2018 with ~69% voter support, creating a ~$280M/yr parcel tax on impermeable area, hypothecated to stormwater capture and quality projects. By 2024 more than $…

Since 2020 the Metropole de Lyon has run a "ville permeable" (permeable city) program, systematically disconnecting surfaces from the sewer network or depaving them so rain infiltrates where it falls. By 2025, 255 hecta…

China's Sponge City Program launched in 2015 with 30 pilot cities and over RMB 1 trillion (~140 billion USD) in cumulative national spending, deploying permeable surfaces, rain gardens and green infrastructure at scale.…

Nashville has pursued green-infrastructure flood mitigation — depaving, tree planting, and rain gardens — as part of its response since the catastrophic 2010 flood. This case study is included specifically for its hones…

Project Sponge supports community Flood Action Groups in Slough, facilitated by the National Flood Forum. Two groups operate: the Chalvey Flood Action Group (established 2023) and the HCB (Huntercombe, Cippenham, Burnha…

A purpose-built rain garden was installed beside the roundabout on Barnes High Street to reduce surface-water flood risk on paved urban areas. It absorbs excess water from storms and heavy rainfall, easing pressure on l…