Save for Rain-Free Days

Saving Stormwater to Banks More than Greenery

Updated October 2026. By Cassy Aoyagi:  We like to think of each rain drop saved as a drop earned. With Californians paying some of the highest water bills in the county, those drops can also be (more than) pennies earned. Greener landscapes, safer cities, money, time, and our peace of mind flow-in along with those savings.

Let’s explore what we gain when we bank our stormwater together.

Much of Maravilla Ranchito‘s year-round greenery is fueled by sinking stormwater.

Sink Water, Save Greenery

Once upon a time, during our last significant drought, incentives focused on water collection via rainbarrels and ciserns. Smart. Collecting just the first quarter inch of rain from a 1000 square foot roof can produce as much as 150 gallons. In real terms, this is generally enough to support container gardens, keep a birdbath filled, or extend the timeline before turning the irrigation back on in spring. What is captured is, of course, limited by the size of the barrel.

While many water sinking features have visible rock and stone, it is the topographical shift and underground structure that help water percolate into the groundwater table. For a greater aesthetic, riparian native plants can thrive in bioswales and vernal pools.

There is an even better way to save. A bioswale’s capacity is nearly limitless. Greater tree health, greener landscapes, and safer cities flow from sinking water into our common groundwater accounts. About now you may think I’m suggesting you sacrifice for the common good? Nope! What’s good for LA is good for your garden – especially our native trees. When water sinks, it encourages plants to root deeply and boosts their resilience to heat and drought.

This dry river separates the garden’s large foliage and wood fence from the home.

Sink Water, Reduce Risk

While Angelenos can fight fire without water, it certainly helps to have H20 on hand. Rain barrels and cisterns can ensure that is the case. Still, we consider water sinking features to be better “extra mile” resources for defensible space. Here’s why:

  • Ongoing Hydration. While all plants can ignite, well-hydrated, healthy foliage takes longer to dry and resists ignition.
  • Safe Space. When comprised of ember resistant materials, water sinking features offer fire fighters a place to stand as they work.
  • Soil Stabilization. Deep rooted foliage helps stabilize soil and slopes, even if the above ground foliage is lost to fire. These features inspire roots to seek deep water.

The best part of this protection? You don’t need to be there to provide it.

Store Water with Rain Barrels and Cisterns
Apply It When It’s Most Needed

Sink Water, Save Time

Saving water in rain barrels and cisterns means you have water to apply when it is needed. Incredibly helpful! Still, someone needs to apply it. Features that sink water work to keep your garden looking great without you lifting a finger – or a hose.

The City of Sierra Madre’s three demonstration garden bioswales have helped refuel its water independence.

IdealMow Bioswale Sinks Stormwater | Chris Cimino
A rock bioswale at city hall sinks rain and roof runoff.

Sink Water, Earn Money

Now you know why it makes sense – and more than cents – to sink water. Water districts, municipalities, the state, have even more reasons to entice Angelenos to take the plunge. When we sink water, we help fuel LA’s water independence, extend the life of stormwater infrastructure, and reduce risk of water-related damage.

The Municipal Water District Cash for Grass Program divides bioswales into three eligible “sustainable features:” rock gardens, dry rivers, and vegetated swales. For Angelenos feeling flashbacks of 2010 gravelscapes, you are not alone. I feel you! This is different. While the names are similar, these features have the opposite impact. Even the “rock” and “dry” features, help solve rainy day problems as they direct, sink and absorb stormwater. LADWP and LA County Public Works offer similar incentives.

Water sinking features can now earn tax credits too. The Safe Clean Water Program taxes the hardened areas of our properties that create runoff into public stormwater systems. Those that actively sink water can earn and trade credits.

Kirk Aoyagi at the Forbes Mountain Retreat | Rainy 2024 Native Plant Garden Tour

Sink Water, Elevate Peace of Mind

As we go from 100 degree red-flag days to deluge within a week, our emotions and landscaping strategies don’t need to whiplash with the weather. Whether the concern of the moment is fire, flood, slide, extreme heat, or drought, full climate cycle landscaping strategies can create an upward spiral of resilience. We’d like your peace of mind to elevate along with it!

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