We're hoping that storms this winter will replenish the much-needed mountain snow pack and fill our depleted reservoirs to the brim. But if El Niño predictions hold true, it could be too much of a good thing.
Torrential downpours hitting drought-stricken California soil is a recipe for mudslides and flooding. As we brace ourselves for the predicted onslaught of rain, get ahead of the game by tackling as many to-dos from our list as you can to help protect your home and garden.
1. Clean roofs, gutters, and downspouts
Rake fallen leaves from roofs and clear debris from gutters and rain downspouts, checking for and repairing any cracks. After the first rainfall, clean out gutters again as leaves brought down by the rain can easily re-clog drainage systems.
2. Fix leaks
Perhaps you've gotten by the last three comparably dry winters with a leaky roof, but now's the time to repair any cracks or other damage in roofs and windows.
3. Assess garden drainage
Make sure that soil slopes away from your home or any other structures and that water drains easily from patios and decks. In the garden above designed by In Harmony Sustainable Landscapes (inharmony.com), a hidden pipe runs under the swath of river stones and channels run off from the roof downspout into a planted infiltration basin 10 feet from the house.
4. Turn off irrigation
It sounds like a no-brainer, but be sure to switch off outdoor watering systems as soon as the rains hit. If needed, selectively turn on drip systems for containers or raised beds that may dry out more quickly.
5. Create a bioswale or rain garden
Divert excess rainwater from your downspout to a 1-foot-deep basin at least 10 feet from your house. Make the swale 10% to 20% as big as the roof and other surfaces that drain into the garden. The swale can be planted as a rain garden or filled with sand and stones as a dry creek bed. Either way, the low area will help keep water on site instead of washing away to a storm drain. To address a drainage issue in a client's yard (pictured above) and keep water on site, landscape designer Isabelle Duvivier (idarchitect.com) created a bioswale 10 feet away from the home to channel rainwater.
6. Lay mulch on pathways
Cover dirt pathways with a thick layer of bark or straw mulch to prevent mud from tracking in the house and encourage water to sink into the ground rather than quickly running off.
7. Assess trees and large shrubs
Many mature trees and large shrubs have suffered with the drought. Bring in a certified arborist to assess tree health and identify any weak limbs or diseased plants that may become hazards in winter storms.
8. Keep surfaces permeable
When rain falls on impervious surfaces such as poured concrete driveways, stone patios, and mortared pavers, it quickly runs off the area, off the property, and often straight into a city storm drain. The more we can keep rainfall on site—soaking into the soil and replenishing the underground water table—the better. Choose permeable surfaces such as crushed gravel and flagstone with gaps between pavers for new gardens (check out these 13 stylish options for hardscaping). In the urban garden pictured above, landscape designer Beth Mullins (growsgreen.com) left spaces between poured concrete pads and mulched landscape beds to keep rainwater on site.
9. Save rainwater
California will be in a state of drought even after a wet winter and ecologists are encouraging us to consider dryness the new normal. Hold the gallons of water that run off your roof this winter in a rain barrel, such as the one pictured above, that can be used to water the garden in spring and summer. Add an attractive rain chain to connect from the gutter to a rain barrel or other catchment and it can double as art in the garden. Pictured below, a copper rain chain made of upturned cups channels water to an underground pipe and infiltration basin for use in the garden. (Design: In Harmony Sustainable Landscapes, inharmony.com.)
10. Add berms
Form shallow mounds of earth to help channel rain water away from your house to areas that are fit to absorb the excess water (such as rain gardens, swales, or areas with fast-draining, sandy soil). On hillsides, form the mounds with the help of ropes of straw wattle, installed to run horizontally along the slope to channel water and help prevent erosion.
11. Stock up on sandbags
Have a stack of sandbags on hand to prevent water running into low areas such as crawl spaces beneath the house in the event of a downpour.
12. Amend soil
Heavy clay or compacted soil will not absorb water well. To prepare the soil to receive rainfall, add a generous heap of compost (4 to 6 inches spread on top of garden beds), break up any compacted colds, and turn over the soil with a shovel.
13. Make your own disaster supply kit
Pack essentials into a water-proof plastic bin so that you have everything you need in the event of a flood or power outage. We've outlined a few of the essentials here. Cross check what you need with our 'How to put together an earthquake kit' video.
14. Double check your insurance policy
Flood insurance is not always included in standard homeowner policies. If your home is in an at-risk area, consider bumping up your coverage at least 30 days before expected storms. FEMA offers coverage for flooding through the National Flood Insurance Program (NFIP). For more information, visit FEMA's flooding information site.
15. Take advantage of moist soils for planting
The silver lining of a wet winter is that it can be a good time to plant out large trees and shrubs. The cool temperatures and moist soils give them a head start for growth next spring. Native wildflowers also thrive in damp soils. Sprinkle seeds in a cleared area for a meadow garden this spring. If soil is soggy, hold off planting California native trees and shrubs, Australian natives, and many South African native plants that cannot tolerate damp soil conditions. Wait to plant any sloped areas that may be at risk for mudslides.
For more information on what you can do to prepare, please visit: www.floodprepareCA.com (California Department of Water Resources), http://resilience.abag.ca.gov/floods/ (Association of Bay Area Governments Resilience Program "Flooding Maps and Information"), www.ladbs.org (Los Angeles Department of Building and Safety "Homeowners Guide for Flood, Debris Flow and Erosion Control"), www.ready.gov (National Weather Service) and www.aaa.com (AAA Auto Insurance).