San Diego may be known for its sunshine, but when heavy winter storms arrive, even a short period of intense rainfall can cause serious property damage. Flooded garages, leaking roofs, overflowing drains, and water intrusion can affect homes, businesses, and multi-unit properties—sometimes long after the rain has stopped.

With a strong El Niño developing for the 2026–2027 winter season, preparation is especially important. According to the National Oceanic and Atmospheric Administration (NOAA), El Niño is expected to influence winter weather patterns, increasing the likelihood of wetter-than-average conditions across portions of the southern United States, including California.

While El Niño doesn’t guarantee flooding in every neighborhood, it does provide an important reminder: the best time to address potential water damage risks is before the next storm arrives.

Understanding where your property may be vulnerable, taking preventive measures, and having an emergency response plan can help reduce damage and make recovery easier.

What Does El Niño Mean for San Diego Properties?

El Niño is a naturally occurring climate pattern characterized by warmer-than-average ocean temperatures in the central and eastern tropical Pacific. These changes can influence atmospheric circulation and seasonal weather patterns, sometimes bringing more frequent or intense winter storms to Southern California.

In San Diego, prolonged or heavy rainfall can overwhelm drainage systems, saturate soil, and expose vulnerabilities in buildings that may go unnoticed during dry weather.

Common storm-related property risks include:

• Roof leaks: Damaged roofing materials, deteriorated flashing, and clogged roof drains can allow water into ceilings and walls.
• Poor drainage: Blocked gutters, downspouts, and storm drains can cause water to accumulate near foundations and entrances.
• Window and door leaks: Worn weatherstripping and deteriorated sealants can allow wind-driven rain into interior spaces.
• Ground-level flooding: Garages, basements, storage areas, and low-lying commercial spaces may be vulnerable to accumulating runoff.
• Hidden moisture and mold: Water trapped beneath flooring, behind drywall, or inside building materials can lead to additional damage if not properly addressed.

Recognizing these risks before heavy rainfall begins can help homeowners, business owners, and property managers take action while conditions are still safe.

How to Prepare Your Property Before El Niño Storms

Taking a few preventive steps now can reduce the likelihood of water intrusion and help identify problems before they become costly restoration projects.

1. Inspect Your Roof and Exterior

Roofs are among the most important areas to evaluate before winter storms. Look for visible signs of missing or damaged roofing materials, deteriorated flashing, or areas where water may collect.

Examine accessible areas around windows, doors, and exterior walls for cracks, damaged sealants, or other openings that could allow rainwater inside.

Any potentially unsafe or elevated inspection should be performed by a qualified professional. Addressing suspected leaks before a storm is generally easier than repairing extensive water damage afterward.

2. Clear Gutters, Downspouts, and Drainage Areas

Leaves, dirt, and debris can obstruct the flow of rainwater. When gutters or drains become clogged, water may overflow and accumulate against a building rather than moving safely away.

Before heavy rain:

• Remove debris from accessible gutters and downspouts.
• Check private storm drains and drainage channels for blockages.
• Make sure runoff is directed away from vulnerable entrances and foundations.
• Report blocked public storm drains to the appropriate local authority.

The City of San Diego encourages residents and businesses to prepare drainage areas before storms and report potential stormwater problems through its Get It Done system.

3. Protect Areas Prone to Flooding

If your property has experienced flooding or recurring water intrusion, consider additional protective measures before the rainy season.

Sandbags can help redirect shallow surface runoff away from vulnerable openings, including garage doors and low-lying entrances. The City of San Diego provides limited free sandbags at designated recreation centers while supplies last, although residents and businesses must supply the sand.

Move important documents, electronics, inventory, and other valuable items away from floors in areas susceptible to water accumulation.

Remember that sandbags provide limited protection and cannot make a building floodproof or reliably stop rising floodwater.

4. Review Your Emergency Contacts and Insurance Coverage

Preparation isn’t limited to the physical condition of a property. Knowing whom to call when water damage occurs can make the initial response more organized.

Keep emergency contacts readily available, including utility providers, maintenance professionals, your insurance representative, and a qualified restoration company.

Review your insurance policy before the rainy season to understand your coverage and documentation requirements. Standard property insurance policies may exclude certain types of flood damage, making it important to understand your specific protections before a loss occurs.

A Special Consideration for San Diego Property Managers

For property managers, storm preparation involves more than protecting an individual building. Water damage can affect multiple units, disrupt tenants and businesses, and require coordination among property owners, association boards, maintenance teams, insurance representatives, and restoration professionals.

A leak originating on an upper floor, for example, may travel through walls and ceilings before becoming visible in neighboring units. The longer the damage goes unaddressed, the more complicated the response can become.

Having a clear emergency plan can help property managers respond efficiently and communicate consistently when an incident occurs.

Free Resource: Emergency Response Checklist for San Diego Property Managers

Generation Contracting has developed an Emergency Response Checklist for San Diego Property Managers to help property teams organize their response to unexpected property emergencies.

The practical checklist covers three essential stages:

Immediate Safety and Stabilization: Assessing potential hazards, restricting unsafe areas, identifying the source of damage, notifying appropriate contacts, and arranging professional assistance.

Documentation, Communication, and Coordination: Recording damage, tracking response activities, communicating with residents or tenants, and coordinating access for restoration professionals.

Follow-Up, Recovery, and Preparedness: Monitoring restoration progress, maintaining communication, and identifying improvements to emergency procedures.

Although particularly useful during storm-related water damage incidents, the checklist also addresses fire, mold, sewage, and other property emergencies. Reviewing this resource before an emergency can help property management teams identify gaps in their existing procedures and better prepare for unexpected situations.

What to Do If Water Damage Occurs During a Storm

Even with preventive measures, significant rainfall can overwhelm drainage systems or expose existing building vulnerabilities.

If water enters your home or commercial property, taking prompt, appropriate action can help limit additional damage.

Prioritize Safety

Avoid entering flooded areas where electrical hazards, sewage, structural damage, or other dangerous conditions may be present. Never walk or drive through floodwater, and follow instructions from local emergency authorities.

If the property is unsafe, evacuate and contact emergency services as appropriate.

Identify and Limit the Water Source

If it is safe to do so, identify where water is entering the building. A broken pipe may require shutting off the water supply, while stormwater intrusion may require keeping people and belongings away from affected areas until conditions improve.

Do not attempt electrical repairs or enter hazardous areas to stop water intrusion.

Document the Damage

Once conditions are safe, photograph or video affected rooms, walls, flooring, furnishings, equipment, and other damaged materials.

Maintain a record of when the damage was discovered, what areas were affected, and any immediate actions taken. This information can be valuable when communicating with restoration professionals and insurance representatives.

Contact a Professional Water Damage Restoration Company

Standing water may be the most visible sign of damage, but it isn’t necessarily the only concern.

Moisture can penetrate drywall, insulation, subflooring, carpeting, and other porous materials. Even when a surface appears dry, trapped moisture may remain within the structure.

Professional restoration teams use specialized equipment and moisture monitoring techniques to assess affected areas, extract water, and establish appropriate drying procedures.

Prompt attention is particularly important because prolonged moisture exposure can contribute to mold growth, deteriorating materials, and additional restoration needs.

How Generation Contracting Helps San Diego Recover from Water Damage

For more than 30 years, Generation Contracting & Emergency Services has helped San Diego County property owners respond to property damage emergencies.

Whether a storm causes water intrusion into a single-family home, a commercial facility, or a multi-unit property, Generation provides comprehensive services to address damage and support the recovery process.

Services include:

• 24/7 Rapid Emergency Response: Prompt assessment of water damage and development of an appropriate restoration plan.
• Water Extraction and Sewage Cleanup: Removal of standing water and specialized cleanup when sewage or contaminated water is involved.
• Advanced Structural Drying: Professional drying equipment and moisture monitoring to address water within affected materials.
• Mold Prevention and Remediation: Moisture mitigation and professional remediation when mold contamination is present.
• Structural Repairs and Restoration: Repair and reconstruction of damaged flooring, drywall, and other building components.
• Insurance Coordination: Documentation and communication to help property owners navigate the restoration and claims process.

From initial emergency response through repairs and restoration, Generation Contracting works to help property owners return their buildings to safe, functional conditions.

Prepare Now. Know Who to Call When the Storm Arrives.

El Niño may bring increased rainfall to San Diego this winter, but preparation shouldn’t wait until severe weather is in the forecast.

Inspecting vulnerable areas, keeping drainage systems clear, protecting flood-prone spaces, and establishing an emergency response plan are practical steps that can help reduce the impact of storm-related water damage.

For property managers, having a structured response process is especially valuable when multiple residents, tenants, and buildings may be affected. And if heavy rain causes water damage to your home or business, Generation Contracting & Emergency Services is available 24 hours a day, seven days a week.

Call (858) 679-9928 for 24/7 emergency water damage restoration services throughout San Diego County.