10 Essential Rain Season Preparations for Bali, Lombok & Sumbawa

The rain season in Bali, Lombok, and Sumbawa can bring more than cooler temperatures and greener landscapes. For business owners, property investors, villa operators, restaurants, hotels, and other businesses, heavy rainfall can create operational challenges that should be addressed before they become costly problems.

From blocked drainage and roof leaks to flooding, slippery surfaces, power interruptions, and transportation disruptions, the rain season requires proper preparation.

As of September 2026, businesses should also avoid assuming that the rain season begins at exactly the same time across every part of Bali and Nusa Tenggara. BMKG's latest climate analysis shows that rainfall patterns vary by region and period, with Bali and NTB still experiencing relatively low rainfall probabilities in September 2026, while conditions are expected to become wetter toward the end of the year.

For businesses operating across Bali, Lombok, and Sumbawa, preparation should therefore begin before significant rainfall arrives.

Here are 10 essential preparations to consider.

1. Inspect Roofs and Building Structures

Before the rain season becomes more intense, inspect roofs, gutters, ceilings, walls, windows, and external structures.

Small cracks or damaged roofing materials can become serious sources of water intrusion during heavy rain. Check for:

• Broken or loose roof tiles
• Damaged waterproofing
• Blocked gutters
• Ceiling stains
• Wall cracks
• Leaking windows
• Damaged drainage pipes

For villas, hotels, restaurants, offices, and commercial buildings, preventive maintenance can be significantly less expensive than repairing major water damage after prolonged rainfall.

2. Clean and Improve Drainage Systems

One of the most important rain season preparations is ensuring that water can flow away from your property efficiently.

Inspect drains, gutters, channels, culverts, and other water-flow areas. Remove leaves, mud, plastic, and other debris that could create blockages.

Properties located on slopes or near rivers should receive additional attention because heavy rainfall can increase runoff and erosion risks.

Businesses should also understand the surrounding drainage conditions rather than focusing only on the drainage system inside their own property.

3. Check Flood and Water-Ingress Risks

Not every property faces the same rain season risks.

A coastal villa, hillside restaurant, urban office, and rural accommodation may experience very different problems.

Before the rain season, identify:

• Low-lying areas
• Previous flood points
• Areas where water accumulates
• Nearby rivers or waterways
• Steep slopes
• Retaining walls
• Basement or underground areas
• Critical electrical equipment located near the ground

Understanding these risks allows business owners to create practical prevention measures before an emergency occurs.

4. Protect Electrical Systems

Water and electricity create serious safety risks during the rain season.

Businesses should inspect electrical panels, outdoor electrical equipment, extension cables, lighting systems, pumps, generators, and other electrical installations.

Outdoor equipment should be properly protected from water exposure, while damaged cables or unsafe connections should be repaired by qualified professionals.

For hospitality businesses, particular attention should be given to pool areas, gardens, outdoor restaurants, parking areas, and other locations where guests or employees may encounter wet surfaces and electrical equipment.

5. Prepare for Slippery Surfaces and Workplace Accidents

The rain season can increase workplace safety risks.

Wet floors, moss-covered paths, slippery stairs, poor lighting, and standing water can increase the likelihood of accidents involving employees and guests.

Businesses should consider:

• Non-slip flooring
• Warning signs
• Adequate lighting
• Regular cleaning
• Handrails
• Covered walkways
• Appropriate footwear
• Clear emergency procedures

Workplace safety should be part of an overall K3 management system. Indonesia's current K3 framework includes Permenaker No. 13 of 2025 concerning the Occupational Safety and Health Advisory Committee (P2K3), which has been in force since November 19, 2025.

6. Review Employee and Guest Emergency Procedures

A good rain season plan should not only focus on buildings. People are equally important.

Businesses should make sure employees understand what to do during:

• Heavy rainfall
• Local flooding
• Electrical problems
• Road closures
• Property emergencies
• Evacuations
• Other weather-related disruptions

Hotels and villas should also ensure that guests know whom to contact if severe weather affects their accommodation.

Having clear emergency contacts and procedures can reduce confusion when conditions suddenly deteriorate.

7. Protect Business Equipment and Important Documents

Water damage can affect more than furniture and buildings.

During the rain season, important documents, computers, accounting records, equipment, inventory, and other valuable assets should be protected from potential water exposure.

Businesses should consider:

• Cloud backups
• Off-site document storage
• Elevated storage
• Waterproof containers
• Backup electricity
• Protection for IT equipment

Digital backups are particularly important because physical documents may be difficult or impossible to recover after serious water damage.

8. Review Property Compliance and Building Documentation

The rain season is also a useful reminder to review whether your property is properly documented and maintained.

Businesses operating buildings should ensure that relevant building approvals and certificates are properly maintained. Under the current risk-based business licensing framework, PP No. 28 of 2025 provides that businesses requiring building construction as business facilities are subject to requirements relating to Persetujuan Bangunan Gedung (PBG) and Sertifikat Laik Fungsi (SLF).

This is particularly relevant when businesses plan renovations, structural modifications, extensions, or other construction work.

PP No. 28 of 2025 has been in force since June 5, 2025 and replaced PP No. 5 of 2021 as the principal regulation for risk-based business licensing.

9. Prepare Your Business Continuity Plan

The rain season can affect business operations even when your own property is not flooded.

Heavy rainfall may disrupt:

• Employee transportation
• Guest arrivals
• Deliveries
• Construction schedules
• Outdoor events
• Supply chains
• Tourism activities
• Road access

Businesses should therefore have contingency plans for essential operations.

For example, hospitality businesses can prepare alternative indoor activities, flexible staffing arrangements, emergency suppliers, and communication procedures for guests.

Businesses should also monitor official weather and disaster information rather than relying exclusively on social media or informal forecasts.

10. Monitor Weather and Local Conditions

Finally, one of the simplest but most important rain season preparations is monitoring reliable information.

BMKG provides official weather and climate information that businesses can use to monitor rainfall conditions and weather developments. Current 2026 BMKG analyses show that rainfall patterns across Bali and NTB vary considerably by period and location, reinforcing the importance of checking updated local forecasts rather than assuming that every area will experience identical conditions.

Businesses in Bali, Lombok, and Sumbawa should also pay attention to local government and disaster-management announcements when heavy rainfall or flooding is expected.

Why Rain Season Preparation Matters for Businesses

Preparing for the rain season is not simply about fixing a leaking roof.

It is about protecting people, property, business assets, and business continuity.

For investors and business owners in Bali, Lombok, and Sumbawa, preventive maintenance can help reduce unexpected costs while improving operational resilience.

The rain season can also reveal weaknesses that may otherwise remain unnoticed during dry months. Poor drainage, inadequate waterproofing, unsafe electrical installations, and insufficient emergency procedures can become much more serious once rainfall increases.

A proactive approach allows businesses to identify these weaknesses early and address them before they affect customers, employees, or daily operations.

Rain Season Preparation Checklist

Before the rain season intensifies, businesses should ask:

• Is the roof properly maintained?
• Are all drainage systems clear?
• Does the property have flood-prone areas?
• Are electrical systems protected from water?
• Are walkways and stairs safe when wet?
• Are emergency procedures documented?
• Are important documents and data backed up?
• Are employees aware of emergency procedures?
• Are business-critical assets protected?
• Are building and business compliance documents up to date?

If the answer to any of these questions is no, it may be time to take action.

For businesses operating in Bali, Lombok, and Sumbawa, preparing early can make the rain season much easier to manage.