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As there are forests in the vicinity of Palos Verdes, it is essential to study the risk of potential forest fires and take necessary measures to reduce the likelihood of fire damage.

To understand this risk, it is crucial to consider several factors. Firstly, it is important to examine the historical distribution of fires in the region, the preventive measures and surveillance provided by the community, and the climatic conditions that can increase the risk.

This type of risk is only significant for properties located near wooded areas. If the dwelling is not situated close to areas prone to rapidly spreading fires, such as forests, there is no need to conduct studies of this nature.

Ref: Fire Weather Indices WIKI

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The area where Palos Verdes is located consists of vast forests, and a significant part of these forests is part of the Alerce Costero National Park. This means that there is always a possibility of forest fires that could pose a threat to the project's buildings.

To assess the likelihood of a forest fire and determine preventive measures that can be taken, it is useful to analyze past fires in the area. In this area, fire events have primarily occurred around Corral, although there have also been a few incidents in the vicinity of Chaihuín:

Forest fires that occurred between 2013 and 2018 [1]

Based on this information, CONAF (the National Forestry Corporation) has created the following forest fire risk map:

Areas classified by CONAF according to the risk of forest fires [2].

In this map, Palos Verdes is not considered a high-risk area for forest fires.

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CONAF and the municipality of Corral have developed a comprehensive program for preventing forest fires.

On one hand, they have identified areas with 'vegetative fuel' that need to be periodically cleared. For this purpose, the following areas have been identified:

Vegetative Fuel Removal Works for Forest Fire Risk Mitigation in the Commune of Corral, Los Rios Region, Chile [1]

and Palos Verdes is included in this zone.

Additionally, CONAF has a monitoring program with predefined patrol routes shown here:

Preventive Forest Fire Patrol Routes in the Commune of Corral, Los Rios Region, Chile [1].

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The main concern for Palos Verdes, even though no events have occurred to date, is that there are seasons when south winds can potentially drive a forest fire northward:

The south-to-north winds could drive a forest fire towards Palos Verdes.

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The level of fire risk in Palos Verdes can be assessed using climatic data that includes information on humidity, temperature, and wind, collected hourly over several years. This data allows us to calculate the likely soil moisture index and the level of combustible material. Subsequently, we can determine the Forest Fire Danger Index Mark 5, denoted as $FFDI$, which is classified as follows:

In the case of Palos Verdes, the calculation (explained in the climatic data analysis) yields the following curve of monthly averages:

In summary, it can be concluded that the fire risk is generally low, as even during exceptionally high-risk summers, it does not exceed the threshold of 5, which corresponds to a low-risk level.

Furthermore, this low-risk level has remained consistently stable over the years.

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A Forest Fire Danger Index Mark 5 below 5 denotes a low risk, while values around 50 indicate a high risk. We will now describe the main cause. Under the climate/characterization section, you can find models of fire ignition and propagation that explain how these conclusions are reached.

If we observe the 'Drought Factor,' we see values around 6, with more extreme values around 10. This indicates that, especially during the summer, dry conditions often favor wildfires:

This leads to a slight water deficit, as shown by the Keetch-Byram Drought Index (KBDI), which reflects the moisture deficit in the topsoil, extending to the first few centimeters.

In extreme cases, values as low as 0.2 may be observed, indicating that the top 0.2 meters or 20 cm lack water, including the plant roots. The more than 3 cm (plus or minus 2 cm) observed in this case does affect vegetation and can facilitate fire propagation. This aligns with the 'Fuel Availability Factor' curve, which shows an increase in summer to values around 0.9, with the most extreme case being around 2.

However, this material is not conducive to fire propagation due to its high moisture content, as indicated by the 'Equilibrium Moisture Content (EMC)' curve:

Typically, when values are high, it hovers around 25%.

In other words, the risk is low despite the presence of combustible material because it has a high moisture content. Consequently, it is even more important to remove materials that can dry, such as grasslands, to prevent exceptional situations, as they would represent an exception to the existing favorable conditions.

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Regarding the risk of forest fires, the following conclusions can be drawn:

Although there have been no forest fires in the vicinity to date, it is always possible that they may occur in the future.

However, for Palos Verdes:

A fire could potentially start due to the south-north winds carrying flammable material.

Therefore, it is crucial to:

Ensure that the municipality and/or CONAF continue removing the vegetative fuel in the area along the highway.

Keep the grasslands around Palos Verdes short, especially before they dry out, given the difficulty of cutting them when they are dry.

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