The Board of Directors of the National Commission for Risk Prevention and Emergency Response undertakes the study of the reports prepared by Messrs. Eduardo Malavassi Vargas representing OVSICORI, Sergio Paniagua Pérez of the Red Sismológica Nacional, Guillermo Alvarado Induni of the Observatorio Sismológico y Vulcanológico del Arenal y Miravalles and the Instituto Costarricense de Electricidad, and Lidier Esquivel Valverde of the CNE, which deal with the restrictions for land use in the surroundings of the Arenal Volcano, accompanied by maps with the respective detail as well as restrictions for the visit and free transit of persons.
The Chairman informs the Directors that on the occasion of the events that have occurred in the sector of the Arenal Volcano, which sadly caused the death of two persons and material losses, and in the exercise of the powers assigned to the National Commission for Risk Prevention and Emergency Response by the Ley Nacional de Emergencia, No. 7914 of September 28, 1999, a joint action of the Commission with those volcanological research bodies was sought in order to achieve technical-scientific studies that allow carrying out actions aimed at safeguarding the life and property of the inhabitants of the area, entrepreneurs, and tourists.
These reports are duly supported by information of the highest level in the technical-scientific area, at the national level, and are also based on research and assessments of the prehistoric and historical behavior of the Arenal Volcano, which have demonstrated that this is an area with very high volcanic risk potential, which obliges the intervention of the National Commission for Risk Prevention and Emergency Response, in accordance with the powers that the Ley Nacional de Emergencia grants it in matters of risk prevention.
In accordance with what was stated by the Chairman of the Board of Directors and in view of the technical reports, the Board of Directors of the National Commission for Risk Prevention and Emergency Response,
1°—The massif of the Arenal Volcano and its constant eruptive manifestations have become one of the greatest tourist attractions of the country, both for the spectacle offered by the volcano and its activity, and for the abundant hot springs that exist in the surroundings.
2°—The construction of infrastructure (mainly cabins, hotels, spas, and restaurants) has an extremely high growth rate, and part of it has been developed in areas over which an imminent volcanic threat hangs. This has been due in part to the scarce oversight by the institutions, within whose competencies lies the control of projects, through the issuance of permits for the extraction of materials, construction of works, and operation of facilities.
3°—This situation may worsen because a significant number of projects, currently in the proposal stage or beginning the construction phase, show a worrying tendency to be located near sites that have historically remained unoccupied, due to being highly exposed to the activity of the Arenal Volcano.
4°—As a result of the research, observation, and continuous monitoring, carried out with the participation of the Observatorio Vulcanológico y Sismológico de Costa Rica (OVSICORI-UNA), the Red Sismológica Nacional (RSN-UCR/ICE), the Observatorio Vulcanológico y Sismológico de Arenal y Miravalles (OSIVAM-ICE), and the National Commission for Risk Prevention and Emergency Response (CNE), it was possible to determine that:
. The limited knowledge currently available about this type of process does not yet allow for the installation of an efficient early warning system to evacuate vulnerable sites with sufficient advance notice and thus avoid regrettable accidents; . It is possible to identify, with considerable certainty, areas that in the short term may be affected by one or another phenomenon, a product of this continuous volcanic activity.
5°—It is necessary to regulate land use in the zone of influence of the Arenal Volcano for any activity intended to be carried out there, whether productive or service-oriented, public or private, in order to control the increasing levels of risk present in this region, and in the interest of improving the distribution of such activities in the future, in accordance with the threat level that must definitively be respected.
6°—The country's volcanic research, observation, and monitoring centers, considering factors related to the historical eruptive activity of the Arenal, as well as morphological aspects that may determine the direction and reach of any volcanic process, determined that 4.5 km is the maximum distance that lava flows or pyroclastic flows (flujo piroclástico) have been able to travel, produced by the lateral collapse of crater walls in the presence of lava fronts, and to which large or medium-sized fragments (pyroclasts, piroclástos) have reached. One kilometer must be added as a safety margin, due to the eventuality that in the future such displacements may reach beyond what is foreseen, and to protect the site from eventual collateral effects such as forest fires or gas flows at high temperatures.
7°—This same criterion must be applied to those watercourses that have their headwaters in the upper part of the volcanic massif, given the possibility that their valleys may serve to channel volcanic phenomena, as has occurred in contemporary events in this sector.
8°—Within the area comprised in the circle of a 5.5 km radius centered on the crater of the Volcano, there is a zone characterized by its extremely high level of exposure to the volcanic threat, adverse topographic conditions, legal limitations (such as territories of the Arenal Conservation Area), and primary forests that deserve to be considered absolute reserve areas (no-construction and restriction of human activity).
9°—This zone covers approximately two-thirds of the northwest and southwest quadrants of said circle, and one-quarter of the northeast and southeast quadrants (total 40 km²); in it are found the channels of the main streams that have their headwaters in the Volcano; all the flanks of the cone from its base, and the entire western flank of the volcanic edifice, including the eastern limit of Lake Arenal. Likewise, the specialized entities cited above consider it possible that in the future, the evolution of volcanic activity may take advantage of flanks that to date have not been permanently or directly affected.
10.—Development poles should not be encouraged in areas that have previously been determined to be high risk.
11.—There exists a condition of volcanic threat to the life and property of persons who inhabit permanently or temporarily or transit through the zone within a radius of less than 5.5 kilometers measured horizontally from the upper crater of the Arenal Volcano, which generates a situation of high imminent risk of emergency (95 km²), duly distinguished on the maps, with the possibility of use provided it has a study endorsed by the volcanic monitoring centers.
12.—Within the area indicated in the previous point, there is a zone of extremely high risk (altísimo riesgo) due to the level of exposure to the volcanic threat, whose extension is approximately 40 km², duly marked on the map.
13.—In compliance with Agreement No. 465-00 of the Ordinary Session of the Board of Directors of the National Commission for Risk Prevention and Emergency Response, held on October 25, 2000, the specialists who prepared the technical studies proceeded to detail more broadly a series of concepts, as well as proceeded to delimit the different zones subject to restrictions and to prepare the respective maps.
14.—Said Technical Advisory Committee on Volcanology proceeded to prepare the "Document Annex: Restrictions for land use in the surroundings of the Arenal Volcano," which is transcribed verbatim below:
"Document Annex: Restrictions for land use in the surroundings of the Arenal Volcano:
It is necessary to make the following expansion, which also aims to facilitate the understanding of both public and private officials, as well as the institutions that will have to use said regulation, of the level of restrictions that must be implemented.
The area indicated as "no-construction and restriction of human activity (absolute reserve)" in the aforementioned document must be subjected to the following specific uses and restrictions:
1.—Restrictions for land use.
1.1 General restrictions for the entire zone (R) or red zone (zona roja) a) Prohibit the construction of new tourist activities (lodging, restaurants, spas, trails, camps, canopy tours, mountaineering (andinismo), hiking (senderismo), horseback riding (cabalgatas), road construction, complementary facilities for providing tourist services such as warehouses, shelters (escampaderos), etc.) or expansions of existing ones. This recommendation applies to the entire area marked as absolute restriction (red zone (zona roja)), except for those sectors indicating otherwise (case of zones R2 and R3).
- b)The establishment of new dwellings within existing farms or in segregations thereof is prohibited; it applies to the entire area marked as absolute restriction (red zone (zona roja)).
1.2 Particular uses and restrictions (Figure 1) a) Restriction Zone 1 (R1):
The corresponding authorities must take drastic measures so that, in the shortest possible time, activities involving concentrations of people are not permitted. This is because said areas have historical and prehistoric antecedents of glowing clouds (nubes ardientes), and due to their current use, they are in conflict with the level of risk derived from the occurrence of the aforementioned phenomena.
Those agricultural activities (actividades agropecuarias) already established in this sector shall be governed by what Restriction Zone establishes.
- b)Restriction Zone 2 (R2):
This sector may be used by the Arenal Conservation Area (ACA), in accordance with what is established in section 2.2, subsections a and b, in the chapter on Restrictions on Visits and Transit of Persons.
For this, it must have a duly approved Emergency Plan, trail demarcation, emergency exits, information on the threats to visitors, in several languages (Spanish and English at least). In this sector, new infrastructure or services for tourists shall not be built, unless they are trails, signage, or other open-air facilities.
The use of materials by the ACA to cover its own needs is possible, provided they comply with the regulations in force in that field.
- c)Restriction Zone 3 (R3):
To the west of the Carretera al Castillo (between the road and the edge of Lake Arenal and the Río Arenal), only the establishment of trails for hiking (senderismo) or horseback riding (cabalgatas) shall be permitted, as well as fishing in the lake, in accordance with existing regulations on the matter, or other open-air activities, provided they do not involve the generation of constructions of any type, which must be located outside the delimited restriction area. The establishment of camping facilities or any activity requiring them shall also not be permitted.
Material extraction and agricultural activities (actividades agropecuarias) shall be governed according to what Restriction Zone R4 establishes and in accordance with the regulations in force.
- d)Restriction Zone 4 (R4):
Permitted activities are those of a forestry, agricultural (agropecuaria) nature, and the exploitation of construction materials (quarries, tajos), when they were established prior to the declaration of the Board of Directors of the CNE and do not involve a concentration of population exceeding seven (7) persons in sites of high vulnerability. The construction of new dairies, stables, or warehouses or the expansion of pre-existing ones shall not be permitted. Existing facilities for forestry, agricultural (agropecuarios) services, and material exploitation (provided they have the respective permits) may be repaired.
2.—Restrictions for the visit and transit of persons.
While the Arenal Volcano remains active with the emission of gases, lava flows, pyroclastic flows (flujos piroclásticos), ash, volcanic gases, the restricted area shall be divided into two subzones, regarding the visit of persons and transit (figure 2).
2.1 Subzone of absolute prohibition of visits and transit of persons: (Sub-1) Only access to this zone shall be permitted to persons who meet the following requirements:
a. Researchers in volcanology at the service of national public or private institutions or foreign scientists accompanied by personnel from national institutions, provided they carry identifications accrediting them as such.
b. Officials of emergency response institutions carrying out rescue or salvage operations or monitoring and follow-up, provided they carry identifications accrediting them as such.
c. Police authorities in the course of apprehending persons or judicial investigation, provided they carry the corresponding identifications.
2.2 Subzone of partial restriction of visits and free transit of persons: (Sub-2) Only visits to the lower portion of the western flank of the volcano and the lands located west of it, between the Arenal Conservation Area and Lake Arenal and the Río Arenal, shall be permitted, under the following conditions:
a. Controlled entry of small groups of persons (10) to the Arenal Conservation Area (ACA) shall be permitted, for a limited time and under the strict supervision of ACA officials, up to the sector delimited by the 600 m.a.s.l. elevation; this limit must be duly marked by the officials of this institution.
b. The ACA must have an alarm system to order evacuations, evacuation plans duly approved by the CNE, and ensure that persons do not spend the night or camp within it. The only tourist service that may be provided within this zone is that of a tour guide for groups of people, as well as transportation to and from the zone.
These guides must be duly certified by the Instituto Costarricense de Turismo (ICT).
c. The road that crosses the foot of the western flank of the volcano shall be free for circulation; however, it is recommended to establish controlled vehicular flow, as well as the installation of informative signs about the different restrictions that exist in the zone.
d. The lands located between the road and the Arenal Reservoir and the Río Arenal may be visited to carry out activities indicated for Restriction Zone 3, R3, of section 1.2, mentioned above.
Likewise, it must be clarified to both individuals and property owners, as well as to ACA officials with activities within the red zone (zona roja) or absolute restriction area, that this area has a high risk, so it must be adequately demarcated and signposted or, if applicable, fenced." 15.—The Ley Nacional de Emergencia provides in Article 26 that the National Commission for Risk Prevention and Emergency Response is obliged to issue resolutions based on threats or risks in any part of the national territory, which have binding character for the public institutions responsible for the corresponding sector.
16.—The Ley Nacional de Emergencia provides as an attribution of the Board of Directors of the National Commission for Risk Prevention and Emergency Response the fulfillment of the responsibilities assigned by the Law, and the Reglamento de Prevención de Riesgos y Atención de Emergencias, Decreto Ejecutivo No. 28445-MP, in its Article 44, states that the Board of Directors shall authorize binding resolutions.
- 1That in accordance with Articles 1, 2, and 3 of the Ley Nacional de Emergencia, it is the competence of the National Commission for Risk Prevention and Emergency Response to take the pertinent ordinary actions to prevent situations of imminent risk of emergencies, with the purpose of safeguarding human life, physical integrity, the patrimony of the country's inhabitants, and in general, the conservation of the legal and social order. As a guiding principle of the application of the assigned competencies, said Commission indicates that rationality and proportionality of measures must be applied when confronting the need intended to be addressed and the means deemed adequate for it.
2.—That among the ordinary duties of the National Commission for Risk Prevention and Emergency Response is the declaration of zones of the country that present situations of imminent risk of emergencies, as well as the definition of policies, actions, and programs, both sectoral and national, regional, or local, aimed at preventing situations of imminent risk of emergencies (Articles 4 subsection b), 16 subsection b), and 24 subsections e) and i).
- 3That the presentation of the results of the technical studies prepared jointly by OVSICORI-UNA, OSIVAM-ICE, RSN-ICE-UCR, and the CNE demonstrates the need to declare an imminent risk zone in the area of the surroundings of the Arenal Volcano, making official the maps prepared by the recently indicated technical team as descriptive of the zone. Therefore,
IT IS RESOLVED: First: To accept, in the terms indicated below, the Reports presented by the Technical Advisory Committee on Volcanology, composed of Messrs. Eduardo Malavassi, Sergio Paniagua, Guillermo Alvarado, and Lidier Esquivel. Said reports are those called "Restrictions for Land Use in the Surroundings of the Arenal Volcano" and "Document Annex: Restrictions for Land Use in the Surroundings of the Arenal Volcano"; as well as the Zoning Maps for "Restrictions for the Visit and Free Transit of Persons" and "Restrictions for Land Use—Restriction Zones," where the breakdown and detail of the imminent risk zones are recorded.
Second: The area located in the surroundings of the Arenal Volcano, as indicated in the Maps prepared by the Technical Advisory Committee on Volcanology, is hereby declared an imminent risk zone (zona de riesgo inminente).
Third: In order to have more elements to definitively resolve on the scope of the restrictions proposed in the reports cited in the First Resolve of this binding resolution, regarding the zone called Restriction Zone (R 1), the Government of the Republic shall be requested to arrange for the technical advice of foreign professionals, preferably Japanese and American nationals of the highest order. The foregoing is for the purpose of analyzing the risk situations for persons that could occur in the Restriction zone (R 1) and recommending the corresponding measures, whether prohibitive, restrictive, or preventive, with an indication of the technical characteristics of the prevention measures, if they are applicable. All this so that the National Commission for Risk Prevention and Emergency Response, when deciding on the restrictions on human activity, has the best elements of judgment for applying the criteria of proportionality and rationality.
Fourth: While the process under the Foreign Mission is underway, as a preventive measure, the Board of Directors of the National Commission for Risk Prevention and Emergency Response proceeds to issue to the Institutions detailed below the following instructions that are mandatory in the zone indicated in the described Maps:
a. To the Ministry of Public Works and Transport (Ministerio de Obras Públicas y Transportes): Instruct the Instituto Geográfico Nacional (IGN) to: i) calculate the coordinates of the circumference of the circle of a 5.5 km radius whose center of origin is the crater of the Arenal Volcano, as well as those of the limit of the extremely high risk zone (R1 zone on the Land Use Restrictions Map), with a perimeter close to 29 linear kilometers; ii) prepare the cartographic sheets showing these lines; iii) formulate the project for the respective demarcation (amojonamiento), including the budget; iv) in coordination with the Instituto Costarricense de Turismo, proceed with the preparation and placement of the signs detailed in point 1) of this Resolve.
b. To the Municipality of San Carlos: i) Within the zone called extremely high risk zone (R 1 zone on the Land Use Restrictions Map), suspend the granting of new operating or construction permits, including expansions of existing works, until the technical studies indicated in the Third Resolve of this resolution are carried out. In the rest of the 5.5 km, the permit may be granted if there is prior authorization from the National Commission for Risk Prevention and Emergency Response. ii) Apply the information included in the cartographic sheets prepared by the Instituto Geográfico Nacional (IGN), and respect and enforce respect for the demarcation (amojonamiento) referred to in point 1) of this Resolve.
c. To the Ministry of Health (Ministerio de Salud): Within the zone called extremely high risk zone (R 1 zone on the Land Use Restrictions Map), suspend the granting of new sanitary operating permits, until the technical studies indicated in the Third Resolve of this resolution are carried out. In the rest of the 5.5 km, the permit may be granted if there is prior authorization from the National Commission for Risk Prevention and Emergency Response.
d. To the Ministry of Environment and Energy (Ministerio del Ambiente y Energía): i) Within the zone called extremely high risk zone (R1 zone on the Land Use Restrictions Map), suspend the granting of new permits for the development of extractive activities, including expansions of existing ones, until the technical studies indicated in the Third Resolve of this resolution are carried out. In the rest of the 5.5 km, the permit may be granted if there is prior authorization from the National Commission for Risk Prevention and Emergency Response. ii) Determine the conditions under which the limits of the Arenal Conservation Area (ACA) could be expanded, so that it also serves as a containment instrument to prevent the improper use of the aforementioned zones.
e. To the Instituto Nacional de Vivienda y Urbanismo: Within the zone called extremely high risk zone (R1 zone on the Land Use Restrictions Map), suspend the granting of new permits for housing construction, including expansions of existing ones, until the technical studies indicated in the Third Resolve of this resolution are carried out. In the rest of the 5.5 km, the permit may be granted if there is prior authorization from the National Commission for Risk Prevention and Emergency Response.
f. To the Instituto Costarricense de Turismo: i) Establish standards for entrepreneurs in the tourism sector to formulate contingency plans, as well as for the demarcation of evacuation routes, and hire trained personnel to handle possible preventive evacuations and other similar actions. ii) Prepare accurate information to be provided to visitors, related to the volcanic threat, the level of risk, the limits that must be respected, and recommended measures in the event of a volcanic eruption. iii) Advise the Instituto Geográfico Nacional in the demarcation with signs in several languages (at least English/Spanish) about the maximum limits and the conditions for approaching the volcanic massif, while the demarcation (amojonamiento) recommended by the former is carried out, as ordered by this resolution.
g. To the Colegio Federado de Ingenieros y de Arquitectos: Disseminate this binding resolution among its members.
Fifth: Notify this Binding Resolution to all natural and legal persons located in the 5.5 km zone, whether residents, commercial establishments, tourist establishments, or agricultural establishments (establecimientos agropecuarios).
Sixth: Publish this Binding Resolution in the Official Gazette La Gaceta.
DOCUMENT ANNEX:
Restrictions for land use in the surroundings of the Arenal Volcano It is necessary to make the following expansion, which also aims to facilitate the understanding of both public and private officials, as well as the institutions that will have to use said regulation, of the level of restrictions that must be implemented.
The area indicated as "no-construction and restriction of human activity (absolute reserve)" in the mentioned document must be subjected to the following specific uses and restrictions:
1.—Restrictions for land use 1.1 General restrictions for the entire zone (R) or red zone (zona roja) a) Prohibit the construction of new tourist activities (lodging, restaurants, spas, trails, camps, canopy tours, mountaineering (andinismo), hiking (senderismo), horseback riding (cabalgatas), road construction, complementary facilities for providing tourist services such as warehouses, shelters (escampaderos), etc.) or expansions of existing ones. This recommendation applies to the entire area marked as absolute restriction (red zone (zona roja)), except for those sectors indicating otherwise (case of zones R2 and R3).
- b)The establishment of new dwellings within existing farms or in segregations thereof is prohibited; it applies to the entire area marked as absolute restriction (red zone (zona roja)).
1.2 Particular uses and restrictions (Figure 1) a) Restriction Zone I (R 1):
The corresponding authorities must take drastic measures so that, in the shortest possible time, activities involving concentrations of people are not permitted. This is because said areas have recent historical and prehistoric antecedents of having been affected by pyroclastic flows (flujos piroclásticos) or glowing clouds (nubes ardientes), and due to their current use, they are in conflict with the level of risk derived from the occurrence of the aforementioned phenomena.
Those agricultural activities (actividades agropecuarias) already established in this sector shall be governed by what Restriction Zone R4 establishes.
- b)Restriction Zone 2 (R2):
This sector may be used by the Arenal Conservation Area (ACA), in accordance with what is established in section 2.2, subsections a and b, in the chapter on Restrictions on Visits and Transit of Persons.
For this, it must have a duly approved Emergency Plan, trail demarcation, emergency exits, information on the threats to visitors, in several languages (Spanish and English at least). In this sector, new infrastructure or services for tourists shall not be built, unless they are trails, signage, or other open-air facilities.
The use of materials by the ACA to cover its own needs is possible, provided they comply with the regulations in force in that field.
- c)Restriction Zone 3 (R3):
To the west of the Carretera al Castillo (between the road and the edge of Lake Arenal and the Río Arenal), only the establishment of trails for hiking (senderismo) or horseback riding (cabalgatas) shall be permitted, as well as fishing in the lake, in accordance with existing regulations on the matter, or other open-air activities, provided they do not involve the generation of constructions of any type, which must be located outside the delimited restriction area. The establishment of camping facilities or any activity requiring them shall also not be permitted.
Material extraction and agricultural activities (actividades agropecuarias) shall be governed according to what Restriction Zone R4 establishes and in accordance with the regulations in force.
- d)Restriction Zone 4 (R4):
Permitted activities are those of a forestry, agricultural, and livestock nature, and the extraction of construction materials (quarries (tajos)), when they were established prior to the declaration of the CNE Board of Directors and do not involve a concentration of population greater than seven (7) people in highly vulnerable sites. The construction of new dairies, stables, or warehouses or the expansion of pre-existing ones is not permitted. Existing facilities for forestry, agricultural, and livestock services, and material extraction (provided they have the respective permits), may be repaired.
2°—Restrictions for the visit and transit of people.
While the Arenal Volcano remains active with the emission of lava flows (coladas de lava), pyroclastic flows (flujos piroclásticos), ash, and volcanic gases, the restricted area will be divided into two subzones regarding the visit of people and transit (figure 2).
2.1 Subzone of absolute prohibition of the visit and transit of people: (Sub-1) Access to this zone should only be permitted for people who meet the following requirements; a. Volcanology research in the service of national public or private institutions or foreign scientists accompanied by personnel from national institutions, provided they carry identifications accrediting them as such.
b. Officials from emergency response institutions conducting salvage or rescue operations, or surveillance and monitoring, provided they carry identifications accrediting them as such.
c. Police authorities performing arrest operations or judicial investigations, provided they carry the corresponding identifications.
2.2 Subzone of partial restriction of the visit and free transit of people: (Sub-2) Visiting the lower portion of the volcano's western flank and the lands located to the west of it, between the Arenal Conservation Area and the Arenal Lagoon and the Arenal River, will only be permitted under the following conditions; a. The controlled entry of small groups of people (10) to the Arenal Conservation Area (ACA) will be permitted, for a limited time and under the strict supervision of ACA officials, up to the sector delimited by the 600 masl contour line, a limit that must be properly marked by the officials of this institution.
b. The ACA must have an alarm system to order evacuations, evacuation plans duly approved by the CNE, and people must not spend the night or camp within it. The only tourist service that may occur within this zone is that of a tourist guide for groups of people, as well as transportation to and from the zone.
These guides must be duly certified by the Costa Rican Tourism Institute (ICT).
c. The road that crosses the foot of the volcano's western flank will be free-circulation; however, it is recommended to establish a controlled vehicular flow, as well as the installation of informative barriers regarding the different restrictions that exist in the zone.
d. The lands located between the road and the Arenal Reservoir and the Arenal River may be visited to carry out the activities indicated for Restriction Zone 3, R3, of the aforementioned section 1.2.
Likewise, it must be clarified to people and property owners, as well as to ACA officials with activities within the red zone or absolute restriction zone, that this area possesses a high risk, and therefore it must be properly demarcated and posted, or if applicable, fenced.
Eduardo Malavassi V. Dr. Guillermo Alvarado I.
OVS1COR1-UNA OSTVAM-ICE M.Sc. Sergio Paniagua P. M.Sc. Lidier Esquivel V.
RSN/ICE-UCR C.N.E.
RESTRICTIONS FOR LAND USE IN THE SURROUNDINGS OF THE ARENAL VOLCANO September, 2000 The Arenal Volcano (1633 masl) is located in the canton of San Carlos, La Fortuna district, Province of Alajuela.
The research carried out defines it with a maximum age of about 7000 years, therefore all geoscientists agree that geologically it is a very young volcano, and whose eruptive dynamics are extremely high, currently making it one of the most active and dangerous volcanoes in America.
The volcanic massif and its eruptive manifestations, practically constant since 1968, have become one of the country's top tourist attractions, especially since 1991, both for the spectacle that the volcano with its activity represents, and for the abundant hot springs that exist in the surroundings and other aspects of the landscape and facilities the region offers.
Alongside this activity, other services offered in the place have emerged, such as horseback riding, bicycle rides, and excursions by guides from both legally established and improvised companies, among others.
The rate of infrastructure construction (mainly cabins, hotels, spas, and restaurants) is extremely high, some of which have inevitably been installed on areas of imminent volcanic threat.
Adding to this situation are a significant number of projects currently at the proposal level or starting the first construction phases, some of them extremely ambitious, with a concerning tendency to approach sites that have historically remained unoccupied and are of high threat.
In terms of volcanic research and surveillance, it is recognized that although this is one of the best-monitored volcanoes, both for the technology used and the density of instruments installed in its surroundings, the level of knowledge of this type of process is limited, being a significant obstacle to having an efficient early warning system and thus evacuating vulnerable sites with sufficient time, which could prevent unfortunate accidents.
However, on the other hand, the research carried out and the products obtained from it favor, with an adequate level of security, identifying areas that within a relatively short timeframe (weeks, months, or years) may be affected by one or another phenomenon resulting from this continuous volcanic activity.
Based precisely on this information, the Volcanological and Seismological Observatory of Costa Rica (OVSICORI-UNA), the National Seismological Network (RSN-UCR-ICE), the Volcanological and Seismological Observatory of Arenal and Miravalles (OSIVAM-ICE), and the National Commission for Risk Prevention and Emergency Response (CNE), and in accordance with the powers granted by Law No. 7914, make the following proposal for land-use regulation, which must be taken into account from this moment on, for any development intended to be carried out in the zone, whether of a tourism nature, any other productive sector, or public, with the aim of controlling the growing risk levels present in this region, and for the sake of improving the future distribution of said activities, in line with the threat level that must definitively be respected in the influence zones of the Arenal Volcano.
It is also valid to recognize that despite the complexity that delimiting threat levels in this sector may represent, an effort has been made to simplify the zoning, so that oversight can be carried out by technical personnel from institutions that, due to their functions, must perform a control role through the issuance of construction or operating permits.
First level of limitation:
5.5-kilometer Criterion:
A first level of control is proposed, which establishes that any development intended to be carried out within a radius of less than 5.5 kilometers measured horizontally from the upper crater of the Arenal Volcano, as well as along the rivers, streams (quebradas), or channels that have their headwaters at the summit of said volcanic cone, must necessarily include an assessment of the project's risk level, carried out by a competent professional. This research must be endorsed by any of the Volcanic Research Centers in the country and countersigned by the CNE.
To establish the massive setbacks from the volcano's summit, factors related both to the historical eruptive activity of this apparatus and to morphological aspects that may determine the direction and reach of any volcanic process have been considered.
The distance (5.5 Km.) corresponds to the maximum number of kilometers that a lava flow or pyroclastic flow produced by the lateral collapse of a lava front or the crater wall has managed to travel, plus one kilometer as a safety margin, due to the eventuality that in the future more favorable conditions might arise for this displacement to reach further than established, and also to protect the site from eventual collateral effects such as forest fires or high-temperature gas flows.
On the other hand, this condition is established for those channels that have their headwaters in the upper part of the volcanic massif, given the possibility that their valleys serve to channel the volcanic phenomena, as has occurred in contemporary events presented in this sector.
Other types of dangers, such as the fall of pyroclasts (piroclástos) (fragments) of large or medium sizes, are contained within this area.
Second level of limitation:
No-construction area and restriction of human activity (absolute reserve) Within the aforementioned circle of 5.5 Km. around the crater, an area has been identified in which, due to its very high level of exposure to the volcanic threat, the presence of adverse topographic conditions, legal limitations (such as territories of the Arenal Conservation Area -ACA-), or the existence of primary forests, deserve to be considered absolute reserve areas (no construction and restriction of human activity).
In this zone, under no circumstances should permits be granted for the development of new tourist projects (or expansions of existing ones), or any other activity; the growth of already established projects must be definitively halted and other options sought outside said area for future growth.
Within it are the channels of the main streams (quebradas) that have their headwaters in said volcano, all the flanks of the cone from its base, and the entire western flank of the volcanic apparatus, practically to the Arenal lagoon.
Likewise, the possibility is considered that in the future, the evolution of the volcanic activity may expose flanks that to date have not been permanently or directly affected.
Final comments.
These regulatory measures aim to not encourage development poles in areas that have been previously determined as high-risk, and on the other hand to facilitate that the Arenal Conservation Area becomes an instrument not only for environmental conservation but also for containment to prevent the use of the already mentioned areas.
Along with these regulations, business owners in the tourism sector must be requested to have contingency business plans, demarcation of evacuation routes, trained officials to handle possible preventive evacuations, and other measures deemed pertinent.
Weaknesses have also been detected in the supply of information to visitors, related to the volcanic threat and the limits that must be respected and measures to be taken in case of a volcanic eruption. It is also necessary to demarcate again with signs (if possible georeferenced by GPS) in several languages (at least English/Spanish) indicating the maximum recommended approach limits.
Likewise, it is important to be clear that this zoning can be expanded depending on the evolution of the volcanic threat, with the possibility that areas not currently contemplated as high-risk may, in the future, depending on the circumstances, need to be contemplated as protection areas.
Eduardo Malavassi Guillermo Alvarado I.
OVSICORI-UNA OSIVAM-ICE Sergio Paniagua P. Lidier Esquivel V.
RSN/ICE-UCR C.N.E.
With no further business to discuss, the session is adjourned at ten o'clock on Wednesday, December sixth, of the year two thousand.