Outdated regulations and institutional vulnerability: Hydrological risk management in Málaga's municipal planning

Abstract

Málaga, a Mediterranean region, is increasingly prone to water-related risks, a situation compounded by the impacts of climate change. Urban development practices over the past decades have significantly exacerbated these risks. Our study offers a novel, scientifically derived methodology to evaluate municipal capabilities in managing hydrological risks through urban planning instruments. Leveraging a checklist applied through multicriteria analysis, we scrutinized the integration of theoretical and regulatory frameworks relating to hydrological risks in numerous municipalities. Our findings highlight a glaring deficiency in local Disaster Risk Reduction strategies in alignment with the Sendai Framework. Additionally, there's minimal incorporation of natural risk analysis and mapping into planning instruments. Our results spotlight Málaga's high institutional vulnerability due to its limited capacity in hydrological risk management, underlining the pressing necessity for land use policies informed by risk assessments and prioritizing citizen safety. This study significantly contributes to future urban planning initiatives, offering a roadmap toward more resilient communities amid escalating hydrological risks.

Graphical abstract

1. Introduction

Despite the universal acceptance of risks—whether natural, induced, or technological—it's clear that regions and their planners vary widely in their capacity to tolerate and manage these risks. This variability is evident when examining hydrological risks, where the risk appetite should, in theory, be far lower than the uncertainty level of statistical models [1]. This is essential for ensuring the safety of people, their assets, and livelihoods against potentially catastrophic, often irreversible, events. Importantly, current urban planning must be rigorously scrutinized to assess its capacity to offer protection against hydrological risks, considering the lengthy approval and validity periods of these plans. In this context, we have developed and applied a scientific approach, including an evaluation of institutional vulnerability to measure urban planning's performance in mitigating hydrological risks.

This study's primary objective is to evaluate urban planning performance against hydrological risks in the Málaga municipalities, notably vulnerable to such risks. We build our theoretical framework for hydrological risks on timely and relevant publications, considering territorial scope, methodology, and hydrological risk management. Also, we integrate perspectives from over 200 scientists, policymakers, and professionals from the “Science for Disaster Risk Management” guide [2]. Our regulatory framework consulting consolidates current legislation, and key judgments help define indicators for our checklist. We exclude regulations related to response and emergency phases from our analysis, focusing instead on disaster risk prevention within local administrations' urban planning competence.

We heed the European Committee of the Regions call in their 2017 Opinion on the Sendai Framework for Disaster Risk Reduction 2015–2030 Action Plan, which advocates adopting a risk-informed approach to all Union policies. This highlights the urgency of addressing hydrological risks in territorial planning, a task within local administrations' purview that can be coordinated with other competent authorities. The urgency of this issue and the expected necessary steps in the years to come underline this study's importance and relevance.2

2. Regulatory framework

2.1. Sendai Framework for Disaster Risk Reduction

In addition to Spain, 192 states and stakeholders currently subscribe to the Sendai Framework for Disaster Risk Reduction (DRR), an instrument conceived for its application to disaster risks at all spatiotemporal scales, regardless of their origin. The framework has seven goals connected to the Sustainable Development Goals (SDGs) through a series of common indicators, 11 of which are related to goals 1, 11, and 13, which are part of the United Nations Office for Disaster Risk Reduction (UNDRR) monitoring system.

This work specifically evaluates the implementation of Goal E, which refers to DRR strategies at the local level that should be in place since 2020. It is also important to note that underlying factors such as poverty, inequality, policies formulated without knowledge of risks, demographic changes and land use, epidemics and pandemics, etc., mean that both the causes and scope of disasters are interconnected, limiting, and even capable of reversing progress in achieving SDGs other than those monitored by UNDRR.

2.2. Binding regulations for general plans

Regarding the binding regulations on which the checklist for this work is based, it should be highlighted that Directive 2000/60/EC, or the Water Framework Directive (WFD) [3], and Directive 2007/60/EC, or the Floods Directive [4], are of fundamental importance. The WFD is reflected in national law by the Consolidated Text of the Water Law, approved by Royal Legislative Decree 1/2001, of July 20 (TRLA), as well as by the legal framework for water planning. On the other hand, the Floods Directive is transposed into Spanish law by Royal Decree 903/2010, of July 9, on the assessment and management of flood risks. At the regional level, Law 9/2010, of July 30, on Water in Andalusia [5], is the legal framework that applies to general urban development plans (PGOUs), together with the specific legislation on territorial and urban planning. Among the latter, the specific law governing territorial planning in Andalusia is currently Law 1/1994, of January 11, on Territorial Planning in the Autonomous Community of Andalusia (LOTA) [6]. This law provides that territorial planning must be carried out through the Territorial Plan of Andalusia (POTA) [7], the Plan for the Protection of the Coastal Corridor of Andalusia [8], and the Territorial Plans of subregional scope. The POTA must indicate the areas with catastrophic risks and define the territorial criteria for action to be taken to prevent them, considering the applicable policies of the European Union and the State. This Plan is binding for all other territorial planning instruments, plans with an impact on territorial planning, and general urban planning.

Similarly, LOTA provides that the Plan for the Protection of the Coastal Corridor of Andalusia must include, among other things, the designation of areas that must be preserved from urban development for territorial or protection reasons. This plan is also binding for subregional Territorial Plans. The scope of this plan includes at least the first 500 m of the Coastal Influence Zone, as well as any other areas necessary to achieve the protection and accessibility objectives of the coastal system of the municipalities of Málaga.3

Subregional Territorial Plans are binding for plans with an impact on territorial planning and general urban planning. They must also include the determinations of plans with an impact on territorial planning (including water management plans, plans for the management of natural resources, and the Andalusian Climate Action Plan) and of the urban plans in their scope that must be adapted, justifying any proposed changes to them. The aforementioned determinations can be rules (with direct binding effect), guidelines (binding in terms of their objectives), or recommendations (non-binding), but any deviation from them requires explicit justification and must be compatible with the objectives of territorial planning.

Regarding its processing, the approval of Territorial Planning Plans implies the declaration of public utility and the need for the occupation of the corresponding assets and acquisition of rights, for expropriation, temporary occupation, or imposition or modification of servitude. Likewise, the Government Council has the power to declare of Autonomous Interest the public actions contemplated in territorial planning plans and plans with territorial incidence. In this sense, the PGOUs, their total or partial revisions, and modifications of the structural planning must be submitted after the initial approval to a binding report on the territorial incidence that includes the analysis of the compatibility of this with the determinations of the territorial planning instruments.

As stated in the preamble of Law 7/2002, of December 17, on Urban Planning in Andalusia (LOUA) [9], since the transfer of means for exercising urban planning competencies to the Autonomous Community of Andalusia in 1979, the regional government has pursued a decisive policy of promoting urban planning. Additionally, LOUA explicitly states that regardless of private sector involvement in direct implementation, urban planning activity, and plan execution are a public function, hence the public administration is responsible for its direction and control. Based on these competencies, Andalusian urban planning legislation is developed, which at the municipal level translates into general urban planning figures.

On the other hand, territorial and urban planning instruments are subject to environmental evaluation by the provisions of the legislation on the evaluation of the effects of certain plans and programs on the environment, without prejudice to the environmental impact assessment of the projects required for their implementation, if applicable. In this sense, Andalusian regulations are based on Law 7/2007, of July 9, on Integrated Environmental Quality Management (GICA) [10]. This law includes the regional competencies statutorily attributed to the areas of the environment, protected areas, and sustainability, including the regulation of environmental evaluation of plans and programs. Therefore, in addition to considering applicable directives such as the WFD, the GICA is developed based on the state basic legislation, which includes Law 21/2013, of December 9, on environmental evaluation (LEA) [11], and the Consolidated Text of the Land and Urban Rehabilitation Law (TRLS), approved by Royal Legislative Decree 7/2015, of October 30.

Specifically, the environmental evaluation of urban planning instruments is carried out following the procedures and requirements of the evaluation of plans and programs, with the particularities derived from the provisions of LOUA. This work does not aim to provide a detailed explanation of Strategic Environmental Assessment (SEA) or its legal regime; it simply states that planning instruments may be subject to ordinary or simplified SEA, considering the assumptions established by this law. In any case, modifications affecting the structural planning relating to non-developable land (classification, category, etc.) are subject to ordinary SEA. Furthermore, the Environmental Impact Study (EIS) of urbanization action planning instruments must include, among other aspects, a map of natural risks in the area subject to planning, as well as the short-, medium-, and long-term impacts of climate change, integrating the secondary, cumulative, and synergistic effects of the project on the population and the environment.

In summary, among the binding regulations that influence urban planning concerning hydrological risk, the WFD and the Floods Directive play a crucial role. Both directives, implemented through the Spanish national law and regional Andalusian law, mandate specific provisions that are instrumental in PGOUs. Despite the regulations' potential for directing urban planning towards a safer, risk-informed approach, the study found that the application and enforcement of these mandates have been inconsistent, contributing to the hydrological risk Málaga currently faces. The examination of these regulations, considering the results from the studied municipalities, offers an important perspective on the enforcement and effectiveness of these laws.

3. Methodology

This research employed a comprehensive methodology to evaluate hydrological risk management strategies in fourteen municipalities in Málaga, primarily characterized by exposure to natural hazards such as fluvial floods [12], soil erosion, and potential for mass movements.

The initial stage involved an in-depth analysis of normative and jurisprudential frameworks, as well as a detailed assessment of territorial hydrological risks. The municipalities of Algarrobo, Benamargosa, Rincón de la Victoria, Vélez-Málaga, Estepona, Fuengirola, Marbella, Mijas, Torremolinos, Málaga, Alhaurín de la Torre, Cártama, Coín, and Pizarra were selected for this purpose. The selection criteria included the use of official cartographic data and other relevant information obtained from REDIAM,4 and the National Soil Erosion Inventory of the Ministry for Ecological Transition and the Demographic Challenge [13].

The collected data were systematically processed using QGIS 3.10, a well-known open-source Geographic Information System software. To allow comparability, the data were normalized for the 103 municipalities within the province and filtered according to pre-determined criteria. Notably, the chosen municipalities had at least 3% of their territories located within flood-prone zones, more than 9 t ha⁻¹·year⁻¹ affected by soil erosion and a minimum of 36% of the territory with a high to very high potential for mass movements.

Standard forms were devised to incorporate critical information about each municipality to facilitate an in-depth evaluation. The forms included population density, recorded flood and gravitational events, inequality indices, and other relevant land-use indicators. Additionally, these forms had a section dedicated to observations and a provision to calculate a “Municipal Plan Performance Value” - a quantifiable measure indicating the outcome of this study. An illustration of such a form for the Pizarra municipality is provided in Fig. 1.5

Fig. 1.

Municipality sheet example (results from Pizarra). Own Elaboration.

The subsequent phase revolved around the design of a comprehensive checklist, instrumental in evaluating each municipality's risk management capabilities. The checklist, detailed in Table 1, comprises 20 compliance indicators: 9 associated with binding legislation, 3 linked to community regulations, and 8 related to the Sendai Framework for Disaster Risk Reduction [14]. A more in-depth explanation of these indicators and specific evaluation criteria is provided in the Supplementary Material accompanying this paper.

Table 1.

Checklist. Own elaboration.

CHECKLIST
I.	Binding legislation
1.	Determination and delimitation of the Hydraulic Public Domain (DPH) and the Maritime-Terrestrial Public Domain (DPMT) (if applicable), intense drainage routes, and return periods (T).
2.	Includes adaptation of buildings and other land uses considering natural flood risk maps.
3.	Analysis and mapping of natural risks. Within the corresponding Environmental Impact Study (EIS) and incorporated into the planning instrument.
4.	Addresses the repercussions of climate change on the incidence of natural risks.
5.	Preserves the urban development process for the land adjacent to the natural public domain to ensure its integrity (minimum easement margins of 5 m and police margins of 100 m in DPH).
6.	Preserves the urban development process for the land that presents natural risks.
7.	Includes specific structural measures for flood risk management.
8.	Includes specific non-structural measures for flood risk management.
9.	Includes corrective (elimination) measures for constructions in flood-prone areas.
II.	Community Regulations
10.	Establishes additional protection standards against hydrological disaster risks.
11.	Risk maps include coastal (if applicable), river, and flash flood risks.
12.	Risk maps identify and include other risk multiplier elements of flooding (transported sediments, rockfalls, etc.).
III.	Sendai Framework for DRR
13.	Recognizes the types of hydrological risk present.
14.	A multiple risk assessment has been carried out.
15.	Incorporates present hydrological risks into land use planning (zoning).
16.	Recognizes and incorporates scientific uncertainty from the precautionary principle.
17.	Contemplates the revision, adaptation, and updating of the planning with future changes in projected risks.
18.	Includes structural measures for managing present hydrological risks.
19.	Includes non-structural measures for managing present hydrological risks.
20.	Includes a local strategy for DRR (2020-Meta E, SDGs 1.5, 3.d, 11.5, 11. b, 13.1, and 15).

Ensuring the consistency of the applied indicators was achieved through a multi-criteria analysis, which entailed a pairwise comparison of indicators to establish their relative importance (see supplementary material, Annex 2).

The evaluation process comprised an audit of each general urban planning plan against the established indicators. The scoring system rated full compliance as (5), partial compliance as (3), and non-compliance as (0). The weighted ratings summed up to generate a ‘global performance value’ ranging between 0 (null performance) and 500 (optimal performance).

The final stage involved the assimilation of results into each municipality's profile, to inform multi-scale decision-making. Qualitative assessments were used in conjunction with the numerical performance values to yield a well-rounded understanding of each municipality's risk management performance. The performances were categorized as deficient (0–124), insufficiently compatible (125–249), moderately compatible (250–374), and adapted compatible (375–500). This standardized evaluation process facilitated an objective comparison across the case studies. A step-by-step graphical representation of the methodology can be found in the supplementary materials.

4. Results and discussion

Table 2 depicts the performance value of each municipal plan, showing that 10 out of 14 municipalities are deficient, three are insufficiently compatible, and only one is moderately compatible.

Table 2.

Performance value of each Municipal Plan.

Municipality	Index	Qualification
Pizarra	310	Compatible – Moderate
Torremolinos	256	Compatible – Insufficient
Málaga	207	Compatible – Insufficient
Fuengirola	207	Compatible – Insufficient
Vélez-Málaga	71	Deficient
Algarrobo	56	Deficient
Cártama	44	Deficient
Marbella	35	Deficient
Mijas	25	Deficient
Coín	22	Deficient
Estepona	20	Deficient
Alhaurín de la Torre	2	Deficient
Benamargosa	0	Deficient
Rincón de la Victoria	0	Deficient

Given the volume of data analyzed, the following results have been organized into four main categories: binding legislation, community regulations, Sendai Framework, and specific measures for flood risk management and hydrological risks.

4.1. Binding legislation (indicators 1–6, and 9)

Indicator 1: Technical Determination and Delimitation of DPH and DPMT, Intense Drainage Routes, and Return Periods.

Compliant Municipalities: Fuengirola, Torremolinos, Málaga, and Pizarra comply sufficiently with this indicator. They all designate DPH and DPMT to non-developable land under special protection (SNU-EP), following specific legislation. Among them, Fuengirola and Pizarra recognize a wider range of return periods, with Pizarra acknowledging the highest (1000 years). Nevertheless, none of these municipalities have technically determined the intense drainage routes.

Partially Compliant Municipalities: Algarrobo, Vélez-Málaga, Estepona, Marbella, Mijas, Alhaurín de la Torre, Cártama, and Coín are partially compliant. They account for DPH and DPMT but lack their technical delimitation. Particularly, Vélez-Málaga, Algarrobo, and Mijas classify these lands as General Systems, rather than SNU-EP, which may not offer sufficient guarantees of protection against potential hydrological risks.

Key Issues: The classification of certain lands as General Systems instead of SNU-EP and the lack of legal authorization cited in Mijas’ case raise questions about the robustness of the protection offered. It suggests that local administrations might need to better utilize their authority to review and update their general plans by higher-ranking binding legislation.

Indicator 2: Adaptation of Buildings and Land Use Considering Natural Flood Risk Maps.

Compliant Municipalities: Torremolinos and Pizarra stand out for their full compliance. Torremolinos implements a Corrective Flood Risk Action Plan in urban areas, even classifying incompatible lands as out of order. Pizarra classifies structures affected by flood risk as subject to a temporary out-of-order regime. It allows only conservation and rehabilitation works until flood defence measures are enacted, after which the buildings are deemed orderly.

Partially Compliant Municipalities: Vélez-Málaga, Fuengirola, and Málaga demonstrated partial compliance. Vélez-Málaga's plan lacks determination of associated risk and spatiotemporal scope for its Special Plans designed to restore non-developable land to agricultural use. Fuengirola's plan addresses land use according to areas assigned to different flood risk categories but doesn't explicitly provide for the adaptation of existing buildings. Málaga's General Urban Plan also lacks specific adaptation actions for existing buildings. However, it mandates that flood-prone areas be kept free from construction, buildings, and infrastructure.

Key Issues: A key issue lies in the absence of clear provisions for adapting existing buildings in Fuengirola and Málaga. It's crucial to address this aspect to enhance resilience against potential flood risks. For Vélez-Málaga, a better articulation of the risk and scope associated with each Special Plan is required to improve planning clarity. Pizarra's approach of a temporary out-of-order regime for buildings at risk could be a valuable strategy for other municipalities to consider.

Indicator 3: analysis and mapping of natural risks.

Compliant Municipalities: Málaga and Pizarra show sufficient compliance with indicator 3. Pizarra's General Urban Development Plan (PGOU) incorporates comprehensive annexes, including an Environmental Study, Environmental Risk Study, and Hydrological-Hydraulic Study. The findings of these studies are cohesively integrated into both the territorial planning memory and the general plan's urban regulations. Although Málaga's EIS does not specifically conduct a natural risk analysis, factors such as floodability and terrain instability are considered. Málaga also provides an annexed hydrological and hydraulic study integrated into its water mapping, demonstrating its consideration for natural risks.

Partially Compliant Municipalities: Fuengirola and Torremolinos show partial compliance. Fuengirola's environmental study considers geological and flood risks but lacks associated risk mapping. Torremolinos' EIS, while not providing a comprehensive natural risk analysis, includes a hydrological and hydraulic study that delineates flood risk for a 500-year return period. However, it does not consider other present hydrological risks, thus earning it a partial compliance status.

Key Issues: One common issue across these municipalities is the limited scope of risk analysis. Specifically, not all municipalities comprehensively consider various forms of natural risks, often omitting certain categories of hydrological risks. Also, while some municipalities include studies that consider different aspects of natural risks, these are not always adequately translated into risk maps, which are crucial for practical implementation and decision-making in urban planning.

Indicator 4: Treatment of the Effects of Climate Change on the Incidence of Natural Risks.

Compliant Municipalities: In the evaluated municipalities, only Torremolinos satisfactorily integrated the impacts of climate change into its 2020 PGOU. The municipality did so via its Twelfth Additional Provision and an addendum to its Environmental Impact Study (EIS), outlining climate change mitigation and adaptation measures.

Partially Compliant Municipalities: Notably, no other municipalities were found to be partially compliant for this indicator. Their urban planning schemes lacked the incorporation of climate change impacts, revealing a significant gap in addressing and managing evolving environmental hazards [15].

Key Issues: The overarching issue identified was that most municipalities were not recognizing or planning for the increasing risks associated with climate change. Despite Torremolinos demonstrating some level of commitment to tackling climate change, the measures outlined lacked specificity towards individual natural risks. However, due to their broad applicability (encompassing ecosystems, water, and land occupation patterns), these strategies were considered sufficient in this evaluation. Their acknowledgement of the necessity to “define the risk zones against intense climatological phenomena, especially flooding and increased erosion” was a promising step, highlighting the municipality's awareness of climate change's multifaceted impacts. This indicator underlines a crucial area for improvement for most municipalities.

Indicator 5: Preservation of the urbanization process for the urban development of lands adjacent to the natural public domain.

Compliant Municipalities: Fuengirola, Marbella, Torremolinos, and Pizarra demonstrated adequate preservation measures for the urban development of lands adjacent to the natural public domain. They have considered compatibility with sectoral legislation, regulating areas of servitude, police, and floodable zones. Marbella and Pizarra have also implemented an additional protection zone alongside rivers and streams. Torremolinos has specific conditions for developable and urban land, planning more precise measures through the Plan for Corrective Flood Risk Actions in the urban centre of Torremolinos.

Partially Compliant Municipalities: Málaga and Coín demonstrated partial compliance with the preservation of the urbanization process. While Málaga considers legislation to protect lands assigned to non-developable areas under special protection (SNU-EP), it transfers responsibility for protection to structural solutions established in development projects. This evaluation interprets Málaga's regulatory provisions as discretionary, providing partial protection to areas adjacent to the public domain. Meanwhile, Coín's Partial Adaptation Plan does not include areas adjacent to channels assigned to non-consolidated or non-developable urban lands. Coupled with the lack of delimitation for specific streams, this leads to partial fulfilment of indicator 5.

Key Issues: Notably, the evaluation reveals a concerning discretionary aspect to the preservation measures in Málaga. Also, in Coín, the lack of areas adjacent to channels assigned to non-developable urban lands in their zoning maps presents a significant issue.

Indicator 6: Preservation of Urbanization Process in Lands Presenting Natural Risks.

Compliant Municipality: Pizarra stands as the only municipality that fully satisfies the criteria of indicator 6, preserving the urbanization of lands presenting natural risks comprehensively.

Partially Compliant Municipalities: Fuengirola, Torremolinos, and Málaga demonstrate partial compliance. While the General Urban Plans for Torremolinos and Málaga incorporate specific measures to limit golf course development in areas presenting gravitational risks, neither explicitly address the preservation of lands facing other natural risks apart from pre-identified flood areas. Fuengirola's General Urban Plan, aside from highlighting certain flood risk points like the Real Stream and the Fuengirola River, does not specifically address preservation against other natural risks. However, its Plan provides technical guidelines for development areas, ensuring that areas with slopes greater than 35% are preserved from construction and that deep cuts in the landscape are avoided.

Key Issues: A notable gap in the strategies of these municipalities is the lack of comprehensive planning for a range of natural risks. Emphasis is generally placed on identified flood areas, with insufficient attention given to other potential risks. Moreover, explicit provisions for preserving the urbanization process in lands with natural risks are largely absent from the General Urban Plans of Torremolinos and Málaga. Fuengirola's approach, though acknowledging some additional constraints for certain development areas, falls short of a holistic risk mitigation strategy. These shortcomings highlight the need for a more comprehensive approach to urban planning in areas presenting diverse natural risks.

Indicator 9: Correction Measures (Elimination) of Constructions in Flood-Prone Areas.

Compliant Municipalities: There are no municipalities that comply with the criteria of indicator 9.

Partially Compliant Municipalities: Not applicable, as no municipality considers the implementation of corrective measures to eliminate constructions in flood-prone areas.

Key Issues: This result underscores a critical gap in the urban planning strategies of all the studied municipalities. Not considering the elimination of structures in flood-prone areas fails to acknowledge the potential for significant damage and loss in these high-risk zones [16]. This absence of corrective measures indicates a lack of comprehensive disaster risk management strategies in these municipalities, highlighting an urgent need for reconsideration of policies for a proactive approach towards urban resilience.

4.2. Community regulations (indicators 10 to 12)

Indicator 10: Establishment of Additional Protection Rules Against Hydrological Disaster Risks.

Compliant Municipalities: The municipalities of Fuengirola, Torremolinos, Málaga, and Pizarra have all incorporated a heightened level of protection exceeding that mandated by sectorial legislation into their planning. Fuengirola notably defines the Pajares Stream and Carvajal Park as “Spaces of High Ecological Value”, and mandates a thorough geomorphological study and approval from a geological institute before any development activities in “Geological Protection Areas”. Torremolinos and Málaga have implemented special conditions for development on plots near the DPH, in areas prone to flooding, or on steep slopes. Pizarra has imposed specific use rules and limitations on the SNU-EP, which are based on the prevalent natural risks identified.

Partially Compliant Municipalities: No municipalities have been identified as partially compliant with indicator 10 in this study.

Key Issues: The need for more comprehensive regulations addressing hydrological disaster risks is evident. A lack of additional protection rules can compromise the safety of people and assets in the face of potential hydrological hazards. The provisions adopted by the compliant municipalities serve as promising examples that could be emulated by others. Fuengirola's model of designating special areas and mandating thorough geological assessments can help ensure environmentally sensitive areas are not inadvertently compromised, while the practices in Torremolinos, Málaga, and Pizarra demonstrate how additional rules can mitigate risk in flood-prone and steep areas.

Indicator 11: Cartography of Coastal, River, and Flash Flood Risks.

Compliant Municipalities: Fully compliant municipalities are not found for Indicator 11.

Partially Compliant Municipalities: Vélez-Málaga, Torremolinos, Málaga, and Pizarra have partially complied with Indicator 11. Their efforts in this regard have led to the development of cartography for coastal, river, and flash flood risks, albeit with some limitations. Notably, their preparedness does not extend to non-riverine flash floods, a potential shortfall in their risk management.

Key Issues: A significant limitation across these municipalities is the exclusion of non-riverine flash floods from their planning instruments, which could leave these areas unprepared for such events. Additionally, coastal floods were not considered by Vélez-Málaga and Torremolinos. This lack of comprehensive risk mapping in these municipalities exposes them to potential vulnerabilities. Therefore, further work needs to be undertaken to ensure all forms of flood risks are appropriately mapped and planned for.

Indicator 12: risk multiplier elements of flooding.

Compliant Municipalities: No municipalities fully complied with Indicator 12, regarding the inclusion of flood risk multiplier elements such as transported sediments and debris flows in their risk maps.

Partially Compliant Municipalities: Not applicable.

Key Issues: This total non-compliance with Indicator 12, the ninth most important in this study, reveals a significant gap in flood risk assessment. The absence of this factor could potentially lead to an underestimation of flood risks and insufficient preparation or mitigation measures, leaving communities vulnerable to unexpected hazards during flood events. This issue needs to be addressed urgently to enhance the resilience of these municipalities to flood disasters.

4.3. Sendai Framework for DRR (indicators 13–17, and 20)

Indicator 13: Recognition of Hydrological Risk Types.

Compliant Municipalities: The municipalities of Algarrobo, Fuengirola, Torremolinos, Málaga, Cártama, and Pizarra all reflect the diverse hydrological risks including flooding, erosion, and climatic events, in their respective planning documents. Particularly, Cártama's structural analysis incorporates an in-depth geological report, recognizing flooding risks and the potential for landslides and terrain instability.

Partially Compliant Municipalities: Estepona only acknowledges river flooding risks, as identified by the Plan for the Prevention of Floods in Andalusian Urban Channels and the Andalusian Water Agency. This partial compliance is of particular concern given that over 85% of the Estepona territory is potentially exposed to a high or very high risk of mass movements.

Key Issues: Despite some municipalities demonstrating an awareness of multiple hydrological risks, many fall short of translating this recognition into tangible regulatory or zoning provisions for land use planning. This disconnection between the identification of potential hazards and the implementation of effective preventative measures presents a significant barrier to comprehensive disaster risk reduction.

Indicator 14: multiple risks assessment.

Compliant Municipalities: None of the municipalities studied carried out assessments of multiple hydrological risks, failing to fulfil the requirements of this indicator.

Key Issues: The absence of multiple risks assessment across all municipalities presents a serious gap in the holistic understanding of hydrological hazards. It prevents the development of comprehensive and effective land use planning strategies, potentially compromising safety and sustainability.

Indicator 15: Incorporation of Hydrological Risks into Land Use Planning.

Compliant Municipalities: Pizarra is the sole municipality that successfully incorporates recognised hydrological risks into land use planning, specifically through establishing appropriate zoning strategies.

Key Issues: With only one municipality incorporating hydrological risks into its land use planning, there is a significant shortfall in disaster risk reduction efforts. This lack of integration suggests a need for a more thorough, risk-informed approach to planning that includes comprehensive zoning strategies to mitigate the potential impacts of hydrological hazards.

Indicator 16: Recognition and Incorporation of Scientific Uncertainty in the Precautionary Principle.

Compliant Municipalities: Pizarra is the only municipality that implicitly incorporates this precautionary principle in its planning. This is evident in its preservation of new developable sectors in areas where there's a potential for natural or artificial risks, even though it does not explicitly recognize the uncertainty tied to projected hydrological risks.

Partially Compliant Municipalities: There were no municipalities identified as partially compliant with this indicator.

Key Issues: The lack of explicit recognition of scientific uncertainty in most municipalities' planning is a key issue. According to the Sendai Framework for DRR, ideally, uncertainty related to hydrological risk models [17] would be integrated into planning, with redefined scenarios that consider potential unprecedented extreme events. The current municipal plans do not meet this standard. The unique approach of Pizarra underscores the need for other municipalities to follow suit in acknowledging and planning for scientific uncertainty in hydrological risks.

Indicator 17: Updating Urban Planning Schemes Based on Projected Risks.

Compliant Municipalities: None of the municipalities considered future changes in projected risks an explicit reason for revising, adapting, or updating their urban planning scheme.

Algarrobo, Vélez-Málaga, Estepona, and Torremolinos consider revising their urban planning based on unforeseen events impacting their plans, primarily linked to demographic or economic factors. Fuengirola, Málaga, and Pizarra also allow for revisions if higher-level territorial plans affect their current scheme. The General Urban Planning Scheme (PGOU) of Málaga further adds the possibility of complete revision in the event of choosing a different territorial model, including the criteria for classification and protection of Non-Developable Land Subject to Special Protection (SNU-EP).

Key Issues: A critical issue identified is that urban plans generally cannot be revised based on future projected hydrological risks. This is mainly because these risks have not been integrated into most of the studied cases, and secondly, they need to be identified and incorporated into a higher-level legal instrument or provision with definitive and binding approval for the PGOU. Therefore, there is a fundamental need to align local urban planning practices with projected hydrological risks.

Indicator 20: Local Strategy for Disaster Risk Reduction.

Compliant Municipalities: Unfortunately, none of the municipalities have a local strategy for Disaster Risk Reduction, thereby making compliance in this area absent.

Partially Compliant Municipalities: Not applicable in this instance as none of the municipalities demonstrated any level of compliance with this indicator.

Key Issues: The lack of local Disaster Risk Reduction strategies across all municipalities is a significant concern. This gap suggests a substantial vulnerability to disaster risks and underscores the pressing need for local authorities to develop and implement comprehensive strategies for managing these risks effectively [[18], [19], [20]].

4.4. Specific measures for flood risk management and hydrological risks (indicators 7, 8, 18, and 19)

Concluding this study, we turn our attention to indicators that pertain to the general plans' specified measures, particularly indicators 19, 18, 8, and 7, which are noteworthy due to their interrelatedness. These are ordered in terms of their importance, from lowest to highest (refer to Annex II: Multi-Criteria Analysis).

Seven municipalities (Algarrobo, Vélez-Málaga, Fuengirola, Mijas, Torremolinos, Málaga, and Pizarra) have considered specific structural measures for flood risk management (indicator 7). The measures primarily include river channelling through urban areas and the adjustment of the rainwater drainage network. Fuengirola and Mijas also contemplate reforestation and recreational use of river banks, respectively.

These measures correlate directly with indicator 18, which addresses all hydrological risks in the area. Fuengirola, Torremolinos, and Pizarra exhibit satisfactory compliance. Measures adopted by Fuengirola include those ensuring minimal impact on soil stability during earth-moving activities. Torremolinos' PGOU proposes various measures such as retention works, hydraulic actions, and plantations in delicate areas. Pizarra's general plan incorporates actions to counter risks and environmental regeneration using bioengineering techniques.

Concerning non-structural flood risk management measures (indicator 8), Fuengirola and Cártama partially comply while Torremolinos and Pizarra comply sufficiently. Fuengirola mainly focuses on flood-prone land demarcation, whereas Cártama's measures are broader but subjectively applied and challenging to monitor. Torremolinos and Pizarra demonstrate more comprehensive compliance, outlining objectives and measures for water protection, land use regulations, and mandatory geological studies.

Furthermore, Pizarra meets the standards for indicator 19 concerning non-structural measures for all present hydrological risks. Both Torremolinos and Fuengirola also sufficiently fulfil the requirements of indicator 19. Torremolinos’ plans include defining risk zones against climatological phenomena, conducting cost-benefit studies, and recovering natural runoff channels. Fuengirola mandates that any planning permit request involving significant earth movements be accompanied by documentation ensuring minimal negative impact on soil erodibility.

In Cártama, some planning documents include measures for managing gravitational risk. However, these are limited to requiring that development plans justify land nature and establish the correct urbanization and building corrective measures. Thus, Cártama partially meets the criteria for indicator 19.

The accompanying chart (Fig. 2) offers a visual representation of the number of municipalities that fully comply, partially comply, or do not comply with each indicator, and highlights the relative importance of each indicator. The bar graphs provide a clear depiction of how each municipality is performing disaster risk reduction measures. Notably, the chart reveals disparities between the municipalities, showcasing the varying degrees of commitment and success in adopting the necessary measures. The relative importance of each indicator is also clearly communicated, helping readers to understand the emphasis placed on each area. This chart is crucial for gaining a clear understanding of where efforts need to be intensified, allowing policymakers and local authorities to strategically focus resources for improved disaster risk reduction.

Fig. 2.

Compliance Level and Relative Importance of Urban Planning Indicators in Andalusian Municipalities selected. Own-elaboration.

Further details for each municipality can be found in the appendix. These findings underline an urgent need for municipalities to improve their strategic approach to disaster risk reduction and climate change adaptation, particularly in terms of incorporating scientific uncertainty and developing local DRR strategies [21].

5. Conclusions

Our research presents a scientific method to assess the capacity for managing hydrological risks in urban planning. This method, which includes understanding the locality, designing checklists, assuring consistency, auditing planning, and informing results, has been applied across multiple municipalities. It reveals that most municipalities fall short in managing hydrological risks in their urban planning. No municipality, for example, has a local strategy for Disaster Risk Reduction following the Sendai Framework, and only 28% incorporate the analysis and mapping of natural risks in their planning instruments. Furthermore, only Torremolinos considers the effects of climate change on natural hazards in its General Plan for Urban Planning (PGOU).

The findings reveal a high institutional vulnerability to hydrological risks in the province of Málaga. A significant cause of concern is the lack of consideration of non-fluvial flash floods and a continued preference for structural measures over comprehensive, long-term solutions. Special attention needs to be given to Vélez-Málaga, Algarrobo, and Mijas due to their failure to delimit important hydrological features in their urban planning.

Informed by our findings, we recommend a shift towards more integrated and future-oriented urban planning. The adoption of a risk-informed approach to all policies is paramount. This approach aligns with the European Committee of the Regions' opinion on the Sendai Framework for Disaster Risk Reduction 2015–2030 Action Plan, issued on August 17, 2017, emphasizing the urgent need for such an approach. It calls for the prioritization of safety over development and an increased focus on non-structural measures for managing hydrological risks.

One crucial area that demands urgent attention is the territorial planning issue of not occupying areas with hydrological risks with urban land. Local administrations should address this issue in a coordinated manner with other competent authorities. By recognizing and assessing potential risks and integrating them into urban planning in a manner that aligns with state and community legislation, we can substantially improve the management of hydrological risks.

This study underscores the importance and viability of scientific methods in evaluating hydrological risk management in urban planning. The findings and recommendations presented herein contribute to the ongoing discussions on the subject and emphasize the need for urgent action. Local administrations have the competencies to address this problem, and necessary steps are expected to be taken in the coming years to ensure the safety and sustainability of our communities.

Author contribution statement

Jessica Bernal Borrego: Conceived and designed the experiments; Performed the experiments; Analyzed and interpreted the data; Contributed reagents, materials, analysis tools or data; Wrote the paper.

Data availability statement

Data included in article/supplementary material/referenced in article.

Additional information

Supplementary content related to this article has been published online at [URL].

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Appendix A. Supplementary data

The following are the supplementary data related to this article: