*Article* **Worry about Climate Change and Urban Flooding Risk Preparedness in Southern Italy: A Survey in the Simeto River Valley (Sicily, Italy)**

**Paola Nanni \*, David J. Peres, Rosaria E. Musumeci and Antonino Cancelliere**

Department of Civil Engineering and Architecture, University of Catania, 95123 Catania, Italy; djperes@dica.unict.it (D.J.P.); rosaria.musumeci@unict.it (R.E.M.); antonino.cancelliere@unict.it (A.C.) **\*** Correspondence: paola.nanni@unict.it

**Abstract:** Intensive urbanization and related increase of impervious surfaces, causes negative impacts on the hydrological cycle, amplifying the risk of urban floods. These impacts can get even worse due to potential climate change impacts. The urban areas of the Simeto River Valley (SRV), the largest river valley in Sicily (Italy), have been repeatedly hit by intense rainfall events in the last decades that lead to urban flooding, causing several damages and, in some instances, threats to population. In this paper, we present the results of a 10-question survey on climate change and risk perception in 11 municipalities of the SRV carried out within the activities of the LIFE project SimetoRES, which allowed to collect 1143 feedbacks from the residents. The survey investigated: (a) the level of worry about climate change in relation to extreme storms, (b) elements of urban flooding risk preparedness: the direct experience of the residents during heavy rain events, their trust in a civil protection regional alert system, and their knowledge of the correct behavior in case of flood, and (c) the willingness of citizens to implement sustainable drainage actions for climate change adaptation in their own municipality and real estates. The results show that more than 52% of citizens has inadequate knowledge of the correct behavior during flooding events and only 30% of them feel responsible for mitigation of flooding risk. There is a modest willingness by the population to support the construction of sustainable urban drainage infrastructures. A statistical cross-analysis of the answers to the different questions, based on contingency matrices and conditional frequencies, has shown that a greater worry about climate change has no significant impact either on the behavior of people in dangerous situations occurring during flooding events or on the willingness to support financially sustainable solutions. These results suggest that to build a higher worry about climate change and related urban flooding risk is not sufficient to have better preparedness, and that more direct educative actions are necessary in the area.

**Keywords:** risk preparedness; urban flooding; resilience; climate change adaptation; community involvement

#### **1. Introduction**

Climate change (CC) is a major societal risk issue and there are increasing calls for urgent mitigation and adaptation actions [1]. Over the last decade, many studies have highlighted the importance of adaptation by testing ecosystem-based approaches as a means of understanding and improving the integration of such approaches into climate change adaptation and mitigation strategies [2–5]. The traditional approach to urbanization based exclusively on impervious paving of surfaces and stormwater management relying on grey infrastructures (sewers), is not sustainable and thus is no longer compatible with climate change adaptation strategies [6–8]. The increasing urbanization leads to a greater share of impervious areas that result in increased flood risk and overloaded storm water pipe systems. For this reason, blue-green storm water and nature-based solutions have come to be seen as efficient measures against increasing flood risk in urban areas [9–11].

**Citation:** Nanni, P.; Peres, D.J.; Musumeci, R.E.; Cancelliere, A. Worry about Climate Change and Urban Flooding Risk Preparedness in Southern Italy: A Survey in the Simeto River Valley (Sicily, Italy). *Resources* **2021**, *10*, 25. https://doi.org/10.3390/ resources10030025

Academic Editor: Nicoletta Santangelo

Received: 17 February 2021 Accepted: 11 March 2021 Published: 14 March 2021

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

Flood risk may be defined as the product between the probability of flood hazard and the consequence of occurrence of flood event [12] according to

Flood risk = probability of flood hazard × consequence of occurrence of flood event

where consequence of occurrence of flood event is a function of hazard × vulnerability, the latter here including both exposure and susceptibility of harm. Several studies state that current understanding of flood risk focuses on two main factors: climate change and socioeconomic growth [11–13].

The risk of flooding for city population has been generally increasing in the past decades, and not sufficiently contrasted in terms of retrofitting urban drainage systems to urban expansion, mainly because of the significant monetary investments needed, which are not sufficiently stimulated by citizens and local administrators due to low awareness of the issue [14,15]. Hence, soft measures (i.e., non-infrastructural) oriented to increase risk awareness and preparedness of the population at all levels are of key importance, also given the comparatively low investments needed with respect to hard (i.e., infrastructural) urban flooding mitigation measures. In fact, education to flood risk awareness and preparedness has led to many benefits in several cases [16]. Several episodes in Italy have demonstrated that inadequate preparedness to urban flooding risk is a factor that contributed significantly to many casualties. Many news and videos show an incautious exposure to dangerous situations by people, which demonstrates their low levels of risk awareness. For instance, while torrents within a town were flooding with water levels near to the intrados of a bridge, people crossed it and stood upon it for mere curiosity and to shoot videos with their smartphones. Similar situations have occurred with respect to underpasses. As a confirmation that this issue does exist and is of particular concern, it can be mentioned that the Italian Civil Protection has promoted an educational campaign named "Io non rischio" (I don't take risks) in order to help people to understand which is the correct behavior during floods and other natural hazards (http://iononrischio.protezionecivile.it/en/homepage/, last accessed on 15 February 2021).

#### *1.1. Natural Hazard Risk and Climate Change Perception*

Early analyses of risk from natural hazards focused on the search for physical and tangible causes, while recently risk awareness has been gradually incorporated in several studies [17–21]. Focus has been put, particularly, on the risk of floods and landslides [16,22–25].

The spectrum of risk perception in natural hazards includes three distinct elements: worry, awareness, and preparedness [24,26–29]. In particular, according to [24], the following definitions can be given, which we use within this study: *worry* is the level of dread or concern associated with the given risk (climate change or urban flooding); *awareness* can be defined as knowledge or consciousness of the risk that an individual or a group of individuals is exposed to; *preparedness* is both the capability of coping with a flood throughout the inundation period, and post-flood recovery capability and strategies, and can be described in social, technical, economic and institutional dimensions.

Bubeck et al. (2012) [30] suggest that the relationship between individual flood risk perceptions and mitigation behavior is hardly observed in empirical studies. Other research has included the social perception of risk by using approaches that combine data on physical processes with individual interpretations of the risk [31–33]. At a national scale, investigators have estimated the individual and collective risk posed by landslides and floods to the population [34], though the assessment of public perception of the risk posed by landslides and floods in Italy remains mostly unexplored. A number of studies have been focused on the use of specific surveys to investigate natural hazard risk perception. For example, Avvisati et al. (2019) [17] carried out a study of multi-risk perception in 12 municipalities and 2 territorial unions of Campania Region characterized by different risks: seismic, volcanic, hydrogeological (floods and landslides). The results showed that historical memory plays a crucial role in the perception of natural hazards.

On the other hand, looking at studies related to Europe, Diakakis et al. (2018) [22] administered questionnaires to the population of the Attica Region in Greece, to obtain basic information on how individuals understand flood risk, risk mitigation and to what degree they take protection measures, investigating on which degree they trust relevant institutions and their awareness of flood warning and flood protection actions. Their results showed that respondents rank floods third in terms of importance—behind earthquakes and forest fires—among the more relevant risks in the region, despite the clear majority believed the risk is increasing, mostly due to anthropogenic factors. Responses illustrated low levels of trust in authorities and low levels of knowledge of protection actions and awareness regarding floods, as well as low levels of preparedness, in terms of undertaking private mitigation measures.

Other studies claim that the communication of information about natural hazard risks to the public is a difficult task for decision-makers. Feldman et al. (2016) [35] suggest that newer forms of technology present useful options for building disaster resilience and that age is the central factor in predicting the sources people use to receive risk information.

The literature concerning the perception of climate change has developed mainly in the last decade. S. Van Der Linden (2014) [36] claims that climate change compared with many other hazards is therefore relatively unique: not only because of its scope and breadth but also in the sense that it is not directly "situated" in our daily environment [37]. Nevertheless, an increasing amount of research has shown that people can (to some extent) accurately detect changes in their local climate and relate this perceptual experience to climate change [38]. Moreover, the rising incidence rate of extreme weather events is now increasingly being associated with climate change [39]. In fact, a number of studies have indicated that personal experience with extreme weather events is a significant predictor of climate change risk perceptions [38,40–42].

The link between the various facets of risk perception (worry, awareness, and preparedness) is difficult to capture. In particular, as reviewed by [43], the literature reports either indifference or positive association between worry about risk and preparedness against it. Hence, further contributions to this aspect are important.

#### *1.2. Aim of the Study*

This study aims at understanding, with reference to the Simeto River Valley (SRV) area in Sicily, Italy:


We also want to explore some of the links between the three listed aspects and in particular, the link between the level or worry about climate change and the short-term and long-term preparedness to urban flooding issues potentially exacerbated by climate change. To investigate these issues, a survey has been administered to the population, as part of the activities of EU LIFE project SimetoRES (www.lifesimetores.it, accessed on 15 February 2021). In order to involve all age categories of the local population, the survey has been conceived to be simple and short. Given the characteristics of the population, the survey constituted also a "hook" for involving the citizens in more intensive and active initiatives. The survey was open for about three months and 1143 responses were received, which constitutes a large dataset in comparison to many other studies. The survey, consistent with the aims of the study, was articulated in three respective sections exploring each of the above-mentioned aspects.

The collected data can be considered representative of the perception of climate change effects on flood risk within urban contexts typical of Southern Italy. In this geographical area, urbanization has developed quite often with low attention to storm water management and urban planning in general; also, the seniors may have a quite low degree of education, given the predominantly agricultural vocation of the past economy in the area. Given these characteristics of the area, existing literature on the subject, and relative to other sites in the globe, may not be enough representative.

#### **2. Materials and Methods**

#### *2.1. Description of Survey Area*

The Simeto River basin (Figure 1) is located on the Southwest of Mount Etna, the largest active volcano in Europe, and is therefore characterized by quite unique natural features [44]. The basin extends in the territories of the provinces of Catania, Enna, and Messina, with a surface that measures approximately 4030 km2. The SRV is an area located along the central stretch of the Simeto River, which is the main river in Sicily, a few kilometers west of the Catania Metropolitan Area. Approximately 150,000 people live in the SRV area, distributed in 10 medium-small towns: the largest community is the city of Paternò with 50,000 residents, while the smallest is Ragalna with around 4000 [45]. In the last two decades, part of this community has been involved in participatory actions for the sustainable development of the area. In particular, thanks to the cooperation between local groups of citizens, organized in an association named Participatory Presidium of the Simeto River Agreement (PSRA) [46], local administration bodies and the University of Catania, in 2015 the municipalities of Paternò, Ragalna, S.M. di Licodia, Motta Sant'Anastasia, Belpasso, Biancavilla, Adrano, Centuripe, Troina, and Regalbuto, for a total of about 100,000 inhabitants, the PSRA and the University of Catania have signed the Simeto River Agreement (SRA), a river contract aiming at encouraging local development through participatory approaches (Figure 2). Figure 2 shows the location of the municipalities involved in the SRA along with the location of Catania, where the University of Catania is based, and where the present survey was also administered.

**Figure 1.** Location of the Simeto River basin on the east of Sicily (Italy).

**Figure 2.** Location of the municipalities involved in the Simeto River Agreement, plus the city of Catania.

The pluviometric regime in the Simeto River basin is characterized by maximum average values in the month of December and, progressively smaller, in the months of January, November, and October and the minimum average values in July or in August. The Simeto River basin, particularly in the central area at higher elevations, is subject to heavy rainfall events in autumn and spring [47]. With the increase of urban sprawl, impervious surfaces replaced the more permeable ancient streets, small retention areas have been covered, and new roads interrupted the hillslopes or new constructions have been introduced. This intensive urbanization has not been accompanied by adequate retrofitting for urban flood control. In the case of the municipalities on the slopes of Etna, the situation is further complicated by the need for an inter-municipal view of stormwater management, which is seldom fostered. The development of commercial, industrial, and urbanization services along the road axes realized a real urbanized continuum. It follows that this area is particularly vulnerable to changes induced by geomorphological and hydrogeological processes, which may exacerbate if solutions are not properly implemented. The current Basin Plan technical documentation quantifies the hazard and risk related to geo-hydrological hazards for the municipalities of the Simeto Valley. A summary of the figures for hydraulic and geo-hydrological hazard is shown in Tables 1 and 2. These data can be an element of comparison with the results of the survey, i.e., to see how risk awareness of the population corresponds to the expert knowledge of flooding hazard in the area. It is worthwhile to mention that, in such technical documentation, geo-hydrological risk is defined as the risk connected to the instability of the slopes, due to particular geological and geomorphological processes, while the hydraulic risk is linked to large river flooding following particular environmental, atmospheric, or meteorological and climatic conditions affecting rainwater and their hydrological cycle, with possible consequences on the safety of the population and on the safeguard of services and activities. As shown in the table of geomorphological hazard (Table 1), the municipalities with the highest surface area at risk are Centuripe, Regalbuto, and Troina, while the ones with the highest surface at hydraulic risk (Table 2) are Catania, Paternò, and Belpasso.


**Table 1.** Extension of the areas with different levels of geomorphological hazard, as quantified by the plan for the Simeto River basin, P4 indicates the highest level of hazard, P1 the lowest [47].

**Table 2.** Extension of the areas at different levels of hydraulic hazard for the Simeto River basin, P3 indicates the highest level of hazard, P1 the lowest [47].


In addition to these figures, it should be mentioned that the SRV has been repeatedly hit in recent years by intense pluvial flooding events, caused by heavy rain in combination with an overwhelmed drainage system. These events proved that it is important to develop strategies with different time horizons and priorities for management alternatives to mitigate pluvial flooding risk.

The city of Paternò, which has about 50,000 residents, has experienced several times pluvial flooding episodes that affected the entire city. For instance, in the fall of 2009 and subsequently, in November 2011, March 2013, and August 2015, this city has been hit by intense rainfall and the city drainage system proved insufficient, with the consequence of flooding of the roadways and damages to public and private buildings. More recently, in October 2018, a flood caused a dangerous situation near the riverbed of the Simeto River, where some houses that fall along the banks had already been invaded by water and mud. The greatest damages recorded were those caused by the overflow of the Simeto River. The waters of the river invaded the Catania-Siracusa Highway, which was temporarily closed. Another event occurred in October 2019, when Paternò and the surrounding cities were hit by a heavy storm. The situation appeared critical and the peripheral roads were invaded by water and mud, a person was trapped in an underpass. Another person was rescued in extremis by a truck driver after his car was left at the mercy of the river of mud with no possibility of movement. These episodes are just a few of the many signs that reveal the need for a better understanding of the potential risks for people's lives during intense rainfall and consequent flooding. Figure 3 shows some images of floods of recent years in the cities of Paternò and Catania.

**Figure 3.** Images of the floods of recent years: (**a**) street of Paternò during the flood of August 2015, (**b**) square of Paternò during the flood of March 2013, (**c**) Via Etnea of Catania during the flood of October 2018, (**d**) Piazza Università of Catania during the flood of October 2018.

It is important to specify that insurance against flood damages is not so common among citizens. The Ministry of infrastructure and transport and the Ministry of the Environment and Land and Sea Protection, as well as local departments, allocate funds for hard and soft measures against floods and other natural disasters. State and Regional special laws are emanated in case of catastrophic natural disasters for compensating flood damages and for reconstruction of damaged areas.

#### *2.2. Study Design*

The design of the survey considered some other works, both Italian and foreign, which have a similar structure. For example, the municipality of Ferrara (Italy) in 2010 conducted a study based on nine multiple-choice questions to better understand knowledge, sensitivity, and interest in climate change through the population [48]. The Joint Disaster Management Risk Assessment and Preparedness in the Danube Macro-region project [49] conducted a study to evaluate climate change perception, submitting to citizens multiple-choice questions, as in our case, about the involvement by the media on the treatment of the topic, the perception of climate change compared to past decades (especially for the adult population) and the actual derived risks, including extreme precipitation events and floods. A study by Yale University estimates U.S. climate change beliefs, risk perceptions, and policy preferences at State and local scale using the Yale Climate Opinion Maps based on 2018 data [50]. This survey, with its about 20 questions with Likert scale [51], tried to investigate the opinions of the community regarding climate change and the risks deriving from it.

In 2017, the European Commission published the special Eurobarometer 459, with the result of a large-scale survey proposed in some European countries. The key topic was, again, the perception of climate change, but with a focus on the responsibilities of national governments [52].

The survey here in question, reported entirely in the Appendix A, consisted of 10 questions, some of them structured with answers requiring a numerical value, following the Likert scale [51]. The questions were formulated independently against each other and their number was reduced to the minimum in order to keep it less tedious for respondents, in order to reach a high number of participants.

As already mentioned, the survey is divided into three sections. In detail, the first part of the survey recalled recent episodes of severe flooding occurred in the Simeto Valley in the autumn of 2018. We asked if such events were related to climate change, or if they could be considered frequent events during the fall season or else if they were isolated phenomena. Subsequently, we asked how often they heard about climate change and through which channels. The central part of the questionnaire started by analyzing the day-life experience of citizens, by asking if they pass or live close to places frequently flooded during extreme rain events. Then we asked, using a Likert scale, how worried they feel about weather alerts, to understand how much confidence the citizen have in the Civil Protection and local authorities, which are responsible for issuing such alerts. Finally, we investigated their individual preparedness, i.e., their tendency to behave correctly during urban flooding, asking them what they would do in three distinct possible scenarios: they are at work or at school, they have to go through an underpass or they have to pass a bridge.

The last part of the questionnaire concerned the community's willingness to adapt to climate change, as a further measure of long-term preparedness. First, we asked about the best practices for adapting to climate change according to citizens, to investigate whether they really knew the meaning of this type of practice. Finally, we investigated how much they would be willing to spend to implement measures for climate change adaptation. In this sense, they were asked whether they were willing to accept a municipal expense for the purpose and whether they were willing to invest in new adaptation works on their private properties. This last part has been automatically submitted only to adults (over 19 years old), as for the children these questions are of difficult understanding or not relevant. The survey had anonymous answers, but prior to the 10 illustrated questions, the participants had to fill some general information on their age, gender, main occupation, education level, and city of residence in order to socio-geographically characterize the answers.

It should be pointed out that this survey has been carried out in a local context where various community involvement actions are already active. As mentioned above, recently part of this community has been involved in participatory actions for the sustainable development of the area, therefore some citizens are already somehow sensible to some of the topics of the survey. In a context such as this, the present questionnaire aims to serve not only as a statistical and investigative tool but also represents a training opportunity for citizens, bringing their attention to its topics, as well as the possibility of encouraging and strengthening community involvement within the SRA.

#### *2.3. Distribution of the Survey and Sample Characterization*

The survey was published and distributed mainly electronically through the webplatform EU Survey (https://ec.europa.eu/eusurvey, accessed on 15 February 2021), for a period of about three months and was advertised through the social channels of the LIFE SimetoRES Project IT-LIFE17\_CCA\_IT\_000115, Simeto River Agreement, and the University of Catania social channels (Facebook, Twitter, institutional websites). Such distribution was supported by the active work of volunteers from the Participatory Presidium of the Simeto river agreement, the umbrella of volunteer organizations deeply involved in several aspects of the project. Instant messaging (mainly WhatsApp) was also effectively used, sharing the link to the questionnaire in chatting groups of local community associations, school (parents and classes), professional orders, and others. A paper hardcopy version of the survey was also distributed during some public events in order to involve even those that may have been reached by social media only marginally. The answers were 1143 in total, 1078 collected electronically, and 65 hardcopies formats, distributed per municipality as shown in Table 3, and by individuals' characteristics as illustrated in Figure 4. The percentage of women is slightly higher than the percentage of men, the age groups are adequately represented except for the group of children (younger than 14 years old) who are only about 1% of the respondents. Almost 38% of the participants are high school graduates and approximately one-third are university graduates. Most of the participants study or work, only 11% are unemployed, and just slightly more than 4% are retired.


**Table 3.** Number of responses received from each municipality and percentage of responses out of the total answers to the survey.

**Figure 4.** Social characterization of the participants to the survey in terms of (**a**) gender, (**b**) age, (**c**) education, (**d**) work.

#### **3. Results**

#### *3.1. Worry about Climate Change*

There has been lengthy debate in the scholarly community about whether individuals can "experience" climate change on a first-hand basis [38]. Some studies claim that global climate change is effectively invisible to laypeople, as climate change, by scientific definition, relies on statistical data compiled over long periods of time [53,54]. Ethnographic and survey results, however, have suggested that some members of the public believe that they have experienced climate change through seasonal changes, or living through extreme weather events [38,55,56].

In this case, in particular, around 84% of interviewees responded that the extreme rainfall events that hit Sicily in 2018 were mainly due to climate change. Only 8.7% of respondents believe that these phenomena have occurred as they are extreme events due to natural climate of the area. As a matter of fact, the study area has experienced even more severe events in the past, therefore the link with climate change is highly uncertain, so this question contributes by measuring the level of worry by the population. It is interesting to note that the likely correct interpretation (heavy rainfall events occur quite often in autumn, so there are quite normal in this season) is more frequent within the age group of over-60s, as the 20% of them answered so, while in the other age groups the percentage remains less than 10%. Additionally, rather a considerable percentage of school-age students (30.77%) are not able to decide whether such events are due to natural climate variability or to changed conditions, i.e., they are not able to identify a possible cause for this type of events (Figure 5).

**Figure 5.** Results for the question: 'During the autumn of 2018, Sicily was hit by heavy rains in both the eastern and western parts, what do you think these phenomena are due?' Answers classified according to different age groups.

Regarding the exposure to information on climate change, over 44% of participants answered that they hear about climate change "at least once a week" and almost 30% even "once a day" (Figure 6). This indicates that the population is quite interested and worried about climate change as it is discussed in usual conversations, within all age groups. Table 4 shows the different information sources through which the inhabitants declared to "hear about" climate change. For this question, multiple answers were allowed. The table shows that the most frequent source of information on climate change is newspapers, radio, and television (77.89%), followed by social media and the internet in general (66.53%).

**Table 4.** Sources from which population responded to hear about climate change. Respondents could select more than one answer (percentages do not sum up to 100% as multiple answers were accepted).


#### *3.2. Direct Experience of Urban Flooding and Risk Preparedness*

More than 62% of the respondents answered that they cross areas prone to flooding during heavy rainfall events. This could be related to the fact that the problem is diffused within a large area. Figure 7 shows the answers divided into the different municipalities. The chart shows that the municipalities where the higher number of respondents declared to cross floodable areas are Catania, Biancavilla, and Adrano. Instead, the less interested in floods are Centuripe, Troina, and Regalbuto, cities which are located at the top of mountain areas. However, even in these municipalities, more than 50% of participants stated that they cross dangerous areas during intense storms: this could is related to the fact that these cities have many commuters that move out of their town for work/school on a daily basis, for example, it is possible that many citizens need to go to Catania for work, study or other needs, which is the closest city with services. After this question, participants were asked to indicate their degree of concern during weather alerts. Table 5 shows that most respondents (around 45%) have a "medium" level of concern and only 32% have a high or very high level of concern (the sum of 23% and 9%). This happens probably because of the relatively large spatial and temporal uncertainty of the weather alerts in the region, which remains significant to a degree that may induce a partial distrust about them—a phenomenon also known as *cry wolf syndrome* [57]. In fact, in recent years, there have been several cases in which weather warnings have been issued without any rain occurring, other times there have been very intense rain events without there being any weather warnings: these situations contribute to confuse citizens, who lose confidence in the weather alert service.

**Figure 7.** Responses to question 'Do you cross areas that are likely to be flooded during a rain event?' The size of the indicator represents the quantity of responses coming from individual municipalities, while the color indicates the type of response.

**Table 5.** Level of concern during a weather alert.


Regarding risk preparedness, the charts in Figure 8 show the answers on the behavior during potentially dangerous scenarios in three different cases. In the first question, we asked how the citizens would behave in case of a storm if they were indoors at school, work or gym. The chart shows that almost 74% know the right behavior to take; in the second question, we asked what behavior they would have if they were in the situation to decide to cross an underpass, even in this case almost 74% of the interlocutors answered correctly; instead, the third question asked about their choice in case of crossing of a bridge during an exceptional rain event. In this case, only about 48% of participants gave the answer corresponding to the correct behavior. As it can be seen from the graph, 20% of people would not actually know how to behave and about 33% of participants would have risky behavior. It is also interesting to investigate the answers according to the different age groups (Figures 9–11). We note that young people are actually the least aware about what to do in the case of an extreme rain event. Only 15% of children (up to 14) and 35% of teenagers (from 15 to 19) answered correctly.

**Figure 8.** (**a**) Answers to the question: "What do you do if there is a storm and you are at work/school/gym?" (**b**) Answers to the question: "What do you do if there is a storm and you are in your car/scooter and you have to pass an underpass?" (**c**) Answers to the question: "What do you do if there is a storm and you are in your car/scooter and you have to pass a bridge?".

**Figure 9.** Responses to question 'What do you do if there is a storm and you are at work/school/gym?'.

**Figure 10.** Responses to question 'What do you do if there is a storm and you are in your car/scooter and you have to pass an underpass?'.


**Figure 11.** Responses to question 'What do you do if there is a storm and you are in your car/scooter and you have to pass a bridge?'.

Moreover, we asked if they feel personally responsible for flood prevention, and how much they think other public bodies are responsible for protection from the induced risk. The citizen had the possibility to assign a score based on the degree of assigned

responsibility in the case of flood event for the different bodies indicated. Using a Likert scale the responsibilities were divided into low, medium, or high. The result shows that only 35.5% of citizens consider themselves to have a responsibility in flood prevention, while almost 30% believe they have a very low responsibility. It also shows that there is a high tendency to attribute most of the responsibility to public bodies, in particular to the Central Government (Figure 12).

**Figure 12.** Answer to the question concerning the attribution of responsibility for the prevention of flood risk.

#### *3.3. Willingness to Adaptation*

The first question of this section asked the participants to identify the best practices for adapting to climate change, in order to investigate whether respondents know the meaning of adaptation and how it differs from the concept of mitigation. Knowledge of this difference is fundamental to the population to be a catalyst for the implementation of adaptation actions, as these are of different nature than the mitigation actions. In fact, the former does not focus on a reduction of greenhouse gas emissions, while the latter is mainly oriented to that scope, thus requiring totally different strategies.

The outcomes of the survey show that citizens are mostly confused about this point (Table 6). Almost 44% of the interviewees answered that waste sorting is an adaptation measure and over 58% indicated renewable energy production, while both should be mainly considered mitigation measures. Then, more direct questions on the willingness for adaptation were asked. In particular, participants were first asked if they would be favorable to an increase of investments in sustainable drainage infrastructures by their municipality. The answers have been represented in Figure 13, as a function of the age group. Overall, almost 80% of the answers indicated willingness to accept an increase in public costs if well justified; however, mainly adult groups (i.e., over 30 years old) seemed more favorable to this type of initiative. Then, the question was oriented to a more individual statement: citizens were asked whether while restructuring their own properties, they would be willing to increase their expenses to put in place sustainable drainage practices, such as increasing the surrounding pervious surfaces (Figure 14). Over 82% of young adults in the age between 31 and 45 years have responded to be willing to do that, while people aged less than 30 years seem to be the less willing to make such an investment.


**Table 6.** Responses to question 'Which of these are good practices for adaptation?'.

**Figure 13.** Answer to the question: "Your municipality is investing funds for the construction of a new parking and decides to spend 10% more for make it with pervious materials that allow stormwater retention and therefore reduce urban flooding. What do you think about that?".

**Figure 14.** Answer to question: "In building or renovating your home would you be willing to spend more to introduce more green areas and less asphalted surfaces to better adapt to climate change?".

#### **4. Discussion**

#### *4.1. Analysis of Direct Results*

In this section we firstly present an overall summary of the direct results of the survey, we briefly compare our results with those presented in related studies in the literature, and finally, we carry out some cross-analysis of the various factors explored with the survey, and in particular the possible links between the worry of population about climate change and how this may influence their preparedness.

Table 7 presents a short overview of the main direct results of the survey, which were presented in detail in the Results section. With "direct results" we mean those that can be derived from one single question, without analyzing possible relationships between the answers.


**Table 7.** Summary table with main direct results of the survey.

Our investigation indicated that most of the citizens are worried about climate change and confirmed that they are highly interested in the topic, as they follow information coming from multiple media streams and discuss it prevalently on a weekly (44%) or daily basis (30%). The predominant perception is that there is a link between floods in the last decade and climate change (84%). With reference to the direct experience of residents during heavy rain events and related urban flooding, most citizens agree that the urban areas of the SRV are prone to flooding, as many of them report to cross flooded streets. However, they are quite sceptical regarding the weather alerts, as they perceive them more as a problem in their daily activities rather than a protection of their safety. A significant percentage of the population is unaware of the basic rules for individual safety during a heavy rainfall event, as more than 1 out of 4 persons would have wrong behavior during urban flooding risky situations. Finally, it seems that there is a modest willingness of citizens to implement adaptation actions in their own municipality and real estate. Although it is not possible to know if citizens actually carry out works (public or private), the answers to the last questions reveal a certain desire of the population to accept new measures if it means adapting to climate change and thus improving safety.

#### *4.2. Comparison and European and National Studies*

We attempted to compare these direct results with those of other areas, as reported in recent similar studies, in order to find possible divergences, which we discuss in the following. For example, at the European scale, according to the 2017 Eurobarometer Report [52], it is clear that 74% of citizens actually consider climate change as a serious problem, while in our case over 83% of respondents believe that climate change is responsible for exceptional phenomena that cause serious problems and damage, showing potentially a higher degree of concern. As regards responsibilities, in Europe, only 43% of the responsibility for preventing the risks associated with climate change is attributed to the government, while in the SRV the percentage of citizens of the SRV who hold the government responsible is higher than 77.4%. On the other hand, European citizens that feel personally responsible for the prevention of the flood risk are only 22% against the 35%

of our respondents. This in general indicates that the population agrees on the fact that the local and national administrators do not take sufficient actions for protection of the territory against urban flooding. At a national level, the only survey deemed to have comparable questions with ours is the one conducted for the Municipality of Ferrara [48], in the north of Italy, in which however only 164 questionnaires were analyzed (approximately 0.1% of the population). The analysis found that about 61% of citizens perceive the evidence of climate change (vs. 83% in our case, based on question 1) and about 58.5% believe that it is very important to take actions to mitigate the impacts of climate change (vs. 79.9% for the SRV). In the Municipality of Ferrara, 20% of the responsibility for preventing the risks associated with climate change is attributed to the State and over 55% to the Municipality, while the citizens of the SRV hold the State the most responsible (77.4%). The percentage that feels directly involved and responsible for risk prevention is more or less the same in the two areas, around 35%. Citizens of Ferrara that are moderately willing to invest in adaptation measures are about 37.5%, while 37% are very willing. Regarding SRV citizens, more than 77% of them are very willing to personally support the costs for adaptation measures.

Of course, the presented comparison is subject to some limitations mainly due to the fact that not the exact questions and methodologies have been done and applied. Nevertheless, the differences are quite high and potentially significant also taking into account the possible influence of the above-mentioned limitation. Hence the comparison confirms the relevance of investigating the SRV, as it presents specific features that other studies do not allow to infer.

#### *4.3. Cross-Analysis: Link between Worry about Climate Change and Urban Flooding Preparedness*

In many parts of the industrially-developed world, efforts in the media and in schools are mainly oriented to build awareness of the climate change issue, as also stimulated by several activist movements, such as Extinction Rebellion (https://extinctionrebellion.uk/ the-truth/, accessed on 15 February 2021) and Fridays for Future (https://fridaysforfuture. org/, accessed on 15 February 2021), whose real impacts and advantages are under study by several scholars [58–60]. Here, we wanted to explore, the possible linkages between building an awareness of the risks related to climate change and the advantages in terms of a possible increase in the awareness of related urban flooding risk and the willingness to adaptation. This is allowed by the data collected in our survey by cross-analysis of part 2 (direct experience of urban flooding and risk awareness) and 3 (willingness to adaptation) vs. part 1 (concern of climate change and connection with urban flooding). To investigate these aspects, two contingency matrices have been derived linking respectively relevant questions of part 1 with part 2 (Table 8) and part 1 with part 3 (Table 9) of the survey. This approach is similar to that applied in the case of prediction problems where the use of the contingency matrix (also termed as confusion matrix) allows the understanding of the performance of the predictor in terms of Receiver Operating Characteristics (ROC) [61,62]. In particular, the following assumptions were made in computing the quantities in Tables 8 and 9:

	- - A partial score of 1 was assigned when the interviewee answered "These are phenomena due to climatic changes taking place on the planet" to question 1, a score of 0 otherwise
	- - A partial score of 1 for who hears about climate change at least once a day, 0 otherwise
	- - The degree was classified as "higher" if total score (sum first and second item) was at least 1, "lower" otherwise
	- - A partial score of 1 was assigned to each answer corresponding to correct behavior (questions 6a–c), and 0 to a wrong behavior
	- - A "likely" correct behavior was assigned to individuals that had a total score of 2 or more, while it was deemed "unlikely" otherwise
	- - A partial score equal to 1 was attributed to answers "It's well-spent money, the Municipality has done a good thing" (question 9) and "Absolutely yes" (question 10)
	- - A "higher" willingness level to individuals that had a total score of 1 or more, "lower" otherwise

**Table 8.** Contingency table for exploring link between concern for climate change and the possible correct behavior of individuals during urban flooding.


**Table 9.** Contingency table for exploring link between concern for climate change and the possible willingness to invest in adaptation actions.


Once the categorization has been done and entries of the contingency tables have been counted, conditional frequencies have been computed to test whether the degree of interest and concern for climate change is related to a variation of the likelihood of correct behavior during urban flooding events and a higher willingness to invest in adaptation. In particular, to test whether there is a significant variation the following conditional frequencies have been computed: frequency that a person behaves correctly during urban floods (is willing to invest in adaptation actions) given that he is highly concerned about climate change, and frequency that a person behaves correctly during urban floods (is willing to invest in adaptation actions) given that he is lowly concerned about climate change. These two conditional frequencies correspond to *A*/(*A* + *B*) and *C*/(*C* + *D*).

$$H = A/(A+B) - C/(C+D) \tag{1}$$

The difference provides an indication whether the conditioning factor is important or not: if *H* is significantly greater than zero the concern about climate change positively affects behavior during floods (increases willingness to invest in adaptation actions), if is significantly less than zero than the influence is negative, if *H* is approximately zero then there is no influence. We consider a threshold of |*H*| = 0.2 for significance. In the context of ROC analysis, *H* is also termed as true skill statistic or Hanssen–Kuipers discriminant [63–65]. As can be derived from Tables 8 and 9, the difference in both cases is 0.05, i.e., non-significant. This means that to be concerned by climate change does not give any advantage in resilience, i.e., does not induce a better behavior against the climaterelated hazard of urban flooding, nor on the willingness to invest in a sustainable solution for adaptation to climate change increases. In other words, people are not as willing to take actions as they are to be concerned when it comes to climate change.

#### **5. Conclusions**

The results of a survey exploring worry about climate change and its possible relation with the behavior during urban floods and the willingness to invest in adaptation actions have been presented, relatively to the Simeto River Valley area in Sicily. The data collection that was made is quite relevant with respect to other studies, as here more than 1000 persons were interviewed, while it is difficult to find regional studies with more than a few hundreds of participants involved. The simplicity of the survey was a crucial factor for collecting such a high number of answers, but, on the other hand, has not undermined the possibility to arrive at important conclusions about the issues explored. The overall picture deriving from the present analysis highlights how there is a high concern for the possible impacts of climate change, specifically in connection to urban flooding. The climate change issue entered in almost every-day conversations by the population. However, this high level of concern does not correspond to a comparable level of knowledge of the correct behavior during climate-related extreme events—specifically urban flooding—and the willingness to invest in adaptation measures. In fact, the population tends to attribute increasingly intense events to climate change but does not know the correct behavior to take during the emergencies, does not correctly attribute the responsibility for flood-caused damage, and does not trust authorities that are in charge of human safety. The crossanalysis that we carried out, shows that there is no gain for these two resilience factors associated with a higher degree of concern about climate change. Overall, the outcomes of the survey suggest that the information that is conveyed by the media and taught in schools is mainly oriented to increase the worry about climate change and that this is not significantly useful for an increase in the resilience of the populations, i.e., specifically a higher risk awareness during urban flooding events and of the importance of investment in sustainable drainage practices. Hence, greater efforts should be spent through media and education to build a greater risk preparedness rather than prevalently a greater worry about climate change.

**Author Contributions:** Conceptualization, all authors; Formal analysis, P.N. and D.J.P.; Funding acquisition, A.C., R.E.M. and D.J.P.; Investigation, all authors; Methodology, all authors; Project administration, A.C. and R.E.M.; Resources, A.C. and R.E.M.; Supervision, D.J.P., A.C. and R.E.M.; Visualization, P.N. and D.J.P.; Writing—original draft, P.N. and D.J.P.; Writing—review & editing, all authors. All authors have read and agreed to the published version of the manuscript.

**Funding:** This work has been partly funded by the EU project LIFE SimetoRES (IT-LIFE17\_CCA\_IT\_000115), whose partners are the municipalities of Paternò, Ragalna, Santa Maria di Licodia and the Department of Civil and Environmental Engineering of the University of Catania.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Data are available by request to the authors.

**Acknowledgments:** The Participatory Presidium of the Simeto River Agreement is strongly acknowledged for its active support in all the communication activities of the project, and in the dissemination and collection of the questionnaires. The authors thank Laura Saija for the fruitful discussions and Gabriele Gugliuzzo for the collaboration in organizing the results. This work is in partial fulfilment of the Ph.D. activities of P.N.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **Appendix A**

The survey consists of a combination of 10 questions, including some multiple choice and others using the Likert scale (1932), preceded by 5 questions related to the characterization of the sample. The questions were formulated to be independent of each other and each of them is aimed at extrapolating precise information. The survey was administered in Italian language. Below we show the questions translated in English.

#### **Sample characterization:** Gender


How old are you?


Education


What is your current occupation?


Where do you live?


#### **Perception of climate change:**

Question No. 1

During the autumn of 2018, Sicily was hit by heavy rains in both the eastern and western parts, what do you think these phenomena are due?


Question No. 2 In the last years, how often have you heard about climate change?


Question No. 3

Where did you hear about climate change? (More options can be selected)


**Perception of flood events, behaviour during weather alerts and related responsibilities:**

Question No. 4

Do you cross areas that are likely to be flooded during a rain event?


Question No. 5

The news talks about a serious weather alert for tomorrow, how do you feel? Indicate your degree of worry (1 means "very little", 5 means "very much")


Question No. 6 In the event of a flood what do you do if:

a. you are at work/school/gym


b. you are in your car/scooter and you have to pass an underpass?


c. you are in your car/scooter and you have to pass a bridge?


Question No. 7

Indicates the degree of responsibility for the prevention of flood risk of the following figures where 1 means very little and very much 5.

The citizens


The Mayor and the Municipality


#### Civil Protection and Firefighters


#### The State


#### **Willingness to adapt to climate change**

Question No. 8

What are good practices for adaptation? (Choose max 3 options)


Question No. 9

Your municipality is investing funds for the construction of a new parking and decides to spend 10% more for make it with pervious materials that allow stormwater retention and therefore reduce urban flooding. What do you think about that?

	- Question No. 10

In building or renovating your home would you be willing to spend more to introduce more green areas and less asphalted surfaces to better adapt to climate change?


#### **References**


### *Article* **The Flash Floods Risk in the Local Spatial Planning (Case Study: Lublin Upland, E Poland)**

**Bogusława Baran-Zgłobicka 1, Dominika Godziszewska <sup>2</sup> and Wojciech Zgłobicki 2,\***


**Abstract:** Flash floods pose a significant threat to humans but the state of our knowledge on the occurrence and related risk of such phenomena is insufficient. At the same time, many climate change models predict that extreme rainfall events will occur more and more frequently. Identifying areas susceptible to flash floods is more complicated that in the case of floods occurring in the valley bottoms of large rivers. Flood risk maps in Poland have not been developed for small catchments. The study objective was to assess whether the threat related to flash floods is taken into account in the spatial planning system of municipalities. Studies were conducted in the Lublin Upland, E Poland (an area of about 7200 km2). A preliminary assessment of susceptibility of 369 catchments to flash floods was carried out in a GIS environment using multi criteria analysis. The susceptible catchments cover about 30% of the area. Existing planning documents, flood hazard and flood risk maps were analyzed for municipalities located in the catchments with highest susceptibility to this phenomenon. Our results show that flash flood risk is usually not recognized at the level of local governments even when it is significant. Local planning documents do not take into account the existence of this threat.

**Keywords:** floods; GIS; natural hazards; risk management; spatial management

#### **1. Introduction**

Flash floods are among natural hazards to which more and more attention is devoted due to their social and economic impact [1–6]. The term is applied to a rapid rise in water level, characterized by short duration and high intensity of maximum flows posing a threat to people [7,8]. According to Ostrowski et al. (2012) [9], a flash flood is a flood with a high water-volume lasting for a short time and occurring after a sudden, intensive rainfall (usually a rainstorm). Initially, the term applied to phenomena related to floods resulting from the breaking of reservoir dams. Flash floods pose a significant threat to humans because they are triggered by torrential rainfall that can occur almost anywhere [1,10,11]. It is estimated that 40% of flood victims in Europe between 1950 and 2006 suffered because of flash floods [12]. At the same time, some climate change models predict that such extreme rainfall events will occur more and more frequently [13], hence the risk posed by flash floods is probably going to increase. Nonetheless, the problem requires further study [14,15].

In agricultural areas, intensive surface runoff after heavy rainfall causes strong gully erosion that leads to the destruction of crops and roads [16,17]. The accumulated material silts up fields, roads and farms. The flood wave rapidly forming in the valley bottoms is a threat to human health and life and causes considerable material losses. Such floods pose a significant problem to local governments as they usually have to deal with repairing the flood damage on their own [7]. Typical flash floods in Poland affect catchments covering less than 40 km2. They result from rainfall usually lasting up to two hours and having an

**Citation:** Baran-Zgłobicka, B.; Godziszewska, D.; Zgłobicki, W. The Flash Floods Risk in the Local Spatial Planning (Case Study: Lublin Upland, E Poland). *Resources* **2021**, *10*, 14. https://doi.org/10.3390/ resources10020014

Academic Editors: Brunella Bonaccorso and David J. Peres

Received: 28 December 2020 Accepted: 8 February 2021 Published: 11 February 2021

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

intensity of 20–80 mm h<sup>−</sup>1. Phenomena of this type occur most often in July and May and June [18].

Local flash floods occur in Poland and in other parts of Europe mainly in upland and mountain areas. Their spatial distribution is determined by two factors—climate and topographic conditions [1,2,19]. High slope gradients, higher density of the river network and shallower soil cover quickly lead to the development of intensive surface runoff [7,20]. The state of our knowledge on the occurrence, determinants, and course of such phenomena is insufficient [21]. Flash floods can thus occur in unexpected and totally unprepared locations (Figure 1). Identifying areas vulnerable to flash floods is more complicated that in the case of floods occurring in the valley bottoms of large rivers. Rapid runoff and flooding can occur in areas practically devoid of permanent drainage and not covered by the network of standard meteorological and hydrological measurements.

**Figure 1.** Effects of a flash flood in Fajsławice municipality (June 2016) (source http://www.krasnostawska. pl/siedliska-znowu-pod-woda/; accessed on 20 December 2020).

Studies on flash floods in Poland focus mainly on mountain areas. Based on the analysis of selected characteristics of the natural environment of small catchments of the Foothills (Carpathian Mountains), Bryndal (2011) [22] identified areas susceptible to the occurrence of such phenomena. Ostrowski et al. (2012) [9] prepared a catalogue of flash floods in the years 1971–2010, assessed the dynamics, cyclic nature and frequency of these phenomena, and identified regions at particular risk of flooding. Several studies describe the hydrological and geomorphological effects of these phenomena [14,23–25].

The identification of catchments at risk of flash floods is most frequently carried out by analyzing a number of various criteria by means of GIS (geographic information systems) [26–30]. These studies encompass individual cities [31] or entire countries [30,32]. In the case of studies concerning small areas, detailed data and advanced models difficult to use for larger areas are often employed. Studies encompassing entire countries are usually based on data and maps in small scales. Particular attention is devoted to this threat in urban areas, especially those with numerous underground structures, such as the metro (subway) [33,34].

The appropriate use of spatial resources is one of the ways for humanity to adapt to the expected climate changes [35,36]. Assessing the inclusion of areas exposed to such hazards in the spatial planning process was an important aspect of the conducted research [7,37]. This is particularly important in the context of the present-day changes in land cover and development of the settlement network taking place. Spatial planning is regarded as one of

the main instruments for managing adaptation to climate change and managing the effects of climate change in the spatial context [35,38,39], also with regard to limiting the negative effects of floods [40–42]. Flood risk management is a matter of cross-sector collaboration controlled, at different levels of territorial division of countries, by various institutions and state administration bodies [43]. The full coordination between government bodies and entities competent in risk management, i.e., protection of the population, spatial planning and sectoral programs (e.g., in the field of water management) is a systemic challenge not only in Poland. For the already developed areas in the valleys of smaller rivers, risk reduction can be achieved by educating the residents, preparing warning systems and effective crisis response plans and protective measures for individual buildings [44]. Another matter is the spatial chaos and crisis of spatial planning, which constitute a major obstacle to the sustainable development of the country [45].

The study objective was to assess to what extent the threat related to the potential risk of flash floods is taken into account in the spatial planning system of municipalities. The first step was the identification of catchments susceptible to flash floods in the agricultural area of the Lublin Upland (E Poland). Results of the assessment allow one to identify areas (catchments and municipalities) exposed to a potentially greater flash flood hazard if heavy rainfall occurs (higher hazard). Then, planning documents and existing flood maps were analyzed in terms of identifying the flash flood risk. For the valleys of large and medium rivers, flood hazard maps and flood risk maps are developed in Poland in accordance with the European Flood Directive. In the case of smaller valleys, however, areas at risk of flash floods were not prepared [7,16]. The results of studies on the inclusion of phenomena such as flash floods in the spatial planning system have not been published in Poland so far. This problem has not been more widely discussed in international literature either.

#### **2. Materials and Methods**

#### *2.1. Study Area*

The Lublin Upland is located in the south-east of Poland (Figure 2). The region, covering 7200 km2, is divided into nine physical geographical regions In terms of the administrative division, the Lublin Upland is located in Lubelskie Province. The substrate of the Lublin Upland consists of lithologically varied Cretaceous and Paleogene carbonate rocks. They are overlain by tertiary limestone and various Pleistocene deposits: till, sand, gravel and periglacial loess. The Lublin Upland reaches the highest elevation in its central and eastern parts (up to 300 m a.s.l.), from where it descends to the north-east and north-west to an elevation of about 200 m a.s.l. The plate structure of the Cretaceous and Paleogene bedrock is reflected in land relief—vast, flat top plateaus are common in the area. The general outline of the area is influenced by the properties of Upper Cretaceous rocks that form area of the hilly type. The diverse land relief is reflected in the names of the mesoregions: Małopolska Vistula Gap, Nał ˛eczów Plateau, Bełzyce Plateau, Chodel ˙ Basin, Urz ˛edów Elevation, Swidnik Plateau, Giełczew Elevation, Grabowiec Elevation and ´ Zamo´s´c Depression. Diversified landscapes may be found here: monotonous plateaus, hilly areas dissected by deep and narrow river valleys, residual hills, dense gully networks, escarpments, karst depressions and sandy planes with dunes.

The annual precipitation is about 550–600 mm, the mean annual air temperatures range from 7.0 to 7.6 ◦C and the mean specific runoff rate is about 4.0 dm3/s·km2. Precipitation in this region occurs most often in the summer season, frequently in the form of downpours and storms. The period of intensive precipitation lasts about 210 days, i.e., longer than in other regions of Poland [46].

The rivers of the Lublin Upland are small. The river network in the southern part of the Upland is sparse while it is a bit denser in the northern part. The main river flowing across the Lublin Upland is the Wieprz; it also drains the greatest amount of water, the mean flow at its estuary being about 17 m3/s. The Bystrzyca, the biggest tributary of the Wieprz, carries about 5 m3/s while the flow of other rivers in the region does not exceed 2 m3/s. Groundwaters occur in Cretaceous, Tertiary and Quaternary formations. The main aquifer is mainly in the Upper Cretaceous deposits [46]. Outside of river valleys, groundwaters occur deep (30–50 m and more) below the ground surface.

**Figure 2.** Location and topography of the Lublin Upland; 1—the main rivers, 2—boundary of the Lublin Upland.

The Lublin Upland is a region where torrential rains, heavy rains or hail storms occur relatively frequently. The amount of rainfall reaches about 20–30 mm each time, and in some cases as much as 100 mm. The duration of such rainfall events can be short: from a few to several dozen minutes. These phenomena result in intensive surface runoff that leads to rapid rises in water levels. These phenomena occur locally, often affecting areas between ten to several dozen square kilometers, with 70% of the precipitation occurring in June and July. In the 1951–2000 period, between 10 and 20 rainfall events with a daily volume of more than 100 mm were recorded. The best-known events from that period included the heavy rains in Piaski Szlacheckie in 1956, in Dzierzkowice in 1969 and in Kazimierz Dolny in 1981 [14].

The Lublin Upland is a typically agricultural region where arable land usually covers 70–80% of the area of the individual counties. The population density, ranging from 70 to 90 persons per km2, is slightly lower than the national average for Poland. A characteristic feature of the region is the occurrence of numerous family farm holdings with an average area of about 5 ha. Despite such a high fragmentation of production, the Lublin Upland is an important area of agricultural production in Poland due to the presence of fertile soils (Cambisols and Luvisols) [47]. Recent years, however, have seen a decrease in the agriculturally used areas resulting from the socioeconomic changes occurring here [48].

#### *2.2. Local Spatial Planning in Poland in Relation to Flood Risk Management*

A flood is a natural disaster (Act of 18 April 2002 on a State of Natural Disaster) [49]. Minimizing flood risk, ensuring safety during its occurrence and removing the effects of flooding requires the cooperation of state and local government administration with various institutions. It is also necessary to ensure a coherent formal and legal system concerning flood control, water management, spatial planning and crisis management. At the local level, it is the municipality's own responsibility to ensure "public order and safety of citizens as well as fire and flood protection, including the equipment and maintenance of a municipal flood protection warehouse" (article 7 § 1 (14) of the Act of 8 March 1999 on municipal government [50]. Pursuant to the Crisis Management Act of 26 April 2007 [51], the basic crisis management instrument of a planning character is the National Crisis Management Plan along with the provincial, county and municipal plans [52–54].

Spatial planning is a key instrument for the appropriate and rational design of spatial development. In Poland, the legal basis for this process is provided by the Act of 27 March 2003 on Spatial Planning and Development [55] that defines (article 1 § 1) "the scope and modes of procedure in land use designation for specific purposes and establishing the rules of land development, with spatial order and sustainable development regarded as the basis for these actions".

The local level of spatial planning that encompasses a spatial development conditions and directions study for a municipality ("study") and a local spatial development plan ("local plan") is the most important from the point of view of flood hazard management. A study is an act of internal management and cannot be the basis for administrative decisions. Its preparation is obligatory for the entire area of a municipality (town). A local plan, on the other hand, is an act of local law and, with certain exceptions, it is not obligatory. It can be prepared for an entire municipality and an individual plot of land. The provisions of a local plan must conform to the provisions of the study. In the absence of a local plan to determine the development requirements, a decision on development conditions and land use is issued [56,57].

The Act on Spatial Planning and Development [53] indicates the minimum scope of problems included in planning studies. A study should take into account conditions resulting from, inter alia, "the threat to the safety of people and their property" and, in relation to water "flood control requirements" (art. 10 § 1 of the Act on Spatial Planning and Spatial Development). A study should specify, among others, "areas particularly exposed to flood risk" (art. 10 § 2). A local plan must specify (art. 15 § 2) "the boundaries and ways of developing [...] areas particularly exposed to flood risk" and "detailed area development conditions and use restrictions, including the prohibition of building development".

In 2011 the provisions of the European Flood Directive were implemented (Directive 2007/60/EC of the European Parliament and of the Council) [58] in Polish law whereby spatial planning has been very strongly integrated into the process of reducing the negative effects of floods. The identification of the flood hazard is now formally regulated by the Water Law Act of 20 July 2017 [59], which makes Wody Polskie (State Water Management Company) and state and local government administration bodies responsible for flood control (protection) [60–62]. This protection is provided "while taking into account flood hazard maps, flood risk maps and flood risk management plans". Flood risk management includes, "in particular, prevention, protection, preparedness and responding when flood occurs, dealing with the effects of floods, restoration and drawing conclusions in order to reduce the potential adverse effects of floods on human health, the environment, cultural heritage and economic activity." (art. 163).

According to the European Flood Directive flood hazard maps (FHMs) and flood risk maps (FRMs) are drawn up for areas identified in the preliminary flood risk assessment. The purpose of preparing this preliminary flood risk assessment is to identify areas at risk of flooding, those with a significant flood risk or with a high probability of a high flood risk. The first assessment was carried out in the period 2010–2015 as part of an EU-funded project—the IT System for the Protection of the Country against Extreme Hazards (ISOK), which provides access to, among others, flood hazard maps and flood risk maps [63]. The final versions of flood hazard maps and flood risk maps were submitted to local government units in April 2015. Eventually, after protests of local governments (especially of cities), which often questioned the flood water extent presented on the maps and did not want to bear the high costs of changes in planning documents, optionality was introduced (art. 88f § 5, 6 of the Water Law Act of 2001, [64]). In 2016, a review and updating of the preliminary flood risk assessment was begun.

#### *2.3. Methods*

The assessment of the susceptibility of catchments to flash floods was divided into five steps: (a) identifying the characteristics of the catchment environment influencing this phenomenon; (b) collecting the necessary spatial data; (c) spatial analysis of the parameters; (d) quantifying the individual characteristics and (e) carrying out a synthetic assessment of susceptibility (Figure 3).

The fundamental part of the study consisted of the analysis of the existing planning documents for local government units located within the catchments with high susceptibility to flash floods. It was assessed whether this threat is recognized in these documents and reflected in spatial planning. It was also examined whether they are covered by the flood risk maps and flood hazard maps prepared as part of the implementation of the EU Flood Directive. Twelve studies (spatial development conditions and directions study for a municipality) and over 60 local plans (spatial development plans) or their changes were analyzed (Figure 3).

**Figure 3.** Scheme of research procedure.

Based on the analysis of the available literature on the determinants of the catchments' susceptibility to flash floods, it was found that, in the case of a study area of more than 7200 km2 (369 catchments), it would be advisable to use the following catchment characteristics: (A) catchment area; (B) circularity index; (C) mean catchment gradient; (D) density of the river network; (E) mean length of first-order watercourses; (F) forest cover; (G) built-up areas and (H) road density. A study prepared by Bryndal (2011) [20] for Carpathian catchments proved to be particularly valuable. In the study, he carried out a detailed analysis of catchment parameters influencing their susceptibility to rapid rises in water levels.

The catchment area is a significant parameter because flash floods usually occur in small catchments, covering from a dozen or so to 40 km<sup>2</sup> [9,20]. Therefore, the following rule was adopted: the smaller the area of a catchment, the greater its susceptibility to the occurrence of flash floods. The shape of a catchment (expressed by the circularity index) is important from the perspective of the speed of water supply to the watercourses. The higher the value of the index—and the shape of a catchment closer to a circle—the smaller the risk. With a more circular shape, the supply of water to the primary valley is more spread over time. The higher the slope gradients, the faster the formation of runoff occurs [17]. The formation of a flood wave is also more likely when the density of a permanent drainage network is greater and the length of first-order watercourses is smaller. The agricultural use of an area results in a quick formation of surface runoff. Thus, the susceptibility of a catchment to flash floods decreases with increased forest cover. On the other hand, a greater proportion of built-up areas (smaller infiltration) and roads (accelerated runoff) increases the flash flood hazard [65].

Land relief analysis was based on a digital terrain model with a spatial resolution of 30 m (SRTM). Data were sourced from the USGS Earth Explorer website [66]. Fourteen scenes connected with each other were used to obtain coverage of the entire area of the Lublin Upland. Watercourses in the form of the vector layer were obtained from the website of the Head Office of Geodesy and Cartography (GUGiK) [67]. The study used a layer containing the boundaries of catchments with permanent drainage. It was obtained from the resources of the Faculty of Earth Sciences and Spatial Management, UMCS. The study also used land cover vector data prepared as part of the CORINE Land Cover 2018 project. They were obtained from the resources of the Copernicus Land Monitoring Service [68]. The study used data related to built-up areas and forests. The road network (all roads) in the vector Esri shapefile format was generated from the OpenStreetMap [69] using the QuickOSM plugin in QGIS 3.4.4 software. All the analyses were carried out in ArcMap version 10.2.1. They were primarily based on the creation of maps presenting the spatial variation of the individual parameters and the susceptibility assessment results.

Digital maps were prepared showing the diversity of parameters within the catchments under study. Then the susceptibility of catchments was quantified according to the selected assessment criteria. For each catchment, eight parameters were rated separately on a 6-point scale. Varied weights of criteria, proposed by authors, were used depending of their role in formation of flash floods (Table 1). Setting the weights we used the information available in the literature on the impact of individual factors on the intensity of flash floods [2,4,6,11]. For each parameter, separate maps were created showing the spatial variation of its values in the catchments according to the adopted assessment criteria (divided into five classes of partial susceptibility). The synthetic susceptibility of catchments was calculated based on the following formula:

$$\text{FF} = \sum\_{i=1}^{n} \left( \mathbf{w}\_{i} \mathbf{x}\_{i} \right)^{2}$$

FF: susceptibility to flash flood formation;

wi: weight of parameter;

xi: parameter;

n: number of parameters.

Based on the partial assessments, the total susceptibility index expressed with a numerical value with a theoretical variation of 0–48 was obtained. Four classes of susceptibility to the occurrence of flash floods were distinguished:


To assess the impact of particular features (parameters) of the catchment on the final assessment results Pearson's correlation coefficients between the synthetic, point assessment result and the catchment parameters was calculated.



The occurrence of the most vulnerable catchments within administrative units was analyzed. Existing planning documents were analyzed for municipalities located within the catchments with high susceptibility to flash floods (more than 50% of the area occupied by the catchments belonging to class III and IV). It was assessed whether this threat is recognized in them and reflected in spatial planning. Twelve studies (spatial development conditions and directions study for a municipality) and over 60 local plans (spatial development plans) or their changes were analyzed. We also analyzed flood hazard and flood risk maps prepared in accordance with the Flood Directive available at the ISOK website [63]. It was assessed whether they include catchments and municipalities located within them, for which high susceptibility to flash floods was found.

#### **3. Results**

Most of the 369 catchments in this study were rather small (Table 2). The area of more than 60% was less than 20 km2. The biggest proportion of the catchments (30%) covered an area of 10 to 20 km2. Most of the large catchments were located in the western and central part of the Lublin Upland, while the smallest catchments were located in the east and north of the region (Figure 4).

**Table 2.** The parameters of the studied catchments (369 in total).


Most of the catchments (about 50%) had moderate gradients, from 2 to 3 degrees. Catchments with the highest slope gradients were primarily located in the eastern part of the Upland (Figure 4). Three concentrations of catchments with the lowest mean gradients were situated in the southernmost part of the region and in its central-northern part. Most of the catchments (44%) had a forest cover within the 10–20% and 20–40%, range. The most extensive forest cover occurred in areas in the western and eastern part of the Upland. The central part had the smallest forest cover (Figure 4). Most of the catchments (over 50% of all catchments under study) had a river network density of 0.2–0.5 km·km−2. The lowest value of this index occurred in catchments in the south-western and central part of the Upland. The highest density occurred in the north-western, south-eastern and central-northern part of the region. The circularity index of most of the catchments (60%) ranged from 0.4 to 0.6. There were no patterns in the spatial distribution of catchments with various values of this index; they were equally distributed across the entire region. The mean length of first-order watercourses in most of the catchments (30%) ranged from 2.5 to 5 km (Figure 4). Additionally, in this case, there are no distinct patterns in their spatial distribution; catchments with different values of this index form a mosaic-like pattern across the entire area of the Lublin Upland (Figure 4). Built-up areas accounted for 2–5% in 34% of the catchments and 5–20% in 29% of the catchments. Catchments where the road network ranges from 0.5 to 1.5 km·km−<sup>2</sup> were predominant. The highest road density occurred in the central part of the Upland while the lowest density in the eastern part (Figure 4).

The mean score for all catchments in the Lublin Upland was 36, which was the upper limit of susceptibility class II (Table 3). About 30% of the area belonged to class III and IV. The most susceptible catchments were scattered across the entire area of the Upland. Their biggest concentrations were located near Lublin and in the east of the Upland. The least susceptible catchments predominated in the west and south-west part. Low susceptibility also occurred in the northern part (Figure 5).

**Figure 4.** Assessment of susceptibility of catchments to the occurrence of flash floods. (**A**)—catchment area (km2), 1: <5, 2: 5–9, 3: 10–19, 4: 20–29, 5: 30–59, 6: >60; (**B**)—circularity index, 1: 0.3, 2: 0.3–0.39, 3: 0.4–0.49, 4: 0.5– 0.59, 5: 0.6–0.7, 6: >0.7; (**C**)—mean gradient in catchment (◦), 1: <1.75, 2: 1.75 –1.9, 3: 2–2.4, 4: 2.5–2.9, 5: 3–3.5, 6: >3.5; (**D**)—density of river network (km·km<sup>−</sup>2), 1: <0.15, 2: 0.15–0.19, 3: 0.2–0.29, 4: 0.3–0.49, 5: 0.5–0.59, 6: >0.6; (**E**)—mean length of first-order watercourses (km), 1: >10, 2: 7.5–9.9, 3: 5.0–7.4, 4: 2.5–4.9, 5: 1–2.4, 6< 1; (**F**)—forest cover (%), 1: 0, 2: 0.1–5, 3: 5–9, 4: 10–19, 5: 20–39, 6: >40; (**G**)—built-up area (%),1: 0, 2: 0.1–1.9, 3: 2–4.9, 4: 5–19.9, 5: 20–40, 6: > 40 and (**H**)—road density (km·km<sup>−</sup>2), 1: <0.5 2: 0.5–1.4, 3: 1.5–2.9, 4: 3–4.9, 5: 5–10, 6>10; 7—main towns, 8—main rivers.


**Table 3.** Quantitative differences of catchments with different degrees of susceptibility.

**Figure 5.** Synthetic assessment of susceptibility of catchments in the Lublin Upland to the occurrence of flash floods. 1—Susceptibility class I, 2—Susceptibility class II, 3—Susceptibility class III, 4—Susceptibility class IV, 5—main towns, 6—main rivers, 7—major flash floods (1960–2020).

Catchments belonging to Class I show a low level of susceptibility to the formation of flash floods. Most of the catchments in this class covered a large area (mean area of 28 km2) and had a large forest cover (24.7%). The lower mean gradient of the catchment area, 2.1, was a characteristic feature of these catchments. They also had a poorly developed river network, with a density of 0.2 km·km−2, while the length of first-order watercourses was 4.5 km. The mean road density was 1.47 km·km<sup>−</sup>2, while built-up areas accounted for 2.6% (mean) of the area of these catchments.

Catchments assigned to class II show a low susceptibility to rapid rises in water levels and runoffs. It is the most numerous class, comprising nearly half of the catchments. Catchments in this class typically covered a rather large area (mean area of 22.1 km2) and had a rather small forest cover (17.4%). The density of their river network as rather low, 0.26 km·km−2, while the mean length of first-order watercourses was 4 km. The road network density was 1.99 km·km−<sup>2</sup> while built-up areas accounted for 3.9% of these catchments.

Catchments belonging to class III were susceptible to the formation of flash floods. Their area was considerably smaller than those in the previous classes: 15.2 km<sup>2</sup> on average. The slope gradients (2.6◦ on average) were slightly higher than in class I and class II catchments. The proportion of forests in the land cover of these catchments was small (9.2%). The mean length of first-order watercourses, 2.4 km, was clearly shorter, while the proportion of built-up areas was greater, 7.1%. The density of the road network was similar to the value for class II catchments.

Class IV comprised catchments highly susceptible to flash floods and runoffs. Their area was small, 7.5 km2 on average. The mean slope gradient, ranging from 1.5 to 0.71, was the highest among all the classes. The proportion of forested areas was very small, 1.8% on average, but that of built-up areas was high, 23%. The density of the river network in these catchments was the highest, 0.6 km·km−2, while the mean length of first-order watercourses was the shortest, 1.9 km.

Table 4 contains correlation coefficients between the synthetic susceptibility (expressed in points) and the characteristics (parameters) of the studied catchments. Table 5 provides information on the basic features and existing planning documents for municipalities with a high degree of susceptibility to flash floods. Table 6 presents the results of the analyses of existing flood hazard and flood risk maps within the surveyed municipalities. It also presents information on the scope of flood hazard and flood risk identified in the planning documents.

**Table 4.** Correlation coefficients between catchment susceptibility and catchment parameters.


**Table 5.** Selected characteristics of municipalities with high flash flood risk (>50% of the area in class III and IV).


Source: own study based on the Local Data Bank of the Central Statistical Office of Poland (2019), \* according to the 2010 Agricultural Census, \*\* data from 2014, "-" no data.

*Resources* **2021**, *10*, 14


**Table 6.**

Provisions of planning documents

 vs. flood hazard in

municipalities

 (>50% of the area in class III and IV).


*Resources* **2021**, *10*, 14

**Table 6.** *Cont.*

#### **4. Discussion**

The studies conducted so far indicate that the Lublin Upland is an area where flash floods occur [9,14,16]. However, the frequency of these phenomena is not as high as in mountain areas. On the other hand, the degree of spatial development in the Upland was greater. The analysis of maps showing the susceptibility of catchments to flash floods and the locations where heavy rains occur indicates the existence of a real threat [14]. In the second half of the 20th century, heavy rains with a volume of more than 30–40 mm within 1–2 h were estimated to have a frequency of 1 event per 20–30 years in the Lublin Upland [14]. However, flash floods can occur in the same locations with a greater frequency, as it is the case in the catchment of the Sanna river or in the area of Lublin (Figure 6). The question of the spatial distribution of these phenomena requires further investigation because systematic research in this respect has not been conducted so far. Although the applied method of identifying catchments susceptible to flash floods is of a preliminary and de facto qualitative character, it can be useful in the spatial planning process. It allows one to identify the areas where the susceptibility is the highest. Major flash floods of the last 50 years occurred in the catchments of the IV class (Figure 5). The parameters analyzed had a varying impact on the susceptibility of catchments to flash floods. The high proportion of built-up areas, small share of forests and small catchment area had the greatest synthetic susceptibility of catchments to flash floods (Table 4).

In accordance with Polish law, a preliminary flood risk assessment was carried out for the Lublin Upland. Flood risk maps and flood hazard maps were drawn up for the areas at risk. They are available on the ISOK map portal [63]. The sheets of this map encompassed all the major rivers of the region and some of the smaller rivers. The analysis of flood hazard maps and catchments at risk of flash floods showed that these areas were not always reflected in the flood risk maps and flood hazard maps (Table 6). Particularly small catchments, located in the upper reaches of small watercourses, were not taken into account on flood hazard maps even if floods occurred there historically (Figure 5).

Flash floods are a separate problem, particularly in small catchments because their scale and intensity are difficult to predict. The prepared susceptibility assessment revealed catchments at risk of flash floods based on the adopted parameters. A high flash flood hazard in the Lublin Upland results from the specific land relief, high degree of deforestation and considerable share of arable land. Due to these characteristics, along with the prevailing land use pattern (fields perpendicular to the valley axis), water after heavy rainfall is quickly drained from the plateau top and slopes (also via gully systems with hard roads) to flat-bottomed valleys. Buildings, historically located usually along the edge of the valley bottom, are threatened with flooding. The situation within territorial units with a high share of built-up and urbanized areas is particularly difficult. In June 2019, a flood occurred successively in Pasieka, Wierzchowiska Drugie and Wierzchowiska Pierwsze—localities lying in the valley of the small Sanna river in Modliborzyce municipality. Houses and roads were flooded, part of the technical infrastructure was damaged. The valley was outside the scope of the prepared sheets of the flood hazard maps. However, the river had already flooded there before (Figure 6). A similar situation took place in Siedliska Drugie in Fajsławice municipality where, in 2016, a flash flood occurred in the part of the valley not included in the flood hazard maps.

Not all rural municipalities and towns of the Lublin Upland make full use of planning instruments to appropriately manage space, also in the context of flood hazards (Table 5). In the case of 13 units of territorial division with a high level of flash flood hazard (thirdand fourth-degree hazard in over 50% of the area), a high percentage of the area is covered by local plans in only six of them. What is more, some of these plans were drawn up a long time ago and do not guarantee a comprehensive approach to flood hazard. In several municipalities, only a few percent of their area are included in the local plans. It is also quite alarming that local plans exist for only half of the territory of the region's capital city Lublin. Detailed analysis of local plans shows to what extent the risk has been identified and how it has been taken into account in planning documents (Table 6).

**Figure 6.** Effects of a flash flood in the valley of the Sanna River in Modliborzyce municipality (June 2019) (source: https://modliborzyce.pl/2312-miesi ˛ac-po-powodzi-cz-1.html, accessed on 20 December 2020).

The inclusion of 100-year water ranges (Q1%) in planning documents does not fully address the flash flood hazard because with rapid rises in water levels, the flows can even exceed the range of a 500-year water (Q0.2%). The criteria for the preliminary flood risk assessment are not fully effective with regard to small catchments with big elevation differences and agricultural land use. Only a few studied planning documents take into account the phenomenon of flash floods. Its spatial range is indicated only in the case of overlapping with the risk of "classic floods". In the recently developed planning documents, the flood risk is determined on the basis of the FHM and FRM, which do not fully take into account the flash flood hazard. Planners do not know the criteria for separating flood extents, therefore FHM and FRM require a more complete flash flood risk. Even if they have information about the phenomenon (identify the areas of occurrence in the study), the basis for the findings in planning documents, in accordance with the law, are FHM and FRM. No flood hazard maps and flood risk maps have been prepared for many of such areas [7,33]. Such a situation also occurs in the Lublin Upland. Even if such maps exist, spatial development plans do not fully cover areas at risk of flash floods (Table 6). The decisions on development conditions and land management do not always address the hazard adequately.

In Lublin Upland the flood hazard ranges have been specified in the case of areas located in the catchments of larger rivers. However, areas located in the catchments of smaller watercourses are usually regarded as safer while in fact they are particularly exposed to the flood hazard in the case of heavy rains [7,33]. Flood hazard maps and flood risk maps are very important not only for planners, including urban planners, but also for the crisis management cycle: from the prevention phase, through the preparation and response phase, to the reconstruction phase. There is also an issue of connecting the identification of hazards based on natural criteria with the possibility for action at the level of administrative divisions. Spatial planning is the domain of the authorities of territorial units established by way of administrative decisions. The authorities responsible for water management operate within units having natural boundaries. This system needs to be integrated, and this remains a challenge not only in Poland. Flood risk reduction can be achieved through a proper spatial planning process, which is based on reliable information on flood hazards. This enables the designation of areas to be excluded from building development or the identification of technical restrictions and requirements for the location of buildings to be introduced.

A full coordination between spatial development policy and entities responsible for flood risk management is a challenge not only in Poland. The connection between the spatial planning system and flood risk management system needs to be strengthened. As a preliminary step, spatial planning should be aimed at reducing the risk and consequences of natural disasters [40,70]. Gralepois (2020) [38] points out that spatial planning has not been fully used in the prevention of floods and its importance was appreciated to a greater extent only with the implementation of the Flood Directive. However, as the examples of England and France show, the choice of planning instruments is not always satisfactory, particularly in the context of conflicts between the local tier in spatial planning and national legislation and risk management. In the Netherlands, on the other hand, flood prevention is better integrated into spatial planning, which is a result of greater awareness and better integration of flood management. However, Neuvel and Van Den Brink (2009) [71] indicated that in many cases, even if flood risk information exists, it is not always adequately used.

An important factor in mitigating the risk of flooding is to reduce the vulnerability to flooding, which means the degree to which people, their property and facilities are prepared for flooding, and the ability to repair damage and rebuild after flooding has occurred. Measures related to the reduction of vulnerability include preparing residents for the hazards, i.e., measures related to the protection of buildings at risk of flooding, implementation of flood warning systems and flood education, in the broad sense of the term, among the decision-makers and residents [72]. The episodic nature of flash floods means that residents are not aware of the risks and are not properly prepared for the occurrence of flash floods: they do not know how to properly secure their property or how evacuation is conducted [73]. Fortunately, flood warning systems are used to a greater degree, using devices to signal the danger of flooding when the water level in a watercourse or the amount of precipitation exceed a set limit [7,74,75]. Mobile telephony can also be used to quickly and directly inform people in vulnerable areas.

#### **5. Conclusions**

The amount of available data on the occurrence of flash floods in the Lublin Upland is not extensive. The catchments with high susceptibility covered about 30% of the studied area. Most severe flash floods in the second half of 20th century occurred in the catchments of the IV class. It seems, therefore, that the method can be used by local government units.

In Poland currently, areas at risk of flash floods are not fully taken into account in the spatial planning process. Few planning documents take into account the phenomenon of flash floods, and its spatial range is indicated only in the case of overlapping with the risk of "classic floods". It is advisable to include in the legal system the requirement for preliminary and, in justified cases, detailed analyses of this hazard. Planners need spatial information and, therefore, there is a need to expand the areas for which flood hazard maps and flood risk maps are drawn up.

A serious problem in units of territorial division is the lack of local plans in which it would be possible to include appropriate guidelines for development and building in areas at particular risk of flooding because the procedure for preparing them ensures a better level of protection than it is the case with decisions on the site-location of public-purpose investment projects and decisions on development conditions. Additionally, the flood risk management system is undergoing constant legal and structural change, which does not allow its efficiency to be properly assessed.

A very important issue is the question of educating society about this type of phenomena. In addition to the existing recommendations in the legal system, it is necessary to make the inhabitants of areas at risk of flash floods aware of the possibility of such phenomena, even if they are not located in the valleys of large rivers.

**Author Contributions:** Conceptualization, W.Z., B.B.-Z. and D.G.; methodology, W.Z., D.G. and B.B.-Z.; investigation, D.G. and B.B.-Z.; writing—original draft preparation, W.Z. and B.B.-Z.; writing review and editing, W.Z. and B.B.-Z.; visualization, W.Z. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** All sources of the publicly available datasets are provide in the text as references.

**Acknowledgments:** The authors wish to thank the Editors and anonymous reviewers for their valuable comments and suggestions to improve the quality of this paper.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**

