Wiki Wiki

« Back to FrontPage

Grandi Laghi Lombardi - ENVIRONMENT

MANAGEMENT ACTIONS FOR PRESERVATION OF THE PREFERABLE ENVIRONMENTAL CONDITIONS FOR BROWN AND MARBLE TROUT IN  THE RIVERS ADDA AND TICINO  

Content

1. Abstract

2. Introduction

3. Background of the case study

    3.1. Basic Legal Framework for Water Quantity and Quality Protection in Italy

    3.2. Basic information of the Italian Agency for Environmental Protection and for Technical Services

    3.3. Motivation of study

    3.4. Area of interest

     3.4.1 Location

     3.4.2 Species of interest

4. Study Analysis

    4.1. Thresholds Selection

    4.2. Objectives of the Study

    4.3. Performance Indicators

    4.4. Conflict

5. Results

   5.1. Analysis of scenarios

   5.2. Visualization and selection of preferred alternatives

   5.3. Improvements from current situation

   5.4. Analysis of condition 1

6. Conclusion

7. Reference

8. Authors

9. Appendices

    Appendix I Condition 1, Performance Indicators

    Appendix II Condition 2, Performance Indicators

 

 

 

1. Abstract

In this wiki page is presented a group research project about Grandi Laghi Lombardy done for NRM-IWRM , Spring Semester 2015. The stakeholder is Italian Agency for Environmental Protection and Technical Services, and among its several duties, and empowered by law, developed a case study to analize the conservation of marble and brown trout in the rivers Ticino and Adda in the Region of Lombardy. A minimum water depth (0.7m) and an optimal velocity (0 – 0.6 m/s) were identified for the welfare of trout species, flows related for this condition, and for maximum height to avoid flooding were computed using OPflow (Escobar, 2006). In order to comply with these conditions, and minimize the deviations of optimal flows, three new scenarios for River Adda and River Ticino were developed (Decreasing Flow, Increasing, and Seasonal Flow), simulated using WEAP (Water Evaluation and Planning System) (Stockholm Environment Institute, 2015), including other stakeholders (Irrigation, Hydropower and Flooding Prevention) to simulate conflict situations, and evaluated computing performance indicators defined in this paper such as Reliability and Vulnerability using Matlab algorithms (The MathWorks, 2015). A preferred scenario is selected using visualization tools (Discovery DV, 2015). The alternative selected for both systems (Adda and Ticino) is a seasonal flow, increasing reliability in river Adda, improving vulnerability but decreasing Irrigation reliability; as in for Ticino River, performance indicators were found to be already optimal in current situation, but the seasonal alternative increases reliabilities to other stakeholders such as Flooding prevention and Hydropower generation, decreasing in a little amount Irrigation reliability.

2. Introduction

Environmental protection works on preserving the natural environment, for the benefit of society and ecosystems. Humans and their activities have degraded the biophysical environment, sometimes permanently. Governments have started constraining some of these activities for the welfare of environment preservation (Solomon 2010). The Italian Agency for Environmental Protection and Technical Services (APAT), which is in charge of the scientific and technical activities at the national level to protect the environment, is continuously developing studies in the Grand Laghi Lombardy Region, focusing on the environmental problems related to lake and river basins. The quality and quantity of water are the main problems to be faced in this region as in many others.

In this research, the main focus of the Agency is to determine suitable conditions for trout species in Ticino and Adda River, which are identified as minimum depth and preferred velocity; analyze time series of collected data for lake levels and their inflows; develop and compute performance indicators for multiple proposed scenarios, and recommend a preferred alternative for trout welfare and other stakeholders performance.

The retrieved data was from two cross-sections (AIPo, 2011). One cross-section for Ticino River, with location at the area of  Parco Regionale del Ticino and the other for Adda River which is located at the area of  Parco Regionale Adda Sud. The optimal velocity and minimum depth were determined by using the software OPFlow (Escobar, 2006). After analyzing the current situation in WEAP (Water Evaluation and Planning System) (Stockholm Environment Institute, 2015) the results of performance indicators show that there is need of improving the system. Three scenarios are proposed, decrease minimum environmental flow, increase, and develop a seasonal minimum flow. Time series of proposed scenarios and current one are computed in WEAP for all the stakeholders involved, Irrigation Sites, Hydropower Generation, Flooding Prevention and Trout Conservation.  Performance indicators for all stakeholders are computed using algorithms in Matlab (The MathWorks, 2015) created by each stakeholder. The software DiscoveryDV by DecisionVis (2014) has been used to identify the Pareto front, discuss alternatives and select the preferred one.

Figure 1. Location of Study Area (Google Maps, 2015)

3. Background of the case study

3.1. Basic Legal Framework for Water Quantity and Quality Protection in Italy

In Italy the regions’ duty is to monitor water activities, and central government should supervise, coordinate and regulate tasks. Basic legal framework to control water quantity and quality was compiled by Premazzi in 2003:

 

1. Legislative decree number 152/99, which transposes the European Union (EU) Directives 91/271/EEC and 91/676/EEC, and defines the main requirements for water quality monitoring in inland waters, coastal waters, estuaries and lagoons (Decreto Legislativo 1999).

2. Legislative decree number 258/00 (Decreto Legislativo 2000), which concerns the protection of water from pollution and integrates thoroughly some topics of the legislative decree 152/99 (Decreto Legislativo 1999). For the first time in Italy, the two decrees set environmental and functional objectives for water bodies.

3. Law 183/89 (Repubblica Italiana 1989) which establishes river basins as the unit where environmental protection activities have to be designed and performed, and creates river basin authorities.

4. Law 36/94 (Repubblica Italiana 1994a) which concerns the reorganization of the public services that are charged with water abstraction, water supply and distribution, and waste water treatment.

5. Law 61/94(Repubblica Italiana 1994b) which relates to the reorganization of environmental controls and the National Agency for Environmental Protection and Regional Agencies.

 

3.2. Basic information of the Italian Agency for Environmental Protection and for Technical Services

The Agency for Environmental Protection and Technical Services (AEPT) develops scientific and technical activities to protect the environment, in a national framework; it was created by merging the National Environmental Protection Agency with the Department for National Technical Services of the Presidency of the Council of Ministers. AEPT is formed by a network of regional agencies for focused on environmental protection as well, with the purpose of exchanging information and guaranteeing environmental conservation. It combines local expertise with national contribution and jurisdiction. The responsibility for environmental protection and monitoring is therefore on the hands of regional institutes, complying with national legislations. The monitoring of programs is carried out at the local level, on a case-by-case basis. (INSPIRE, 2015)

3.3. Motivation of study

The main purpose for developing this study is to analyze the current situation in Grandi Leghi region, Italy in order to make a new water management strategy that will prevent the environment from depletion. One of the important environmental issues in Italy is Water pollution. But also the nation's waters in rivers and lakes have been over used by industrial and agricultural customers. These particular spices (brown and marble trout) are taken in consideration as indicator of welfare of the ecosystem in these rivers. The both trout species are chosen for this study because of their sensibility of the water quantity and quality changes. (Encyclopedia of the Nations, 2007)

3.4. Area of interest

3.4.1. Location

This case study is situated in Lombardy region, northern Italy. Major rivers are Ticino, the outlet of Lake Maggiore and the Adda, outlet of Lake Como. Those waters are habitat for various species.

River Adda raises in the Alps, close to the border of Trentino - Alto Adice and Lombardy region, near city of Bormio. Then it flows towards Lake Como, enters into it at province of Colico. Its outlet from the lake is in the Lecco province. Adda is a tributary of the Po river and their confluence point is close to Cremona (Lombardy). Length of the Adda river is 313 km.

.

Figure 2. Observed cross section at River Adda (Source)

River Ticino raises in Switzerland, close to place called Bedretto. It represents boundary between Lombardy and Piemonte regions. It flows into the lake Maggiore at province of Verbania (Switzerland) and then outflows from lake at Sesto Calende (Italy). Its length is 248 km. As well as Adda river Ticino is tributary of the Po. Confluence point is close to city of Pavia.

Figure 3. Ticino River (Source)

3.4.2. Species of interest

Brown Trout ( Salmo trutta )

The brown trout is European species of salmonid fish (Figure 4). The average size is usually 0.1 to 1.8 kg. Small brown trout feed heavily on zooplankton, insect larvae and amphipods (Raleigh 1986). Brown trout mature as early as the end of their first year, but most mature in their third to fifth year. They are typically stream spawners. Optimal brown trout riverine habitat is characterized by clear, cool to cold water.

Figure 4. Brown trout (Source)

Marble Trout (Salmo marmoratus )

The marble trout is a freshwater fish species in the salmonid family (Figure 5). It is characterized by distinctive marbled color pattern and high growth capacity. The marble trout is found in only three basins and two rivers of the Adriatic basin. One of those basins is Po with its northern tributaries.

Figure 5. Marble trout (Source)

4.Study Analysis

4.1. Thresholds Selection

The velocity and depth of water are the factors to be measured for suitability conditions of Marble and Brown Trout, and for both species is assumed the same suitability conditions (Balkan Trout Restoration Group, 2005)  

Cross-sections of interest were identified according to existing projects interested in conservation of Marble Trout in both rivers, for Ticino the cross-section selected is 49 (AIPo, 2011) close to Parco Regionale del Ticino (Riserva Somin, 2010) and for Adda is 35 (AIPo, 2011), close to the area of Cremona (Provincia di Cremona, 2015), both from the last existing survey.

Information about habitat suitability index for these species was not found for Ticino and Adda river (rivers of this study); it is proposed to transfer the habitat suitability curves from river Sesia and Adige (Autorita di Bacino del Fiume Adige, 2002) to the rivers of this study. The following image shows the information required about preference depth in river Sesia that was proposed to be transferred to Adige and in this study will be transferred to Ticino and Adda.

Figure 6. Preference curve of deepness for young trout (Autorita di Bacino del Fiume Adige, 2002)

Figure 7. Preference curve of deepness for adult trout (Autorita di Bacino del Fiume Adige, 2002)

The depth value of 70 cm is selected as a minimum threshold value for this study, since is the optimal value for adult fish requirements (Figure 7), for young trout will be met close to the banks where depth is lower than the maximum depth of cross-section.

The optimal velocity of the water for river Sesia and Adige was found to be different from each other, and not transferable (Autorita di Bacino del Fiume Adige, 2002).

Figure 8. Frequence of velocity preference for trout (Autorita di Bacino del Fiume Adige, 2002)

This figure 8 shows the maximum velocity where adult fish were captured in river Adige (Autorita di Bacino del Fiume Adige, 2002), and will be transferred to Ticino and Adda, assuming similar morphological aspects, such as slope and river bed material, and geographical location, therefore, the threshold for maximum velocity for this study will be 0.60m/s (mean velocity); requirements for young trout will be met on other locations of cross-section, where velocity is lower than the mean (close to the banks).

Using the software OPflow (Escobar, 2006), the cross-sections of interest were modeled inputting data of slope of river (0.1 for Ticino River, and 0.08 for Adda), roughness coefficient (Ks=25),  and the shape and elevation of the cross-sections, obtaining a table containing height and velocity for each water flow value.

Desired flows were identified for the preferred height and velocity mentioned as a threshold (max. vel. 0.60m/s and minimum height 0.70m), and are the following values:

Ticino River: 7 – 30  m3/s

Adda River: 9.2 – 42 m3/s

Field observations and revealed that even when velocity is high, areas of the river with still water or with small velocities were found by fish, close to banks, in deeper areas, etc.

Figure 9. Fish location in a stream (Neophyte Fly Fishing Basics 2011)

Figure 9 shows different conditions in a river stream where fish can be found due to small velocities.

Due to these observations two conditions will be analyzed, the one for minimum and maximum preferred flow derived from depth and velocities, and the second condition where only the minimum flow is used to assure depth requirement and a maximum flow identified in the flow-velocity-height tables (knowing the shape of cross-section and banks location) for avoiding inundations in the area.

The first condition is as mentioned before

Ticino River: 7 – 30  m3/s

Adda River: 9.2 – 42 m3/s

And the second condition is

Ticino River: 7 – 1000  m3/s

Adda River: 9.2  m3/s (only minimum since no flood occurs in the cross-section for available flows computed by the program OPflow)

This two conditions are set as thresholds in an algorithm using Matlab to identify the performance indicators for a time series analysis obtained doing simulations in WEAP for different proposed scenarios, although only condition 2 is analyzed with other stakeholders.

Condition 2 is the critical condition to be met, since as shown in Figure 9, fish will find locations with lower velocities than the mean velocity of the river stream; the minimum depth is identified as the crucial suitability condition.

4.2. Objectives of the Study

In order to preserve trouts environment in rivers, following objectives are defined:

·         Minimization of deviations from optimal water flow in the rivers Adda and Ticino: Optimal water flow ranges for brown and marble trout were found to be (using condition 2) : in case of Adda only a minimum flow of 9.2 m3/s, no upper boundary, and in case of Ticino 7 – 1000  m3/s . The release from the reservoir affects the water flow in the downstream river, the aim of this objective is to find an adequate policy that minimizes these deviations.

4.3. Performance Indicators

Data collected for time series of lakes levels and inflows is analized through the following performance indicators, using the program Water Evaluation and Planning System (WEAP) and MatLab. Multiple scenarios will be simulated to find suitable water release policies from the lakes to guarantee welfare conditions for trouts conservation.

§  Reliability of Dv : “The reliability of time series can be defined as the number of data in a satisfactory state devided by the total number of data in the time series”. (Loucks 2005)

Reliability = [ # of Dv=0 ] / [Total number of times]

Equation 1. Computation of Reliability

Satisfactory state for preferable Flow for Adda River represents all the date of time series that comply with the minimum  9.2 m3/s, and for Ticino in the interval from 7 m3/s to 1000 m3/s .

§  Vulnerability of Dv: “Is a measure of the extent of the differences between the threshold value and the unsatisfactory time series value”. (Loucks 2005)

Vulnerability = [ SUM of Dv] / [ Times when Dv occurs ]

Equation 2.  Computation of Vulnerability

The performance indicators are computed for time series of the current situation, from 1974 to 2010, and different scenarios are proposed simulating different environmental flow requirement, likewise, situation for other stakeholders affected by possible management policies is simulated.

The stakeholders involved are: Hydropower generation, Irrigation demand and Flooding prevention.

Objectives of other stakeholders are identified as the following:

§  Hydropower: Maximize the hydropower production, by providing more water.

§  Irrigation: Maximize revenues, by providing enough water demand.

§  Flooding prevention: Minimize flood risk, by reducing water level in lake.

Figure 10. The 2 river systems, where Demand Sites is Irrigation sites, Flow requirement is the one for Trouts, Run of River Hydro is Hydropower generation, and Flood prevention is on the lakes, presented as reservoirs

4.4. Conflict

Flow requirement has a priority of 1, this means that all the other stakeholders will be affected if flow requirement changes, and is understandable from the picture that if requirement increases, it conflicts with Irrigation, since they cannot withdrawal water from the river, hydropower generation conflicts with irrigation as well for same reason.

These conflicts are the visible ones, but some of them are expected to occur, since is not possible to predict all of them regarding the complexity of the system, therefore, running scenarios is needed to find a possible solution for the management problem.

Each of the stakeholders (including Trout Preservation) developed performance indicators for this objectives and a Matlab algorithm to compute them from data of time series given by WEAP.

5. Results

5.1. Analysis of scenarios

For the analysis of scenarios and comparisons with other stakeholders, the maximum flow velocity is not taken into account (condition 1), and only a maximum flood to avoid floods will be analyzed (condition 2).

Three scenarios are proposed in addition to the current (do nothing) alternative:

§  Current situation: Minimum environmental flow equal to 13 m3/s in Ticino River, and 5m3/s in Adda.

§  Decreasing Environmental Flow:  This scenario is proposed to understand what would happen if flow decreases along the reaches. Minimum environmental flow equal to 7.5  m3/s in Ticino River, and 4 m3/s in Adda.

§  Increasing Environmental Flow:  It is proposed to understand what would happen if flow increases and how it impacts on other stakeholders. Minimum environmental flow equal to 15  m3/s in Ticino River, and 9.5 m3/s in Adda.

§  Seasonal Flow: Conditions for spawning seasons of Trout are identified, decreasing flow from October to February (spawning period) when lower velocities are needed and increasing from March to September (Lustrik 2015), and values for minimum environmental flow are set for Ticino in 7 m3/s during spawning period, and 13 m3/s for other months. The situation in Adda is set as follows: 5 m3/s during spawning period, and 9.5 for other months.

Results of performance indicators (Reliability) are computed using the Matlab codes (Irrigation is computed as an average of the existing demand sites of this stakeholder), and a software for visualization, Discovery DV is used to understand the impact of the alternatives in all stakeholders and identify the Pareto Optimal Solutions.

5.2. Visualization and selection of preferred alternatives

Figure 11. Visualization of Ticino River Alternatives performance

This figure 11 shows the analysis of scenarios in Ticino River, the optimal Pareto solutions are Decrease and Seasonal. To emphasize them on the image, cubes have been used.

Decrease scenario has been shown as preferable alternative for stakeholders representing Irrigation Ticino, Hydropower Ticino and Environmental Agency, but it is not preferable for Flood Protectors. On the other side seasonal alternative is preferable for Hydropower, moderate for Environmental Agency, Irrigation Ticino and Flood Protectors. Since Environmental Agency is more interested in preservation natural habitat with respect to irrigation, the preferred management policy is to operate the Ticino river system using seasonal variations for minimum flow requirement, giving a reliability of 99.32% and vulnerability of 1,250 m3/s (Table 1, Appendix 2) which is above the maximum flow (Table 2, Appendix 2), and absence of vulnerability for minimum requirement, this means that the minimum flow is always met, but flooding occurs few occasions when the system is not reliable.

Minimum Environmental flow is set equal to 7 m3/s from October to February (spawning period) and increasing from March to September to 13 m3/s.

Figure 12. Visualization of Adda River Alternatives performance

This figure shows the analysis of scenarios in Adda River, the optimal Pareto solutions are all of the proposed scenarios, except the current situation. In the figure, Pareto front is identified as in the previous one. Among the Pareto solutions seasonal alternative has been shown as the preferable one. Reason for this is that decrease alternative is good for Irrigation but poor for Environmental Agency. That opposite situation has been derived from increase alternative. Reliability for Environmental Agency has reached its maximum, but reliability for the irrigation has dropped to its lowest value. 

Seasonal alternative (preferred) is giving a reliability of 70.27% (Table 1, Appendix 2) and vulnerability of 5.1 m3/s which is below the minimum flow (Table 2, Appendix 2), and absence of vulnerability for maximum flow desired because flood doesn’t occur for collected and computed data, and when system is not reliable, the vulnerability is still higher than the current situation minimum flow, and higher than the minimum selected for spawning season, in conclusion, this alternative is acceptable.

Seasonal minimum flow requirement is set equal to 5 m3/s from October - February, and 9.5 m3/s for other months.

5.3. Improvements from current situation

Reliability and vulnerability for Ticino system remains the same, 99.32% and 1250m3 respectively, the change of policy relies on the fact that Seasonal Scenario is on Pareto front and Current Scenario is not, increasing with this other stakeholders performances, in this case, Hydropower Generation and Flooding Prevention, lowering in a small amount reliability of Irrigation.

For what it concerns Adda River, Reliability has increased in a considerable amount, from 30.4% to 70.27% and the vulnerability has improved from 4.4 to 5.1 m3/s, although Reliability for Irrigation has decreased as shown in Figure 12.

5.4. Analysis of condition 1

In addition to previous computations and results, an analysis has been performed for the condition 1 (when included maximum flow velocity). Values for maximum water flow that have been used are 47.5 m3/s for Adda and 30 m3/s for Ticcino. Same as previous four different scenarios are taken into account to compute performance indicators in this condition. Although better results for Reliability in this condition are found in the Increasing Flow scenario (table 1, Appendix 1), the values for Seasonal alternative are acceptable, since as previous mentioned in Figure 9, fish will find other locations where velocity is lower than the mean velocity of the stream. Reliabilities of the preferred alternatives selected (Seasonal) are 53.82% and 46.39% for Adda and Ticino respectively (for condition 1). Reliabilities for other alternatives are given in table 1-Appendix1.

6. Conclusion

Seasonal scenario was selected as preferred one for both systems (Ticino and Adda) and mediating conflicts among stakeholders, with reliability of 99.32% for Ticino and 70.27% for Adda intended for preferred flows in condition 2, when stream flows are computed for minimum depth and maximum level related to flooding (from 7 m3/s to 1000 m3/s for Ticino and only minimum 9.2 m3/s for Adda, since no flooding occurs for available flows computed by the program OPflow). Vulnerability for 2 systems are 1250 m3/s for Ticino, which means that floods occur when system is not reliable, but minimum flow is always met, and 5.1 m3/s for Adda, meaning that when system is not reliable, the average flow is still bigger than the selected for spawning seasons, and flooding doesn’t occur, therefore alternative is acceptable.

For Ticino River, improvements have been made for other stakeholders, since conditions don’t change for Trout conservation, the improvements are related to Hydropower Generation and Flood Prevention.

For Adda river, improvements have been done for Trout Preservation, but Irrigation has decreased reliability.

Recalling the objective of the study, minimize deviations from preferable flows, as a result the deviations have decrease from current situation in River Adda; as in for Ticino River, conditions were already good for trout in current scenario and have maintain the same.

7. Reference

AIPo Agenzia Interregionale perl il fiume Po, 2011,  Geoportale, Parma Italy

Balkan Trout Restoration Group, 2005, Marble Trout, Online

DecisionVis LLC (2014), DiscoveryDV, State College, PA, USA.

Decreto Legislativo (1999) Disposizioni sulla tutela delle acque dall’inquinamento e recepimento della direttiva 91/271/EEC concernente il trattamento delle acque reflue urbane e della direttiva 91/676/EEC relativa alla protezione delle acque dall’inquinamento provocato dai nitrati provenienti da fonti agricole, DL No. 152, No. 124.

Decreto Legislativo (2000) Disposizioni correttive e integrative del decreto legislativo, No. 152 (11 Maggio 1999) in materia di tutela delle acque dall’inquinamento, a norma dell’articolo 1,comma 4, legge No. 128 (24 Aprile 1998), DL No. 258, No. 218.

Encyclopedia of the Nations, 2007, Italy - Environment, Online

Escobar Priscila, 2006, Opflow educational software, Politecnico di Milano, Milano, Italy

Google Maps, 2015, Google Technology Company. USA.

INSPIRE, 2015, European Commision, Infrastructure for Spatial Information in the European Community, Online

Loucks et al. Water Resources Systems Planning and Management: An Introduction to Methods, Models and Applications  2005 UNESCO.

Lustrik Rok 2015, Marble trout - Salmo trutta marmoratous, Online, Slovenia.

Neophyte Fly Fishing Basics, 2011, How to read a stream, Online, USA.

Premazzi et al 2003, Lake management in Italy: the implications of the Water Framework Directive, Lakes and Reservoirs: Research and Management 8: 41-59.

Provincia di Cremona, 2015, Progetto Trota Marmorata, Online, Cremona, Italy

Repubblica Italiana (1994a) Disposizioni in material di risorse idriche. No. 36.

Repubblica Italiana (1994b) Conversione in legge, con modificazione, del decreto-legge numero 496 (4 Dicembre 1993), recante disposizioni urgenti sulla riorganizzazione dei controlli ambientali e istituzione dell’Agenzia Nazionale per la Protezione dell’Ambiente. No. 61.

Repubblica Italiana (1989) Norme per il riassetto organizzativo e funzionale della difesa del suolo. No. 183.

Riserva Somin, 2010, Progetto Life "Trota Marmorata", Online, Abbiategrasso, Italy

Stockholm Environment Institute, Water Evaluation and Planning System - Why WEAP?  ONLINE Copyright 2015, Date of Consulting: 13-04-2015

The MathWorks, Inc. © 2015  MATLAB and Simulink are registered trademarks of The MathWorks, Inc. Natick, Massachusetts, United States.

8. Authors

Angelovska Jana, M.S. Student, Politecnico di Milano, 2015 Italy

Jovanovic Stefan, M.S. Student, Politecnico di Milano, 2015 Italy

Ramos Mejia Jose Alberto, M.S. Student, Politecnico di Milano, 2015 Italy

Professor: Rosenberg David E., PhD Civil and Environmental Engineering, Utah State University/Politecnico di Milano, 2015 Italy

Teacihng assistant: Cominola Andrea, PhD Candidate, Politecnico di Milano, 2015 Italy

 

9. Appendices

 

Appendix I Condition 1, Performance Indicators

Interval of preferred flows: 9.19 m3/s - 42 m3/s for Adda and  7 m3/s - 30 m3/s Ticino

Table 1.I.  Reliability (%) of 1st. condition  (min. depth - max. velocity)

Scenario

Adda

Ticino

Current  Scenario

13.3

47.07

Increasing  Env. Flow

80.63

47.3

Decreasing Env. Flow

13.3

46.17

Seasonal Env. Flow

53.82

46.39

 

Table 2.II. Vulnerability (m3/s) in 1st. condition

Scenario

Adda

Ticino

Vulnerability Above

threshold

Vulnerability Below

threshold

Vulnerability Above

Threshold

Vulnerability Below 

threshold

Current  Scenario

127.9

4.49

51.43

2.84

Increasing  Env. Flow

126.74

5.23

47.3

244.33

Decreasing Env. Flow

127.53

4.16

46.17

242.59

Seasonal Env. Flow

127.39

5.1

242.65

/

 

Appendix II Condition 2, Performance Indicators

Interval of preferred flows: Adda 9.19m3/s - NA; Ticino 7m3/s -1000m3/s

Table 1.II Reliability (%) 2nd condition (min. depth - flood).

Scenario

Adda

Ticino

Current  Scenario

30.4

99.32

Increasing  Env. Flow

97.52

99.32

Decreasing Env. Flow

30.4

100

Seasonal Env. Flow

70.27

99.32

 

Table 2.II.  Vulnerability for 2nd condition (m3/s)

Scenario

Adda

Ticino

Vulnerability Above 

threshold

Vulnerability Below 

threshold

Vulnerability Above 

threshold

Vulnerability Below 

threshold

Current  Scenario

/

4.4

1250

/

Increasing  Env. Flow

/

5.23

1250

/

Decreasing Env. Flow

/

4.16

/

/

Seasonal Env. Flow

/

5.1

1250

/

 

13 Attachments
1942 Views
Average (0 Votes)
The average rating is 0.0 stars out of 5.
Comments