Georgia – FutureWater

This glacio-hydrological assessment delivered river flow estimates for three intake locations of hydropower plants in Nakra, Georgia. The assessment included the calibration of a hydrological model, daily river discharge simulation for an extended period of record (1980-2015), and the derived flow duration curves and statistics to evaluate the flow operation of hydropower turbines. The daily flow calculations for the three sites (HPP1, HPP2 and HPP3) can be used in the hydropower calculations, and to assess the overall profitability of the planned investment, considering energy prices, demand, etc.

In the Nakra basin, glacier and snow model parameters were tuned to obtain accurate river flow predictions. Also, the latest technology of remote sensing data on precipitation and temperature (product ERA5) was used to reduce potential errors in flow estimates. Even though these flow estimates are useful for short-medium term evaluations on profitability of the planned investment, climate change pose a challenge for long-term evaluations. Glacier-fed and snow-fed systems, such as the Nakra basin, are driven by a complex combination of temperature and precipitation. Due to future increasing temperature, and changing rainfall patterns, glacier and snow cover dynamics change under climate warming. This can lead to shifts in the flows, like a reduction in lowest flows, and higher discharge peaks when the hydrological system shifts towards a more rainfall-runoff influenced system (Lutz et al. 2016). This can jeopardize the sustainability of the project on the long-term. To provide a better understanding of future river flows, it is recommended to develop a climate change impact assessment.

This hydrological assessment delivered river flow estimates for an intake location of a potential hydropower plant in the Lukhra river, Georgia. The assessment included a tuning of a hydrological model based on knowledge of neighboring basins, daily river discharge simulation for an extended period of record (1989-2019), and the derived flow duration curves and statistics to evaluate the flow operation of hydropower turbines. The daily flow calculations for the site can be used in the hydropower calculations, and to assess the overall profitability of the planned investment, considering energy prices, demand, etc.

In the Lukhra basin, snow model parameters were tuned to obtain accurate river flow predictions. Also, the latest technology of remote sensing data on precipitation and temperature (product ERA5-Land) was used to reduce potential errors in flow estimates. Even though these flow estimates are useful for short-medium term evaluations on profitability of the planned investment, climate change pose a challenge for long-term evaluations. Snow-fed systems, such as the Lukhra basin, are driven by a complex combination of temperature and precipitation. Due to future increasing temperature, and changing rainfall patterns, snow cover dynamics change under climate warming. This can lead to shifts in the flows, like a reduction in lowest flows, and higher discharge peaks when the hydrological system shifts towards a more rainfall-runoff influenced system (Lutz et al. 2016). This can jeopardize the sustainability of the project on the long-term. To provide a better understanding of future river flows, it is recommended to develop a climate change impact assessment.

The Paris Agreement requests each country to outline and communicate their post-2020 climate actions, known as their NDCs. These embody efforts by each country to reduce national emissions and adapt to the impacts of climate change. As ratifying parties, Armenia, Georgia and Uzbekistan must therefore outline how they intend to implement their NDCs and provide information on what the focus of this spending will be. To support this effort, the Asian Development Bank (ADB) is implementing a knowledge and support technical assistance cluster which will help enhance capacities of developing member countries (DMCs) in meeting their climate objectives by assisting in refining and translating nationally determined contributions (NDCs) into climate investment plans.

In this work package, ADB aims to support Georgia, Armenia, and Uzbekistan with the implementation of their NDCs through developing urban climate assessments (UCAs) and mainstreaming low carbon and climate resilience measures into urban planning processes. FutureWater contributed to this effort by supporting knowledge creation in relation to climate change and adaptation which will help each country to make more informed climate investment decisions.This was accomplished by conducting analysis of downscaled climate model ensembles for different climate change scenarios and synthesising data related to urban climate risk.

Climate change trend assessments were conducted using the NASA-NEX downscaled climate model ensemble combined with ERA-5 climate reanalysis products. To determine climate risk at the urban level, a number of openly available datasets were analysed and compiled using a spatial aggregation approach for 16 cities in the area. Results were presented as user-friendly climate risk profiles at the national and urban scales, allowing for insights into climate trends and risks over the coming century. These will be presented to non-expert decision makers to help support Armenia, Georgia and Uzbekistan develop targeted and informed NDCs.

The North–South Corridor serves as the main transport artery for the region, which spans quite diverse and spectacular terrains from the historic capital of Georgia, Mtskheta, up north to Stepantsminda in the Great Caucasus mountain range. The road experiences heavy traffic and is unsafe due to a design that is inadequate for the challenging geographical and climatic conditions, particularly in winter. The area is prone to avalanche, landslide, and snow load risks, which cause frequent and extended closures of the road. The two-lane highway provides a low standard alignment and is characterized by substandard open tunnels and avalanche galleries, in which modern trucks cannot pass simultaneously. An upgrade of the existing road alignment with improved geometry and avalanche galleries was considered but deemed inappropriate as it would not address the core climate-related risks.

Recognizing these challenges, the government has therefore requested ADB’s and EBRD’s assistance to improve the North–South Corridor. The climate-resilient project road will allow more traffic to travel on it safely and will remain fully operational all year. A detailed Climate Risk and Vulnerability Assessment (CRVA) report has been developed for the project road. The projected increase in extreme precipitation events is considered as the most important climate risk for the project road. This not only leads to higher extreme discharges, but can also lead to more frequent landslides, mudflows, and avalanches. The climate model analysis yields following conclusions for the project area:

Temperature increases by about 2 °C (RCP4.5) to 2.7 °C (RCP8.5) are to be expected
Minimum and maximum temperature are likely to change inconsistently, with maximum air temperatures increasing more than minimum air temperatures. This implies a larger diurnal temperature range for the future
Extremes related to temperatures (e.g. warm spells, extremely warm days) are likely to increase in frequency and intensity
Precipitation totals are likely to stay reasonable constant
Precipitation extremes are likely to increase in frequency and intensity. Maximum 1-day precipitation volumes with return periods of 25, 50 and 100 years are expected to increase by about 10% to 20%.

Stress tests were carried out by the project road design consultant team using +10% and +20% increased precipitation input for return periods used in the engineering design. These tests revealed that bridges have sufficient capacity in the current design to cope with higher discharge levels in the future, although it would be prudent to check the bridge substructure designs for higher flow velocities and the possibility of increased debris content in the flow. The tests indicated that a small proportion of the transversal and longitudinal drainage systems might have insufficient capacity to cope with the increased precipitation extremes. These should be identified, and their dimensions increased appropriately.

Due to its geographic location, Georgia’s role as a major transit country is significant. Transport of goods into and through Georgia has increased over the past 10-15 years. Almost two-thirds of goods in Georgia are transported by road but the roads are poorly equipped to cope with the volume of traffic and the proportion of heavy vehicles, and factors such as insufficient dual carriageways, routing through inhabited areas and inadequate maintenance and repair, hinder throughputs and increase transit times. The government of Georgia has therefore launched a program to upgrade the major roads of the country, including part of the East-West (E60) Highway. This climate risk and vulnerability assessment (CRVA) has examined the proposed components for section Shorapani-Argveta (F4) of the East-West Highway Road Project. The climate model analysis yields following conclusions:

Temperature increases by about 2.1 °C (RCP4.5) to 2.9 °C (RCP8.5) are to be expected
Minimum and maximum temperature are likely to change inconsistently, with maximum air temperatures increasing more than minimum air temperatures. This implies a larger diurnal temperature range for the future
Extremes related to temperatures (e.g. warm spells, extremely warm days) are likely to increase in frequency and intensity
Precipitation totals are likely to stay reasonable constant
Precipitation extremes are likely to increase in frequency and intensity. Maximum 1-day precipitation volumes with return periods of 25, 50 and 100 years are expected to increase by about 10% to 20%.

The increase in extreme precipitation events is considered as the most important climate risk for the project road. This may lead to higher extreme discharges that exceed the systems’ design capacity and cause flooding or inundation of road infrastructure. More extreme precipitation events can also lead to increased slope instability alongside the project road, causing more frequent and more powerful landslides, rockfalls and/or avalanches. In addition, the projected increase in diurnal temperature variability may lead to an increase in freeze–thaw conditions. This may result in deterioration of road pavement integrity, resulting in more frequent maintenance requirements. It can also further increase the risk of slope instability, making any stretch of road close to steep terrain more vulnerable to such mass movement phenomena.

According to the design team, the structures at risk of flooding (e.g. bridges, road sections) are sufficiently dimensioned to cope with return levels 10-20% higher than used in the original design calculations, which can be reasonably assumed. Retaining walls and mass movement protection structures are in place. The performance and sustainability of the pavement structure and structural joints may be adversely affected by the increase in the diurnal temperature range. To mitigate this risk, it advised to use road pavement with highest capability.

There is great potential for hydropower in Georgia, and this natural resource is likely to be increasingly utilised for power generation in the future. With the escalating demand for energy, government authorities are keen to harness renewable energy from the country’s main rivers. Often these projects aim at remote communities for which connecting to the national power grid is expensive. Hence, local hydropower production is an attractive and sometimes viable option. Critical is to conduct accurate feasibility assessments for hydropower generation at the different potential sites of interest considering climate change impacts. This work is a glacio-hydrological assessment of the expected river discharge at the planned hydropower sites in the Mestiachala river, Georgia.

Based on the requirements of the project, the Spatial Processes in Hydrology (SPHY) cryospheric-hydrological model was selected for the assignment. SPHY is a hydrological model that simulates the runoff at any location within the basin at a daily timescale. SHPY is ideal to assess glacier and snow influence in the river discharge and evaluate the impact of climate change. SPHY was used to predict the river discharge for the extended period of record and provide enhanced flow duration curves for hydropower assessment. In addition, total runoff components were quantified such as snow and glacier runoff.

This glacio-hydrological assessment delivered river discharge estimates for intake locations of two planned runoff river hydropower plants near Mestia, Georgia. The assessment included the calibration of a hydrological model, daily river discharge simulation for an extended period of record (1980-2015), climate change scenarios, and the derived flow duration curves to evaluate the flow operation of hydropower turbines. In addition, total runoff components were quantified such as snow and glacier runoff.

The daily river discharge was simulated at the two intake locations for two future periods (for the end of the concession period and for the end of century period) considering two climate change scenarios (RCP4.5 and RCP8.5). Hydrological model simulations were developed using future precipitation and temperature predictions and future glacier extent predictions. The climate change scenarios provide an evaluation of flow operation uncertainty. The daily flow calculations for the two sites can be used in the hydropower calculations, and to assess the overall profitability of the planned investment, taking into account energy prices, demand, etc.

There is interest to develop run-off river hydropower plants in a watershed in southwestern Georgia: a cascade of two projects of around 25 MW each. Before the actual development phase can start, a hydrological assessment is necessary to assess expected flows at the two locations with higher accuracy than currently available from limited flow measurements.

FutureWater was contracted by the developers to undertake an assessment of the expected daily flows at the two site locations , based on satellite data and hydrological modelling. Only very limited streamflow data were available, so the assessment was based mainly on hydrological modelling of the basin upstream of the points of interest. Principally global datasets were used for the input requirements of the hydrological modelling. Validation of the model was done using limited recent streamflow data available and satellite-based snowcover measurements. The principal output of the work are daily flows and a flow duration curve, based on model simulations. The flow duration curve includes confidence bounds based on the uncertainties that can be expected originating from data and model parameters.

From this hydrological assessment, a number of recommendations are put forward that aim at increasing the level of accuracy in the outcomes and narrow the uncertainty range for the following feasibility stage. Recommendations are done for data improvements, model improvements and field validation. Outcomes of this study will be used by the developer to analyse the hydropower potential and evaluate the economic feasibility.

There is great potential for hydropower in Georgia, and this natural resource is likely to be increasingly utilised for power generation in the future. With the escalating demand for energy, government authorities are keen to harness renewable energy from the country’s many rivers. Often these projects aim at remote communities for which connecting to the national power grid is prohibitively expensive. Thus, local hydropower production is an attractive and sometimes viable option. Critical is to conduct accurate feasibility assessments for hydropower generation at the different potential sites of interest.

This pre-feasibility assessment delivered daily flow estimates at several locations in Georgia, including an estimate of the level of uncertainty. This uncertainty was bounded by studying the parameter uncertainty in the model. The final accuracy level of this assessment is around 10% for the high flows, and 30% for the low flows. These flows were used as input into an economic analysis. If the economic analysis results in a positive outcome, the following-up feasibility study will further improve on the hydrological modelling, possibly using the more advanced model SPHY instead of HEC-HMS given its good performance in high-mountain areas.

Agriculture continues to be critical for poverty reduction, employment, economic growth and food security in Europe and Central Asia (ECA). Agricultural production, processing, and related services remain an important source of income in many ECA countries (approaching 30% of GDP in Central Asia). However, the agricultural sector is highly climate sensitive and potential adverse changes in temperature, precipitation and the frequency of extreme events as a result of climate change are likely to increase the vulnerability of poor rural communities. The World Bank’s ECA Region is working with client countries through an innovative regional, multi-year program of analytical and advisory activities (AAA) on reducing vulnerability to climate change in ECA agricultural systems.

This study contributes to the agriculture sector climate change impact assessment and adaptation and mitigation strategy identification and evaluation. The study encompasses the three countries of the Southern Caucasus region: Armenia, Azerbaijan, and Georgia. The project also includes components for capacity building among in-country staff, and support of the World Bank team’s awareness raising, communication, and dissemination goals for climate change.

Impact of climate change on wheat yield in Armenia based on Aquacrop in 2040-2050. Base = current situation; L, M, H are Low, Medium and High climate change scenarios

FutureWater undertakes the analysis using AquaCrop for the most important crops in the region. Impact assessment and potential adaptation strategies have been assessed. Capacity building and awareness rising have been an integrated component of the activities.