Climate Change, Groundwater Salinization and Road Maintenance Costs in Coastal Bangladesh

Abstract

The potentially-adverse impact of salinity on paved roads is well-established in the engineering literature. The problem seems destined to grow, as climate-related changes in sea level and riverine flows drive future increases in groundwater salinity. However, data scarcity has prevented systematic analysis for poor countries. This paper assesses the impact of groundwater salinity on road maintenance expenditures in the coastal region of Bangladesh. The assessment draws on new panel measures of salinity from 41 stations in coastal Bangladesh, and road maintenance expenditures, income, road network length, and road surfaces from 20 coastal municipalities. In a model relating maintenance expenditure for paved roads to groundwater salinity, municipal income, and road network length, large and significant effects are found for salinity. The regression model is used to predict the effect of within-sample salinity variation on road maintenance expenditure share, holding municipal income and road length constant at sample mean values. Increasing salinity from its sample minimum to its sample maximum increases the predicted road maintenance expenditure share by 252 percent. The implied welfare impact may also be substantial, particularly for poor households, if diversion of expenditures to road maintenance reduces support for community sanitation, health, and other infrastructure related programs.

Influence of surface geology and micro-scale land use on the shallow subsurface salinity in deltaic coastal areas: a case from southwest Bangladesh

“…This exploratory study indicated the importance of protecting enclosed polder areas from salt water flooding associated with storm surges as those can lead to widespread salinity of the soil leading to a decline in crop production ) and may also increase the cost of roads and infrastructure maintenance (Dasgupta et al 2014). It also indicates that the confining layer, separating the aquifer and the surface land-use actions, may slow down the process but would not be able to stop the salinisation.…”

“…Recent storm surges associated with these cyclones, such as Sidr in 2007 and Aila in 2009, have left a trail of destruction and inundated large areas with sea water in the southwest coastal region of Bangladesh (Kibria et al 2015). These inundations have resulted in widespread salinity problems in the area, including high soil salinities, which have led to a reduction in agricultural yield (Dasgupta et al 2015). Future rising sea levels coupled with embanked landscape and reduced up-stream flow (Mirza 1998) will most likely increase the area of inundation from similar surges (Bhuiyan and Dutta 2012;Dasgupta et al 2009;Karim and Mimura 2008;Singh 2002).…”

Effects of Soil Salinity on the Expression of Bt Toxin (Cry1Ac) and the Control Efficiency of Helicoverpa armigera in Field-Grown Transgenic Bt Cotton

“…Host plant nutrition can also modify the plant’s reaction to insects, which can have varied effects on herbivore densities [18,20]. Some studies have indicated that high temperatures [30–32], drought and waterlogging [37,22,34], nitrogen nutrition [47,48] and salinity stress [38–41] can affect the control efficiency and Bt protein content of transgenic Bt cotton. In this study, we focused on the influence of soil salinity on the Bt protein content and control efficiency of Bt cotton and the change in the pest population in the field during the growing season.…”

“…Other studies have examined salinity stress-induced changes in the control efficiency of Bt cotton against CBW [35,37]. However, the stress in controlled conditions from NaCl has certain differences from the natural saline stress encountered in the field [38–41]; thus, the results obtained in the laboratory may be subject to certain restrictions under real conditions for application to cotton production in practice. To discuss the responses of transgenic Bt cotton to soil salinity, the relationship between the salinity level, Bt protein content and control efficiency in transgenic cotton need to be investigated under field conditions.…”

Impact of Climate Change and Land Use on Groundwater Salinization in Southern Bangladesh—Implications for Other Asian Deltas

“…> 1000 mg/L) in drinking water (Rahman, 2014, Worland, et al, 2015 have been shown to be associated with prevalent hypertension (Scheelbeek, et al, 2017) -a risk factor for preeclampsia in pregnant women (Khan, et al, 2011, Khan, et al, 2014 and cardio-metabolic diseases in general, as well as increased rate of infant mortality . In addition, high groundwater salinity combined with raised water tables in coastal areas is causing increased maintenance costs for roads (Dasgupta, et al, 2014). Furthermore, as salinity in coastal surface waters increases, this is putting many freshwater ecosystems under threat (Herbert, et al, 2015).…”