Newsflash April 2018

 

Reaching the Millions

A deal for all stakeholders in global challenges: investing in the capture of rainfall at scale by:

  • The collection of runoff and floodwaters,
  • The retention and storage of this water,
  • Its use when required.

This is called the 3R approach. The return on investment comes in the form of reduced operational costs, disasters adverted, higher productivity, and healthier people and landscapes. The 3R book ‘Reaching the millions’ describes 8 thematic investment profiles to achieve impact through rainwater harvesting at scale. 3R. Recharge, Retain and Reuse of rainwater will avoid costly and multiple negative effects and at the same time create social and economic benefits contribution to multiple SDGs. 3R creates opportunities to connect finance streams in an innovative outcome payment model, create scale and impact for diverse investment. As taking no action on the world-wide water crisis is expensive, the consortium launched the trillion-dollar business deal. Want to know how 3R tackles this financial challenge with proven social and economic benefits? Download the 3R Deal book ‘Reaching the millions’ here.

 

Constructing roads in low-lying floodplains 

Roads, if built properly, will preserve and even enhance the different eco-systems services of floodplains. Development in low-lying floodplains presents a special challenge and opportunity at the same time as roads in these terrains have a major effect on the hydrology of the area – positive or negative. The new practical note on constructing roads in low-lying floodplains to optimize ecological and economic functions is discussing the opportunities and recommended practices in constructing roads in floodplains. It discusses recommended and preferred options related to location and height of embankments and controlled overflow sections; adequate cross drainage and subsurface flow capacity; culverts; French matrasses; cross drainage structures; and fish passages. On top of that, it gives recommendations on submergible roads which is an alternative road option in floodplains. Also, an annex is attached which gives clear design guidelines of floodway construction.

 

The power of drainage
 
Internal roads in polders change the natural drainage patterns and direction of flow in waterways. Roads determine the water distribution and availability inside polders and can also lead to water logging. Field surveys conducted in Polder 26 in Bangladesh show waterlogging as the main problem facing communities in the Polder. Farmers are facing crop loss up to 70% due to water logging as seeds are washed away. Aquaculture is adversely affected by the strong water current and salinization. Moreover, field surveys reveal that water crossings such as culverts are insufficient, under-dimensioned or in poor condition due to lack of maintenance. To begin with, polders were constructed without regulators to control water distribution and water levels for irrigation. On the other hand, farmers are facing water scarcity on higher grounds during the dry season. This is not only the case in polder 26 but also in The Amodkhali drainage Polder located in Polder 2 which has been accumulating silt for the past 15 years. This has significantly reduced its drainage capacity. See how the community got together to solve this problem in this short video.
 
Bangladesh University of Engineering and Technology (BUET) together with MetaMeta conducted a comprehensive hydrological model study based on field assessments in Polder 26. The hydrological modelling simulated several scenarios and determined optimal locations for new culverts, which were eventually validated with local representatives (Blue Gold, Water Management Groups, Local Government and local engineers-BWDB/LGED). Blue Gold funded the construction of 5 culverts and MetaMeta 2 culverts. The results show that improved drainage will decrease waterlogging significantly. Areas with high water levels decreased by 287%. Less inundated areas with lower water levels increased by 157%; thus, making more area available for agriculture. Moreover, the duration of drainage was also reduced by 10 days in the low-lying areas. If the problem of water logging is solved completely, farmers can practice multi-cropping, increasing agricultural productivity by 300%.
 
The results from the modelling exercise prove that roads can be turned into instruments of polder water management. Providing regulation structures at water crossings results in multiple benefits to the rural communities such as reduction in waterlogging, increase in agricultural productivity, creation of opportunities to diversify crops, improvement in communication and local livelihoods, as well as overall socio-economic development.

 

Harvesting Road Water

In southern Malawi, heavy downpours during the rainy season cause much damage to rural roads. This is largely due to lack of drainage along these roads. This situation can be turned on its head, by building structures that help not only drain the road runoff but also harvest it for use in irrigation and groundwater recharge. Roads for Water and the FBLN Malawi, are working together with farmers and officials to spread harvesting of road water in Malawi. See a video on this here.

In Kenya, Mrs. And Major Mwania reap fruits form road water harvesting in their own farm. Read the story here.

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