44167-015: Flood and Riverbank Erosion Risk Management
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Environmental Impact Assessment (draft) Project No.: 44167-015 August 2020 (2 of 2) Bangladesh: Flood and Riverbank Erosion Risk Management Investment Program – Project 2 Prepared by the Bangladesh Water Development Board for the Asian Development Bank. This environmental impact assessment is a document of the borrower. The views expressed herein do not necessarily represent those of ADB's Board of Directors, Management, or staff, and may be preliminary in nature. Your attention is directed to the “terms of use” section on ADB’s website. In preparing any country program or strategy, financing any project, or by making any designation of or reference to a particular territory or geographic area in this document, the Asian Development Bank does not intend to make any judgments as to the legal or other status of any territory or area. August 2020 page i 10 ANALYSIS OF ALTERNATIVES 368. The three sub-reaches selected for Project-2 of the FRERMIP physical works: JRB-1, JLB-2 and PBL-1, were chosen from 13 sub-reaches into which the FRERMIP program area was divided based on discussions among BWDB, ADB and the PPTA consultant. These 13 sub-reaches were evaluated using a multi-criteria assessment approach taking into consideration three primary criteria (riverbank erosion, flooding, and poverty) and several secondary criteria (related to planning, design, cost-benefit and safeguards issues). Of the six sub-reaches scoring highest1, these three sub-reaches were screened out due to a lack of active erosion and/or conflicts with other immediately planned interventions. 369. While riverbank protection was placed according to immediate needs especially for growth centers (“something to defend”), embankment construction considered alternatives especially for the area JLB-2. BWDB contemplates the establishment of polders (ring- embankments) covering large parts of JLB-2 with very long ring embankment lines. These were compared to the solution of an embankment only along the riverbanks of the main rivers, reducing the length of the embankments and as such minimizing the footprint and related land acquisition and resettlement. In addition, open distributaries would allow all-year-round water flow to the area, which specifically enhances the dry season water management 2. 370. As such various alternative interventions have been considered. One of these has been large-scale Capital Dredging for which a national feasibility study was conducted (2010-2015). However, large-scale capital dredging on the one hand, and riverbank protection on the other, are different solutions to the same problem, and it is neither logical nor cost-efficient to implement both on a large scale simultaneously. Large-scale dredging is believed not be sustainable due to (continued) high costs and the high sediment load of river waters (resulting in rapid refill), and is therefore not further considered as a viable scenario under the present river stabilization planning process. However, limited dredging of river sections may be considered to stimulate the development of a desired future river planform with more stable river channels and a narrower active river corridor by the river itself, whereby dredged material is placed at selected locations in the floodplain and on chars. 10.1 Without-Project scenarios 371. Without JRB-1. It is expected that without additional riverbank protection along JRB-1, the embankment and important infrastructure in the Enayetpur area will remain vulnerable and the goal of the project will not be achieved. 372. Without JLB-2. The future geometry of the two downstream Jamuna branches fully depends on the discharge distribution at the bifurcation. Without countermeasures (stabilization works) there is a risk that the bifurcation changes over time with increased discharge in the right channel and reduced in the left one or vice versa. Other changes could happen within the channel pattern, for example the cut-off channel at Chauhali could develop and change the downstream channel pattern. As a consequence of these changes, the downstream channel pattern would change in two ways: riverbank erosion would take place in yet unprotected 1 The highest ranking sites scored between 300 and 370 points, while the lower ranking sites ranged between 200 and 260 points. 2 Annex D of the feasibility study, “River and Charland Morphology and River Engineering” provides more background. July 2020 page 1 reaches, and existing work to stabilize the downstream channel might turn out to be ineffective as placed in the wrong location. July 2020 page 2 11 ENVIRONMENTAL MANAGEMENT PLAN 373. In previous chapters, the possible positive and negative impacts have been identified and evaluated. In addition to that, mitigation measures have been mentioned to address adverse impacts. This chapter presents the Environmental Management Plan (EMP) prepared by the study team. The EMP entails mitigation measures for the negative impacts, enhancement measures for the positive impacts, compensation for the non-mitigated impacts and contingency measures for the accidental events that might occur. 374. The EMP has been organized per construction and post-construction phase (operation and maintenance), to facilitate the monitoring process. Impacts and mitigation measures broadly cover the three topics: (i) construction, (ii) biodiversity and (iii) fisheries and aquaculture. Most construction related impacts are mitigated by contractors during construction. Issues pertaining to biodiversity and fisheries/aquaculture, especially related to the construction of the embankment at JRB-1 will be implemented through a specialist firm/NGO, following the principles established by the biodiversity program of GIZ at Pabna, now extended to Sirajganj, and as part of the livelihood program of the resettlement plan. In addition, fisheries/aquaculture will be supported to compensate for the loss of open water fisheries on the floodplain after the construction of the embankments. Fisheries and aquaculture have a strong relevance for the poor and is part of the livelihood component of the resettlement plan, which is a separate compensation mechanism. 375. The layout of the EMP is as follows: Construction phase Site offices Riverbank protection Embankment construction Drainage structures/regulators-cum-fish passes Post construction phase per site Decommissioning Water resources Land resources Agricultural resources Fisheries resources Ecological resources Socio-economic resources 376. In addition to mitigating direct impacts of the ongoing Tranche-1 and planned Project-2 works, a specialist firm/NGO may be retained to elaborate on the biodiversity baseline and study the establishment of fisheries sanctuaries, in accordance with future stabilization plans, looking beyond the localized Tranche-1 and Project-2 measures and aiming at identifying and mitigating any impacts from larger scale river-reach stabilization. 377. Note that mitigation of impacts on local community members and their livelihoods are addressed via the Resettlement Action Plan. July 2020 page 3 11.1 Construction Phase for Each Site 11.1.1 Site offices, labour sheds, stockyards, etc. IESC Location Impacts Mag. Of Mitigation / Magn. Type of EMP cost Responsible impact* Enhancement / with Impact (Lakh Tk) Agency Compensation / EMP* Contingency Activity Construction of site office, labour shed(s) with proper water and sanitation facilities, garbage disposal system, stock yard and construction camp(s), materials, equipment and other machines, construction of cc blocks at site Air quality River and Minor impact may -2 Mitigation: -1 Short N/A Implementation: roadsides occur from dust Construction materials Term Contractor generated due to should be covered with Monitoring: movement of vehicles thick materials (i.e. Nominated Engineer polythene) during (SMO, BWDB) transportation to resist the generation of dust. Water to be sprinkled to control the generation and spreading of dust; as and where required. Noise Same as Low impacts caused -2 Mitigation: -1 Short N/a Same as above above due to noise Working hours to be Term generation for restricted to 8 h to 17 h mobilization of only; construction materials Noise levels due to and construction of vehicular movement are site office, labour to be kept within shed, stockyard and permissible limit; CC blocks Construction camps, office, labour shed, and sites for CC block construction are to be located sufficiently away from settlements. July 2020 page 4 IESC Location Impacts Mag. Of Mitigation / Magn. Type of EMP cost Responsible impact* Enhancement / with Impact (Lakh Tk) Agency Compensation / EMP* Contingency Land loss Same as Loss of 200 ha of 0 Construction activities +1 Short No cost or Implementation: above existing land should be carried out as Term cost for land Deputy per design. due to Commissioner, Sites should preferably activities on specialist NGO be constructed on fallow site Monitoring: PMO or khas land. Landowners affected by the construction of sites on agriculture land should be noticed ahead of time so that the area might not be affected for growing crops. Labour sheds, and other project related activities should be optimized with the purpose of minimum disruption to cultivable lands and standing crops. Adequate cash compensation should be provided to the land- owners /share croppers. The compensation should be determined based on the amount of land temporarily going out of cultivation. Health and Same as Unsanitary and -4 Proper sanitary facilities -1 Short Contractor Implementation: