পায়রা ব্রিজ সম্ভাব্যতা সমীক্ষার এক্সিকিউটিভ সার-সংক্ষেপ
OUT LINE OF THE PROJECT
Project site : Proposed Bridge Site is at17th km on Kachua- Betagi-Patuakhali-Lohalia-KalayaRoad(Z8052).
Bridge : Total length of the bridge is 1690m .The Main bridge and Viaduct are as follows; Main Bridge is 1000.0m long consist of segmental pre-stressed post tensioned box girder. Structural forms: 2×50+9×100 =1000.0m
Viaduct is 690.0m long consist of pre-stressed I section. Structural forms:11×30+12×30 =690.0m
Approach Road : Approx. 500.0m on each side
River Training Work (RTW) : River Bank protection works would be 100m upstream and 50m downstream of the bridge centre line on both sides of the river.
Project Cost : BDT 6895.48 Million.
Construction Period : 2014 to 2017 ( 4 years)
NPV : BDT 944.70Million BDT
BCR : 1.24
EIRR : 18.03%
Traffic Volume : Motorized Traffic 33,976 Veh /day at the Year 2047.
Indirect Benefit : Will increase the economic activity, educational activity and overall benefit of the region.
The purpose of the Executive Summary is to highlight the Major findings of various studies and the conclusions and recommendations of the study team.
The Notification of Award for providing Consultancy Services was issued by the Chief Engineer on 28 September 2011. The Consultant has started their work from October 2011.The Consultant submitted the reports as following table;
| Types of Report | Date of submission |
|---|---|
| Inception Report | 26 October 2011 |
| Interim Report | 29 February 2012 |
| Draft Final Report | 25 April 2012 |
| Draft Final Report Revised | 26 June 2012 |
Bangladesh is a country with innumerable rivers flowing across its territory. The Padma River is the mightiest of all these and ranks as the fifth largest river in the world in terms of volumetric discharge. The western part of deltaic Bangladesh is physically detached from northern and eastern part including capital city, until a massive bridge is built across the Padma River.
Ferry crossing at ferry locations which are the major tidal stream, considerably hampers road communication particularly during flood season. The proposed bridge at the ferry location will grossly improve the road communication. The bridge will also improve the socio-economic condition and industrial development of the area.Construction of Bridge At Pairkunja Ferry ghat (R870) on Kocha river
Description of the River
At the ferry ghat the name of the river is “payra” (Payra- Buriswar). The river width at the ferry ghat is about 2 km and the river is a tidal one with a reported tidal variation of +/- 2m. The Payra River originates from Pandab River in Kolskti Union of Bakerganj upazila of Barisal district. The river flowing down southwards by the side of Lebukhali, meets the Patuakhali river just at the upstream of the ferry ghat and the combined flow moves further down as Pyra river and crosses Amtoli of Barguna. The river is about 90km long. Its recorded depth at Amtoli was 20m in monsoon (in August) and 12.5m in winter( February). It moves further southwards and falls in the bay of Bengals as Burisshawr River.
Importance and justification of the proposed bridge at 17km on Kachua-Betagi-Patuakhali-Lohalia-Kalaya Road (Z8806)
The proposed bridge will give direct and uninterrupted connection with the Mirjaganj and Betagi upazila and the river will provide connectivity with Perojpur district and Khulna region with Patuakhali district after construction of bridge over Kocha River. After the construction of the Padma Bridge the traffic will increase manifold and it will be very difficult for the ferry service for carrying all the transports smoothly and timely.
The ferry service at present is giving connectivity with other places. But at ferry points we have to wait average one and half hour or more. If the bridge is constructed, the commercial vehicles will give more trips and working hour of people will be saved.
At the natural calamity the ferry services disrupts economic and social activities seriously. The Consultant found the construction of the bridge is economically viable. So construction of the bridge at the ferry location is justified
The two lanes cost of bridge is found to be BDT 6895.48 Million whereas the cost of four lane bridge will be BDT 13572.39 Million.
From above study based on traffic volume and cost of the bridge, it is seen that the construction of four lane bridge is neither justified from traffic point of view nor from construction cost.
- From traffic projection of total motorized traffic(Table 2.5.4, Volume – 1), it is found that AADT in the year 2047 is 33,976 veh / day (Normal traffic 13,512 nos, Diverted traffic 7,286 nos and generated traffic 11,134 nos) which is less than 35,000 the saturation capacity of two lane Bridge & 2 lane carriage way (Ref: ADB TA# 4821- BAN 2009).
- From traffic projection of total non-motorized traffic (Table 2.5.5, Volume-1 it is found that AADT in terms of PCU / hr. in the year 2047 is 63 PCU / hr. which is far less than 400 PCU / hr, the minimum requirement of provision of NMV lane according to the Roads & Highways Department rules.
- From the traffic survey, it may be concluded that the Bridge with both side approach road is feasible for 2-lane carriage way.
The following data and figures have been collected from field surveys:
– The river is a tidal one.
– High bank to high bank distance of the river along analysis option: 1377 m
– Average ground level on Patuakhali side: 1.64 mPWD
– Average ground level on Mirzaganj side: 2.93 mPWD
– RL of the river at bank full stage: 1.64 mPWD
– Cross section area of the river at bank full level: 13,057 m2
– Length of the proposed main bridge: 1000 m
– Length of the proposed viaduct: 690 m
– Observed lowest bed level of the river: (-) 9.21 m PWD
– Mean High Water Spring at Patuakhali (as per BIWTA Tide Table)= 2.907 m in CD = 2.907 – (3.785 – 2.889) = 2.011 mPWD
– Mean Low Water Spring at Patuakhali (as per BIWTA Tide Table) = 0.242 m in CD = 0. 242 – (3.785 – 2.889)= (-) 0.654 mPWD
Review and analyses of the prevailing hydrological and morphological environments of the proposed Mirzaganj Bridge area leads to the following conclusions and recommendations:
- Design high water level: 4.05 mPWD
- Design low water level: ( – ) 0.72 mPWD
- Regime width of the Payra River at bridge site: 736 m
- Anticipated maximum scour level at bridge pier: upto (-) 30.13 mPWD
- Bridge soffit level over navigable portion of the channel: 22.35 mPWD
- Minimum bridge span openings on navigable portion of the channel:76.22 m
- Bridge alignment: On or near morphological analysis option – 1
- River training and bank protection work
Observed lowest bed level of the river was at (-) 9.21 m PWD. Anticipated maximum scour level at bridge pier is upto (-) 30.13 mPWD and anticipated maximum scour level at bridge abutment is upto (-) 21.59 mPWD. As such bottom levels of bridge piers and abutments will have to go to a depth deeper than (-) 30.13 mPWD and (-) 21.59 mPWD respectively and the bridge site will require proper river training and bank protection.
River Training work
At the Bridge location site, the width of the river from bank to bank at the centreline of the proposed bridge is about 1377m. The proposed bridge has been designed for a span length of 1690m. Thus from spanning of the bridge, it is evident that the bridge abutment are located at a safe distance from the main river channel. The river will be flowing normally under the bridge and no specific guide bank is required for the bridge.
Length of the river banks to be protected from site inspection and morphological study at the proposed bridge site it is seen that both river bank at the bridge site are stable. However, river bank protection works would be done for a length of about 100 m upstream and 50m downstream of the bridge centreline on both side of the river.
The river banks could be protected by stone pitching or by concrete blocks or by growing vegetative cover. Concrete blocks are costly. For this reason the Consultant suggests stone pitching work for river training work.
This study has been conducted keeping in mind to collect information for river bank stability and/or shifting of river course, if any, in the vicinity of the probable bridge location. Available satellite maps of this area between the years 1990 to 2010, covering a period of 20 years has been collected and analyzed by super impositions of these maps on a single map. In the reconnaissance survey 8 nos. X-sections were taken from 3.0 km upstream and 3.0 km downstream from the existing Pairakunja ferry ghat. After two steps screening of all the section & from hydraulic considerations, the following 4 locations were considered
• Option -1: Along the existing alignment of Pairakunja ferry ghat. The river banks are stable, the side slopes of river bank are mild & no significant bank shifting has occurred during last 20 years. the Option-1 to locate the bridge along the existing roads connecting the existing Z8052 route will involve minimum additional land to be acquired for the bridge approach. In this alignment 1.5 hac land will needed to be acquired, 03 nos of household and 49 temporary structures will be affected. 300m approach road will be required.
• Option -2: The alignment is 150.0m U/S from Pairakunja Ferry ghat, where the river banks are stable the side slopes of river bank is mild & no significant bank shifting has occurred during last 20 years. In this alignment 2.8 hac. land will needed to be acquired and 27 nos. temporary structures will be affected. 400 m approach road will be required.
• Option 3: The alignment is 300m D/S from Pairakunja ferry ghat. Here the river bank is stable and no significant river bank shifting has occurred within 20 years. In this alignment 3.2 hac. land will needed to be acquired, 02 structures will be affected. 970m approach road will be required.
• Option 4: The alignment is 1.50 km D/S from Pairakunja Ferry ghat. Here the river bank is stable and no significant bank shifting occurred in twenty years. In this alignment 4.5 hac land will need to be acquired, 1 nos household and 02 nos structures will be affected. 3.8km approach road will be required.
Therefore, considering the above aspects, the Consultants feel that the Alignment along Option-1 would be the most suitable location for the bridge.
চেয়ারম্যান, বাসেক বোর্ড
মুহাম্মদ ফাওজুল কবির খান
মাননীয় উপদেষ্টা, সড়ক পরিবহন ও সেতু মন্ত্রণ...
কেন্দ্রীয় ই-সেবা
গুরুর্তপূর্ণ লিঙ্ক সমূহ
- BBA E-Ticketing
- BBA Document Archive
- সরকারি ক্রয় বাতায়ন
- সেতু বিভাগ
- সড়ক পরিবহন ও মহাসড়ক বিভাগ
- নিরাপদ খাদ্য বিষয়ক নির্দেশনা
- দুর্নীতি দমন কমিশন হটলাইন- ১০৬
জাতীয় সংগীত
সামাজিক যোগাযোগ
ইনোভেশন কর্নার
জরুরি হেল্পলাইন নম্বর
