PEOPLE'S REPUBLIC OF BANGLADESH
MINISTRY OF FISHERIES AND LIVESTOCK
FISHERIES RESEARCH INSTITUTE

REPORT NO 3 BRACKISHWATER AQUACULTURE RESEARCH STATION (BARS): DESIGN - PHASE 1 CONTENTS

MAY 1986

FAO/UNDP TA-PROJECT BGD 83-010

IDA/WB AGRICULTURAL RESEARCH II PROJECT

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FISHERIES RESEARCH INSTITUTE—BANGLADESH
FAO/UNDP TECHNICAL ASSISTANCE PROJECT BGD 83-010

Dr. Asadur Rahman,
Director FRI,
MYMENSINGH.

Ref. SARP/VZ 56, d.d. 19 May 1986.

Dear dr. Asadur Rahman,

Herewith I have the pleasure to present to you the third Technical Assistance report, concerned with the site selection and design of the Brackishwater Aquaculture Research Station in the Khulna region. This report covers the first phase of the work; it describes what activities have to be carried out before the second phase (final design phase) can start. When everything proceeds well, this second phase can commence in July 1986.

Yours sincerely,

	J.C.J. van Zon Teamleader

The distribution of this report no. 3 is as follows (with nr. of copies):

A total of 38 copies is printed.

All copy-holders received a copy of this letter.

CONTENTS

SUMMARY

1 INTRODUCTION

1.1 Background to project
1.2 Objectives for brackishwater aquaculture
1.3 The Brackishwater Aquaculture Research Station
1.4 Terms of Reference for the design phase

2 SITE SELECTION AND DEVELOPMENT OF DESIGN

2.1 Site and design requirements
2.2 Characteristics of the Khulna/Satkhira area
2.3 Site identification
2.4 Design development

3 IMPLEMENTATION

3.1 Current action required

3.1.1 General actions
3.1.2 Specific actions

3.2 Information needed for Phase 2
3.3 Phase 2

ANNEXES

LIST OF TABLES

Table 1 - Significance of brackishwater production
Table 2 - Operational objectives for BARS
Table 3 - Site selection criteria
Table 4 - Typical experimental routines
Table 5 - Staff requirements
Table 6 - Design recommendations

LIST OF FIGURES

Figure 1 - Seasonal events
Figure 2 - Tengramari site
Figure 3 - Design outline

LIST OF ANNEXES

Annex A - Budget allocation bars
Annex B - Background cost data: Bangladesh
Annex C - Climatic data, Khulna

SUMMARY

1. The present report comprises Phase 1 of the design development of the Brackishwater Aquaculture Research Station (BARS) of FRI. The report describes in short the status and potential of brackishwater aquaculture in Bangladesh and the role research can play in its further development. Operational objectives for BARS are identified, with their relative priorities.

2. Site and design criteria are listed, based on:

   • infrastructural needs of the research programmes envisaged;
   • physical and chemical requirements for construction and water management;

   • expected staff requirements.

3. General characteristics of the Khulna/Satkhira area are described and projected on the site criteria mentioned above.

4. The preliminary selected site at Tengramari is analyzed for its suitability for BARS. Although there are shortcomings with respect to general land level and freshwater supply, the site can in principle be considered suitable. A preliminary lay-out of facilities is presented and design recommendations are provided.

5. A list is drawn up of general and specific actions that have to be undertaken before Phase 2 of the design development can proceed. In Phase 2 the design work will be finalized, needed specifications will be prepared, and bills of quantities and tender documents will be drafted.

1 INTRODUCTION

1.1 Background to project

(01) The present report, describing phase 1 of the design development for the Brackishwater Aquaculture Research Station (BARS) of the Fisheries Research Institute (FRI) is one in a series under the UNDP/FAO executed Technical Assistance scheme to the IDA/World Bank funded Agricultural Research II Project, covering the 1984–1989 quin-quennium.

(02) The Fisheries Research Institute is being formed to rationalize and develop research resources in fisheries and aquaculture in Bangladesh, and will comprise at least three research centres:

• Freshwater Aquaculture Research Station (FARS), Mymensingh;
• Marine Fisheries and Mariculture Research Station (MFRS), Cox's Bazar;
• Brackishwater Aquaculture Research Station (BARS), Khulna.

These Research Stations will be operational units; work will be co-ordinated from the Headquarters in Mymensingh, from where also administrative supervision as well as special services (documentation, statistics) will be provided.

The system so developed would be expected to play a significant role in the planned expansion of fisheries and aquaculture production in Bangladesh over the next 20 years. It is also evisaged to ensure that fish and shellfish production retains its importance in terms of food supply and export earnings in the face of increasing competition for resources.

1.2 Objectives for brackishwater aquaculture

(03) The areas and yields of brackishwater aquaculture in Bangladesh are subject to some uncertainty, though recent reports appear to converge at about 40,000–50,000 ha, with a contribution of some 6,700–7,000 t/yr of production, the majority of which is relatively high value shrimp for export. Although representing only 1% of total production, its value is at least twice that of the mere value of fisheries and aquaculture production. According to these reports, several 100,000 ha of land would potentially be available for further development, thus contributing a significant amount to the growth of aquaculture production in the country (Table 1).

(04) At the same time, much of the growth in culture area takes place in land empoldered (or otherwise developed) for rice production, or previously used for salt production. There are potential areas of conflict in land use, adverse socio-economic effects, and many as yet unpredictable long-term ecological effects. There are thus important questions to be resolved in both the extent of brackishwater aquaculture development and the forms of agriculture to be developed for most rational resource use and most equitable economic yield.

Within the Fisheries Research Institute system being established in the present programme, brackishwater culture is thus being given first level priority (Table 1).

Table 1 - Significance of brackishwater production

1.3 The Brackishwater Aquaculture Research Station

(05) A considerable strengthening of resources in the brackishwater sector is being proposed through several programmes mainly involving:

• specific polder development for shrimp culture, providing subsector areas for individuals or groups;
• research on land-use interrelationships between shrimp, rice, animal and domestic production;
• the development of shrimp hatcheries to supplement wild sources;
• the establishment of demonstration centres, normally based on private sector farms.

These programmes will be predominantly in the Khulna District, but also in the Chittagong and Cox's Bazar areas.

(06) The establishment of the Brackishwater Aquaculture Research Station would be seen as complementary to these developments, and would be directed towards specific research activities, together with appropriate demonstration and extension functions. These are summarized in Table 2, and thus define the overall design objective of the Station. Further detailing of these functions/activities will be presented in the report of the Shrimp Specialist under the present TA-programme, to be issued in May 1986.

The available overall budget for development of the Station is shown in Annex A.

Table 2 - Operational objectives for BARS

* Following development of respective research areas

1.4 Terms of reference for the design phase

(07) The terms of reference for the work presented in this report are as follows:

1. Preparation of design criteria for ponds, structures, and other facilities for the Brackishwater Aquaculture Research Station (BARS) of FRI, based on the Research Plan and the site selection carried out by respectively the Shrimp Specialist and the Soil Specialist;
2. Preparation of layout of ponds and buildings and preparation of preliminary designs of ponds and hydraulic works, all in consultation with the shrimp specialist;
3. Preparation of specifications for earth movement;
4. Preparation of specifications for water treatment;
5. Reporting; a full technical report is to be submitted within two weeks after the end of the contract period; format will be discussed with the teamleader.

(08) In view of the timing of the project, it was agreed to carry the work out in two short phases:

• a first phase to assist with final site selection, to initiate local survey work and to provide initial outline design criteria;
• a second phase to collate survey data, to prepare final design specifications, and to assist with the preparation of tender documents.

(09) The first phase of the work commenced on April 28th 1986, and was completed on the 10th May. The present report covers this first phase of the work.

2 SITE SELECTION AND DEVELOPMENT OF DESIGN

2.1 Site and design requirements

(10) In some respects, site selection for BARS is one of the most difficult and yet important tasks. As brackishwater environments are essentially fluctuating, both seasonally and tidally, a research station must be capable of supporting a suitable range of environments while remaining representative of as wide as possible a range of potential production sites.

(11) The siting of the Station in the Khulna/Satkhira area defines to some extent the use of the shrimp/rice type system as opposed to the shrimp/salt system of the S.E. area of Bangladesh. However, the chosen area is representative of the area with the greatest longer-term potential, and is more truly brackish than that of the SE.

The original site selected for this development was at the Benerpota Agricultural Research Station of the Bangladesh Water Board. However, this site is no longer available, and an alternative site in the general area is required.

(12) The main criteria for selecting a brackishwater site are shown in Table 3. As it is not the primary task of this assignment to select the site, comparative evaluations of sites are not detailed; this will be done in the report of the Soil Specialist under the present TA-programme, expected to be issued in August 1986.

Table 3 - Site selection criteria

(13) The main experimental requirements of the site are described in Table 4. Overall, the site should be at typical elevations for the area, should be accessible to a tidally fluctuating water supply, but does not need to be extremely large in area. A suitable area of higher ground will be required for the establishment of buildings and services.

Table 4 - Typical experimental routines

(14) The overall staff requirements of the Station are defined in Table 5. This will possibly be supplemented as demonstration and extension functions are developed. These figures, in turn, define the accomodation needs for the Station.

Table 5 - Staff requirements

2.2 Characteristics of the Khulna/Satkhira area

(15) As with the rest of the country, pronounced seasonal changes occur through the monsoon cycle, and a complex and changing physical and ecological relationship occurs as a result of changing water supplies and salinities.

(16) Soils in the area are of typical deltaic type, being composed generally of moderately fertile silt clays and silt clay loams. There are three main categories (or mixtures thereof), viz:

• acid sulphate soils
• calcareous alluvia
• grey floodplain soils

The last category is by far the most common.

As the soils are little affected by problems of acidity and consequent low yields, organic matter and salinity are the dominant characteristics in most areas. In general, the shrimp culture areas are in the saline or semi-saline areas, with medium to medium-high land level. A range of soil association and land-use types is observed, though general patterns of land use are those of rice, rice/ shrimp or, in the S.E., salt/aquaculture. The most critical characteristic is salinity; generally summer rains are sufficient to wash out accumulated salinity from the aquaculture phase, but some areas experience reduced rice yields, reduced potential for animal grazing, and the killing off of local trees and food crops as a consequence of aquaculture (see Fig. 1).

(17) A further critical feature is that of siltation. The repeated filling and draining during aquaculture operations, and the settling out of sediment in the quiescent pond environment result in steady accumulation of sediment on the pond floor. While this can provide useful inputs of fertility, the long-term effect are to raise land level, to reduce the potential for water exchange and, in some cases, to increase further flooding and sedimentation.

Fig. 1 - Seasonal events

2.3 Site identification

(18) At present, a prime site has been identified from a shortlist of three or four sites, located at Tengramari on the new road between Khulna and Monghla, approximately 30 km south of Khulna.

This site is within an existing shrimp-growing area, is relatively low-lying, and fronts directly on to the Ichamati River, which connects the main Pusur and Monghla Rivers.

The site is in an area of mixed calcareous/non-calcareous soils of the Barisal-Domuria association, slightly saline (15 in the Soil Association key). Land-use is 7 in the land capability key: moderately saline, medium-high land.

(19) Approximately 20–25 ha of land is available, of which about 70% is normally flooded during high tides (and is currently used for shrimp culture), the remainder being relatively high level, which floods extremely rarely.

Details of the site are shown in Figure 2.

2.4 Design development

(20) A typical design outline for the site itself is shown in Figure 3. This is for illustration purposes only, as the final specifications have not yet been defined. The outline is based on the following fundamental criteria:

• provision of replicate ponds (9) of 0.5 ha;
• provision of flexibly operated pond areas sufficient for at least 27 × 0.1 ha ponds;
• provision of at least one large pond of irregular shape, typical of those in actual use;
• storage of fresh water;
• the use of raised fringe land areas for tree and crop production;
• provision of hatchery and nursery space.

Table 6 outlines the main site development recommendations.

Table 6 - Design recommendations

FIGURE 2-TENGRAMARI SITE

FIGURE 3-DESIGN OUTLINE

3 IMPLEMENTATION

3.1 Current action required

3.1.1 General actions

(21) The following general actions are required:

1. Final enquiry whether any better sites than TENGRAMARI are available, with respect to:

   • slightly higher level;
   • better services/access;
   • direct access to main open water, already embanked;
   • at least the same size;
   • similar access to Penaeus/Macrobrachium culture;

   • better freshwater supply.

2. Define alternative sites with which comparison can be made.

3. Establish as early as possible confirmation of access to and use of preferred site - assure TENGRAMARI.

4. Identify as soon as possible what specific tendering procedures (both for World Bank and Government requirements) must be adapted for:

   • survey work;
   • engineering design/supervision;

   • contracting.

5. Identify suitable operators, through tender of required:

   • survey work (select);
   • engineering design/supervision (check-list; if possible identify/ select);

   • contracting (preliminary identification).

6. Review, with relevant bodies, specific research objectives in order to confirm design requirements of the Research Station.

3.1.2 Specific actions

(22) The following specific actions are required:

1. Contact local area Water Development Board for details of:

   • local climate;
   • tidal and flood levels, tidal cycles, local tidal node data;

   • any future operations (e.g. water or flood controls, irrigation systems, dredging), which could affect the site.

2. Contact local/regional planning office, determine whether any developments are due which will adversely affect the site. Find out whether protection (e.g. through zoning laws or use designation) would be available to prevent unwanted developments such as processing plants discharging nearby, large intensive shrimp farms using the same water source, etc.

3. Contact Survey Department (or equivalent) to find out:

   • whether local data exist;

   • where the survey datum points are.

4. Contact Roads and Highways to find out:

   • what datum points they used for the bridge;

   • what soil strength/engineering quality information they obtained while building the road and the bridge.

5. Contact Public Works Department to obtain details of standard house designs and their current budgets. Collect also local building material costs, and m2; m3 (or equivalent) construction rates (see also Annex B).

6. Contact Soil Resources Development Authority to determine what local data exist.

7. Select (see 3.1.1) agents to carry out a topographical survey of the site, related to Survey Department datum points, and place preliminary boundary and reference markers on the site. The survey objectives would be:

   • define the area and fundamental features of the site;
   • define site levels, including transects of the water supply canals, profiles of main walls, embankments, ponds and built-up land;
   • estimate main quantities of materials required to be moved;

   • identify the lenghts and depths of the main site features, e.g. sluice gates, building foundations, embankments, walls, pond floors.

8. Establish and record local tidal cycle data through at least one lunar cycle, plus details on at least one neap-tide and one spring-tide cycle, and records of the local rise in water levels as flood conditions increase. These should be related to local survey datum levels and to those of the main tidal gauge station (Monghla?).

3.2 Information needed for Phase 2

(23) Before the start of the second phase of the design, the following information would be required:

• confirmation of acceptability of the site, and intention to use it. Also definition of longer-term site security;
• confirmation of research objectives and staff levels;
• clarification of tender procedures required;
• identification, or at least unofficial short-listing of design and supervision engineers, and scheduling of meetings;
• soils data, including strength data;
• tidal and flood level data: general from the Water Board, and specific from on-site measurements, relative to defined datum;
• topographical (area, level) survey of the site, relative to defined datum;
• local climate data, particularly rainfall/evaporation patterns (see example in Annex C).

(24) If, for any reason, this site is not available, similar information would be required of any other site, assuming, of course, that such a site met with the fundamental site selection criteria (Table 3).

3.3 Phase 2

(25) When the information mentioned in 3.2 comes available, the more specific design work of Phase 2 can be handled. The following procedures will be involved:

• precise specification of site and design criteria;
• development of preliminary designs; checking with budget;
• definition of final design; consultation with ‘user group’ and with local engineering team (or nominees);
• preparation of specifications;
• drafting of estimate bills of quantities and tender documents.

(26) The following drawings are likely to be produced:

1. site location, layout, building location;
2. site sections/elevations;
3. gate and wall details, pump installation;
4. water supply, power distribution;
5. building details;
6. water treatment systems.

ANNEXES

ANNEX A
BUDGET ALLOCATION FOR BARS

(Source: WB Staff Appraisal Report, 1984)

COSTS OF LOCAL ENGINEERING SERVICES (Tk × 1000)

Design and tender documents - 850 (2.2% of construction costs)
Supervision of construction - 1,350 (3.5%  "           "             " )

ANNEX B
BACKGROUND COST DATA: BANGLADESH

1. Exchange rates April/May 1986

₤ lUK = 45Tk.
$ 1US = 30Tk.

2. 282 ha project, 1980

3. 40 ha shrimp culture scheme, 1983/84

Yield: 138 kg/ha P. monodon, 23 kg/ha M. rosenbergii, 47 kg/ha finfish 49 kg/ha other (total 966,720 Tk/yr)

25 Years. NPV 2,019,759; IRR 114.53 %.

4. General price levels

ANNEX C
CLIMATIC DATA, KHULNA