1. Revival of Water Bodies and River System for Smart Dhaka City
Saiful Alam
Institute of Water Modeling

2. Major River spill/ Flood way around Dhaka
Extended Dhaka
Greater Dhaka is surrounded by three major Rivers. There are six rivers surrounding the Dhaka Watershed which receives spill from Major River.
Dhaka City
Source: IWM

3. Regional Surface Water Balances in low Flow months
Demand of water for various usages in Dhaka far exceeds the water resources availability
Dhaka is located in the North Central hydrologic region. Untreated industrial effluents and domestic sewage are polluting unregulated manner the river system and the water bodies in the region. About 80 percent of the textile industries, dying and leather industries are located within the Dhaka watershed where demand for various usages far exceeds the surface water resources availability and which least among the other regions.

4. Groundwater level trends in Dhaka
GW resources availability is fast depleting, not even sufficient to meet the domestic and agriculture demand. Usages of groundwater by Industries is extra burden
In NC region steep lowering due to upper thick clay layer. Recharge constrained due to upper thick clay layer and urbanization (Dhaka, Gazipur)

5. Tongi Khal-Balu River-Lakhya
Turag-Buriganga-Dhaleswari
Tongi Khal-Balu River-Lakhya
6 River Surrounds Dhaka
Dhaka city
Dhaka city
The surrounding rivers are classed into two systems – the Balu- Sitalakhya river system in the east and the Turag-Buriganga-Bangshi-Dhaleshwari river system in the west. The western part of Dhaka is flood protected from Turag-Buriganga-Dhaleswari system soon after 1988 flood, while eastern portion is still without flood protection.

6. Existing Pump Capacities is inadequate to combat Climate Change
Western Dhaka
Flood Protected
Existing
Pump stations
Eastern Dhaka,
Without Flood protection
Proposed
Pump stations
Existing Pump Capacities is inadequate to combat Climate Change
Permanent Pumping Station:
Kallyanpur: 20 m3/s
Dholaikhal: 22 m3/s
Goranchatbari: 22 m3/s
Semi-permanent Pumping Station:
Kamalapur
Rampura
Eastern Part: 124 km2
Western Part: 136 km2
Existing flood protection in the western part is equipped with embankment and five pump stations to drain out the excess rainfall runoff within the polder.
Eastern Dhaka relies on gravity drainage system based on khals and wetlands. The proposal for the implementation of flood protection in the eastern part is under discussion.

7. Drainage System Storm Sewer Line: 280 km Open Channel: 145 km
Box Culvert : 10.5 km
DCC tertiary Drains:
anticipated about 1,200 km
Lakes:
Gulshan, Banani, Dhanmondi, Uttara,
Hatiljil, Cresent Lake,
Permanent Pumping Station:
Kallyanpur: 20 m3/s
Dholaikhal: 22 m3/s
Goranchatbari: 22 m3/s
Semi-permanent Pumping Station:
Kamalapur
Rampura
In order to drain out the excess storm water runoff there are 280 km of storm sewer, 145 km khals/open channel.

8. Blockage of Drainage System
Blockage at outlet near Diabari
Illegal encroachment at Mohammadpur
In absence of an efficient solid waste collection system there is a practice of indiscriminate disposal of municipal solid wastes into khals. Apart from that encroachment of wetlands within the city causes water logging and drainage congestion situation almost during every monsoon seasons. Only 50% of the municipal solid waste is being collected by the city corporation
Obstruction of drainage outlet
Storm water outlet at Dholaikhal

9. Pollution Of River Industrial Waste Water Solid Waste Dumping
Waste from poultry and dairy farms
Oil Spill & Bilge Water
There are 19 primary discharge points to the rivers and at least 41 secondary discharge points within the city (IWM, 2007) that drain mixed effluent including untreated wastes from industrial units like tanneries, dying and bleaching units.

10. Present Land Use of Western and Eastern Dhaka

11. 2017 2008 Encroachment of Wetlands and Water Bodies
Other extremely unacceptable processes that are ongoing at present is that the natural drainage khals and wetlands are being encroached and filled up by different vested groups leading to serious possibility of flooding and regular drainage congestion.
Dhaka should have an integrated approach towards the preservation of rivers and water bodies in and around Dhaka.

12. Future Scenario (Planned Improvements?)
Water Bodies/Flood flow zone/ retention pond
Rajuk in the Dhaka Area Plan (DAP) has a plan to preserve only water bodies/flood zone/retention are in the eastern dhaka. But as per Dhaka Metropolitan Development Plan (DMDP) (SRO No law/97 dated 3rd August, 1997), DAP should include two type of flood flow zone a) Main flood zone; b) sub-flood zone.
According to DMDP, there are two categories of Flood Flow Zones: (i) Main Flood Flow and (ii) Sub-flood Flow Zone.

13. Urban and Rural Linkage: Proposed land use in Badda Thana
Land filling of DAP water bodies in Eastern Dhaka ( Badda Thana)
2004
Proposed
Main Land-uses
2004
Residential
30.6
Agriculture / Vacant Land
50.3
Water Body/flood flow zone/water retention area
13.5
Roads
2.0
Others
3.6
Main Land-uses
2004
2025
Residential
30.6
65.1
Agriculture / Vacant Land
50.3
1.7
Water Body/flood flow zone/water retention area
13.5
16.5
Roads
2.0
9.6
Others
3.6
7.1
Agriculture land reduced from 50.7% to 1,7 % in Badda Thana
Agriculture land reduced from 50.7% to 1,7 % in Badda Thana
Water bodies+ flood zone flow+ Retention pond comprises 16 % of which 14 % id water bodies + retention pond only 2% flood zone. Land filling of DAP water bodies in Eastern Dhaka ( Badda Thana)

14. Hatirjheel: An example of an Integrated Development and Water management In Dhaka
Scenic and Attractive
Hatirjheel is an unique example for the restoration of Water bodies reviving the multi functional aspect of water bodies.
Navigation and Water Sports
Hatirjeel can be integrated with other water bodies in western Dhaka to restore historical water transport and many others.
Strom water retentions Pond
Rajuk should look appropriately demarcate flood flow zoning. Present provision in DAP contradicts the provisions in Environmental Conservation Act and BWA2013

15. Water body restoration is needed to reduce flood damage
One study shows area of Water bodies in Dhaka nee to be expanded in order to protect Dhaka from frequent internal flooding under climate change
Water body restoration is needed to reduce flood damage
There is still potential for integrated development of water bodies in eastern Dhaka. A number of larger water bodies demarcated by DAP should be urgently be acquired and developed for multipurpose usages.

16. Thank you