The document discusses fluvial morphology, including definitions, scope, and importance, emphasizing its relevance to river management and environmental studies. It categorizes channel patterns—straight, braided, and meandering—and details their characteristics, along with examples from rivers like the Yamuna and Tista. Additionally, it outlines flood types, causes, impacts, and sedimentation processes crucial for delta formation and water resource management.

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Mohammad Mohaiminul Islam
Geography & Environmental Studies
University of Chittagong

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FLUVIAL MORPHOLOGY
Fluvial morphology definition: It derives from fluvious (river) and morphology (study of
structure).
Newson and Sear (1998) define fluvial geomorphology as- the science that seeks to investigate
the complexity of behaviour of river channels at a range of scales from cross sections to
catchments; it also seeks to investigate the range of processes and responses over a very long
timescale but usually within the most recent climatic cycle.
Graf (1988) defined- Geomorphology is the study of Earth surface forms and processes; fluvial
phenomena those related to running water.
Kruska and Lamarra (1973) defined as- Fluvial geomorphology has as its object of study not
only individual channels but also the entire drainage system.
The Scope of Fluvial Morphology:
In Present time, there are many portions of fluvial geomorphology for more transparency and
analysis is used in the world. There are some fluvial geomorphologic objectives are given below-
1. Qualitative fluvial geomorphology
 River system
 Catchments area
 Water flow flood management
 River features
 Flood control etc.
2. Quantitative Fluvial Geomorphology:
 Water Technology
 Water Quality treatment
 Stream discharge
 Changing nature of river
 Quantitative analysis of river depth, width, length etc.
Some particular scopes and objectives of Fluvial Geomorphology which are found in modern
period are given bellow-
 River channels and drainage basin
 River Management System
 Channel types
 Flood plains and terraces
 Bank full flow
 Types of river
Importance of fluvial morphology:
According to USGS, an understanding of river- and stream-channel geomorphic responses to
various human-caused and natural disturbances is important for effective management,
conservation, and rehabilitation of rivers and streams to accommodate multiple, often conflicting,
needs. Channel changes may have implications for the protection of property and structures, water
supply, navigation, and habitat. The channel-bank erosion that accompanies natural channel

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migration on a flood plain represents a constant threat to property and structures located in or
near the channel. Various human-caused and natural disturbances introduce additional instability
to which rivers and streams adjust. Human-caused disturbances include reservoirs,
channelization, in-channel sand and gravel extraction, and urbanization. A common natural
disturbance is a flood. Possible geomorphic responses of a channel to disturbances include
channel-bed degradation (erosion), channel-bed aggradation (deposition of material), channel
widening, and channel straightening. These adjustments represent the channel’s attempt to
establish a new approximate equilibrium condition.
Origin of fluvial morphology: Geography>physical/human; physical>geomorphology/fluvial
morphology.

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STREAM CHANNEL PATTERN
Channel Pattern:
 Leopold and Wolman (1957): By channel pattern is meant the configuration of a river as
it would appear from an airplane.
 R.J. Chorley (1971) in ‘Introduction to Fluvial Process’: This is a trace of a channel in a
plane as shown on instance on vertical air photography or as represented on map.
Types of channel pattern:
1. Straight channel and channel pattern
2. Braided channel and channel pattern
3. Meandering channel and channel pattern
i. Straight channel pattern: Straight channels are seldom straight for long distance and
there is usually an implication of the effect of initially steep slopes on homogenous rocks
(Leopold et al. 1964).
ii. Braided channel pattern: Braided channel is the one that has developed in several
channels that successfully meet and re-divided (Leopold et al., 1964). Braided river consist
of two or more channel divided by bars or islands, lead one channel being dominated
(David, 1984). For example, Yamuna River.

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iii. Meandering channel pattern: A bend or curve in the course of river is called a meanders.
River will bend by any kind of obstacles such as hard rock or pebble. Larger river has larger
meanders and vice versa.
Characteristics of channel patterns:
1. Straight Channel:
i. Rare in nature
ii. Surrounded by hard rocks (so it can’t bend)
iii. It has steep slope mostly.
iv. It is not straight for a long distance.
v. Flows in straight and twisted sections.
vi. Featured by rapid, waterfall and rock bands.
2. Braided Channel:
i. Sediment deposited at the river mouth.
ii. River becomes shallower for depositions.
iii. Creates estuary or islands that divides the flow into multiple sections.
iv. It is wider and shallower.
v. Stable but course changing.
vi. Sediment loads are heterogeneous materials (e.g. gravel, bolder coarse
grained, fine grained etc.)
vii. Higher channel velocity in main channel.
viii. Equilibrium in degradation and aggradation.
ix. Frequent river bed erosion.

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3. Meandering channel:
i. River winds from side to side.
ii. River flows over loose silt and clay.
iii. The banks are fairly stable.
iv. The river starts to wind due to irregularities in the channel.
v. Lateral shifting takes place.
vi. Fastest flow speeds occur on the outer bank resulting in erosion
vii. Slowest flow occurs on the inner bank slope resulting in deposition
Identification of Yamuna River Pattern: Yamuna is the sub-basin of the Ganga river system. It
is the largest tributary of the River Ganga. Considering its characteristics, it can be concluded that
it falls under the ‘braided channel pattern’ of stream channel pattern classification. The following
characteristics can be comprehended for the identification.
Identification Characteristics:
 According to Sharma and Kansal (2013), The Yamuna river is dissected at 5 barrages
during its course i.e. at Dak Patthar (near Uttaranchal); at Hathnikund (near Haryana); at
Wazirabad (near Delhi), at Okhla (near Delhi); and at Mathura (near Uttarpradesh). It has
other barrages and small rocky formation too.
Apart from that, in Bangladesh, the Yamuna River has several barrages and islands at
Manikganj, Tangail, Jamalpur etc.
This is basic feature of a braided channel according to Leopold et al. (1964).
 There are several sub-flow of Yamuna such as- Chambal, Sind, Betwa, Ken, Hindan, Rind,
Senger, Varuna etc. Having sub-flow is a feature of braided river channel according to
David (1984).
 According to Chaudhary (2016), there is sedimentation and TOC (total carbonic organ) in
the Yamuna river that influences the river depth to become shallower. It’s also a feature of
braided river channel.
From the above characteristics mentioned by different authors, it can be concluded that the
Yamuna River is a braided river channel.
Identification of Tista River with Characteristics:
Tista River an important river of the northern region of Bangladesh. It enters Bangladesh at the
Kharibari border of Nilphamari district. It is connected with Yamuna.
This river falls under the category of straight channel pattern due to the following features-
i. This river flows from Chatnai to Niphamari, Rangpur and Gaibandha and
meets with Yamuna River; in this flowing way, it almost remains straight but
twisted at some areas. This is the feature of a straight channel.

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ii. Tista river has carved out ravines and gorges in Sikkim meandering;
consequently it is surrounded by rocky band formed near ravines and
meanderings; which is a feature of straight channel.
iii. Due to the existence of gorges (canyon) it has steep slopes at some points; it
is also an important feature of straight channel.
From the above characteristics mentioned by different authors, it can be concluded that the Tista
River is a straight river channel.
Fig: Tista and Yamuna
Drainage Pattern: According to the University of Wisconsin, A drainage basin is any area of
land where precipitation collects and drains off into a common outlet, such as into a river, bay, or
other body of water. Drainage patterns are configuration of drainage basin formed by the streams,
rivers and lakes in a particular drainage basin. They are governed by the topography of the land
whether a particular region is dominated by hard or soft rocks and gradient of land.
Difference between Drainage Pattern and Channel Pattern:
Topic Channel Pattern Drainage Pattern
Definition Configuration of a river or stream channel. Configuration of drainage basin.
Area
Association
Not associated with particular area. Can be
defined with any unrelated channel.
Associated with area that has a
common precipitation outlet point.
Types Braided, straight, meandering etc. Dendritic, parallel, Radial, Annular,
Anastomotic, centripetal etc.
Outlet It does not have single outlet. It has a single outlet.
Division It meets with branches and divides. Does not divide.
Branches Has branches called tributaries. Does not have tributaries.
Accumulation Sometimes, channels work as a unit of
drainage pattern.
Several channels can be accumulated
in a drainage pattern.

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Channel Process: A river has the potential both to scour material from its bed and banks and to
transport material which has been brought into the reach from upstream and accumulate them at
some points as well; altogether these processes are called channel process. A river has 3 types of
channel processes; transportation, erosion, deposition.
Types of erosional feature: River can erode by mechanical and chemical process. Erosional work
of a river consist of various activities. Those are-
 Picking up the load
 Transportation of the load
 Along the river bed
 In solution (within the river)
 In suspension (above the river)
 Gradation
 Pebble grounding
 Mechanical
 Vertical (down cutting)
 Lateral (side cutting)
 Chemical
Some other features:
 Abrasion (rubbing of materials)
 Hydraulic Action (due to hydraulic energy)
 Corrosion (acidified dissolving of particles)
 Attrition (reduction of material size)
Erosional Landform: Valleys, canyon, gorge, waterfall, rapid, v shape/u shape valley etc.
Consequences of River Bank Erosion in Bangladesh:
Impacts of River Bank Erosion:
 Social Impact (Homelessness, Migration, Identity Crisis)
 Economic Impact (Loss of Productive Land, Loss of Employment, Risk of Poverty)
 Other Impact (Health Damage, Criminal Activities, Building Collapse)
River Bank Erosion Losses in Bangladesh:
 It is estimated that about 5% of the total FLOODPLAIN of Bangladesh is directly affected
by erosion.
 Bank erosion is taking place in about 94 upazilas of the country.
 At present, bank erosion and FLOOD hazards in nearly 100 upazilas have become almost
a regular feature. Of these, 35 are severely affected.
 Building sloping down due to river bank erosion.
Vulnerable Rivers: According to Banglapedia, The following rivers are vulnerable for bank
erosion.
• Jamuna
• Ganga
• Padma
• Brahmaputra

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FLOOD
Definition of flood: A flood is an overflow of water that submerges land that is usually dry. The
European Union (EU) Floods Directive defines a flood as a covering by water of land not normally
covered by water. According to Oxford dictionary of geography, flood occurs when peak discharge
exceeds channel capacity.
Types of Flood:
1. Flash flood (a sudden local flood, typically due to heavy rain.)
2. Monsoon flood (due to monsoon wind and raining)
3. Tidal flood in coastal region (temporary inundation of low-lying area during exceptionally
high tide events, such as at full and new moons)
4. Storm surge flood in coastal area (a rising of the sea as a result of wind and atmospheric
pressure changes associated with a storm)
5. Urban flood (the inundation of land or property in a built environment, particularly in
more densely populated areas, caused by rainfall overwhelming the capacity of drainage
systems)
6. Manmade flood (frozen pipes, damaged sewerage system etc.)
Causes of flood:
1. Climatic Cause
i. Rapid action of depression
ii. High rainfall intensity
iii. Excess runoff in drainage basin due to heavy rainfall
iv. Excess flow in river due to ice melting
2. Geomorphological Cause
i. Simultaneous runoff in main rivers
ii. Slope
iii. Low land
iv. Drainage pattern
v. Relief
3. Geological Cause
i. Earthquake
ii. Low gradient of river
iii. Point bars development in river channel
iv. Delta formation on estuary
4. Marine (Oceanic) Cause
i. Sea level change
ii. Storm surge
iii. Tidal surge
iv. Cyclonic effect
v. Tsunami backwater effect
5. Manmade Cause
i. Deforestation

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ii. Construction of river dam
iii. Construction of water reservoir
6. Hydrological Cause
i. Soil moisture level
ii. Shallow ground water
iii. Surface infiltration rate
iv. Presence of impermeable cover
v. Subsurface and open channel
vi. Morphometry of channel network
Consequences of flood:
1. Primary effect
i. Death and injury of people
ii. Damage and destruction of infrastructure
iii. Loss of livestock, damage of crops, fisheries and irrigation project
iv. Damage of vegetation coverage
2. Secondary effect
i. Homelessness
ii. Hunger
iii. Waterborne diseases
iv. Infectious diseases
Flood Mitigation Process:
1. Structural flood mitigation
i. Infrastructure, including dams, levees, bridges and culverts
ii. Maintenance of existing infrastructure
iii. Individual flood proofing measures
iv. Improved traffic access
2. Non-structural flood mitigation
i. Property surveys
ii. Land use planning controls
iii. Building and development controls
iv. Catchment flood modelling
v. Early warning systems
vi. Develop a household emergency plan
vii. Access to information and warnings
viii. Understanding and awareness
Benefit of flood:
1. Carry nutrient for soil
2. Increase soil fertility
3. Organism relocation and improved ecology
4. Provide necessary infiltration to water table

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5. Recharge and Replenish Ground Water
6. Prevent Erosion and Maintaining Land Mass Elevation
7. Renewal of Wetlands
Importance of flood creating floodplain:
 Flood creates land overflow.
 Land overflow leaves small bended channel of river when it gets back to the catchment.
 Meander creates this way.
 Meander becomes oxbow lake with sedimentation.
 Oxbow lake becomes filled with further sedimentation and creates floodplain.

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SEDIMENT LOAD
Sediment load: Sediment load means the sediment carried by the river, ice or sea (Phillip, 2003).
Load may be in solution, suspension or along the river bed.
Classification of load:
1. Dissolved load: Carried in the solution of river rather than the river bed. Proportion varies
according to the chemical properties of the rock.
2. Solid debris load: Debris is the fragmented materials from the rock or inorganic materials.
They are carried within the river through rolling, bouncing and sliding.
1. Suspended solid:
 Transported at some distance from the bed (R.J. Russell, 2003).
 Carried by both laminar and turbulate flow.
 200 tons/mile in a year in earth’s surface.
2. Bed Solid:
 Particle transported close to the bed (R.J. Russell, 2003).
 The coarser the particles are, the more energy flow required.
Delta: According to Oxford dictionary of geography, delta us a low lying area found at the mouth
of a river and formed of deposits of alluvium/silt.
Role of sedimentation in delta formation: When a river reaches a lake or the sea the water slows
down and loses the power to carry sediment Larry. The sediment is dropped at the mouth of the
river. Some rivers drop so much sediment that waves and tides can't carry it all away. It builds up
in layers forming a delta. Some deltas are so large that people can live on them. The Nile delta is
a very important farming area in Egypt.
According to Syvitski et al. (1988), there are four processes of sedimentation that influences the
delta formation procedures. E.g.-
(1) Bed load dumping at the river mouth, the main transition point for hydraulic conditions.
(2) Sedimentation under the seaward flowing river plume that carries the suspended load.
(3) Sediment bypassing processes, such as turbidity currents, that are a result of delta-foreset
failure.
(4) Diffusion processes, such as tides, waves, creep, and small slides, that work to smear
sediment downslope.
Delta formation Process:
1. Progressing forward advancing process
2. Aggradation and degradation process
3. Transgressing process
Transportation influencing factors:
1. Speed of water
2. Volume of water
3. Stream depth
4. Material type

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HYDRAULIC GEOMETRY
Hydraulic geometry: An expression introduced by Leopold and Maddock (1953) to describe
the hydraulic characteristics of stream channel. Mean velocity, mean depth and mean width of
flowing water are considered to be the function of discharge at given time and space.
There are equations related hydraulic geometry.
According to Oxford dictionary of geography, hydraulic geometry is the study of
interrelationship exhibited along the course of a river.
Parameters of Hydraulic geometry: a. velocity b. depth c. width
 v= kQm
 d= cQf
 w= aQb
Here,
v=mean velocity
d=mean depth
Q=discharge
w=mean width
a/m/c/f/b=numerical coefficient
Variables Hydraulic geometry: 10 variables under 3 categories according to Leopold and
Maddock (1953).
 Independent:
1. Discharge
2. Sediment load
3. Ultimate base level
 Semi dependent:
1. Velocity
2. Depth
3. Width
4. Bed roughness
5. Channel habit (pattern)
6. Grain size of sediment load
 Dependent:
1. Slope

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WATER RESOURCE MANAGEMENT
WATER RESOURCE MANAGEMENT: Water resource management is the activity of
planning, developing, distributing and managing the optimum use of water resources. It is a sub-
set of water cycle management. Ideally, water resource management planning has regard to all the
competing demands for water and seeks to allocate water on an equitable basis to satisfy all uses
and demands. As with other resource management, this is rarely possible in practice.
PROSPECTS OF WATER RESOURCE MANAGEMENT:
1. Improving agricultural water use efficiencies
Prospects in Development of Ground Water Resources-
• Due to lack of sufficient knowledge of irrigation scheduling and the threat of non-availability of
irrigation water at the right time, farmers rarely plan their irrigations in advance or attempt to
coincide them with critical periods of crop need.
• Where hose piping is not used, water is usually delivered through unlined irrigation channels to
fields that are poorly levelled.
• The additional pumping required as a consequence of inefficient application also involves
increased energy and financial costs for pump owners.
2. Balancing aquifer recharge and discharge
Prospects in Development of Ground Water Resources The emergence of groundwater challenges
poses two very major challenges to the State.
• First, the performance of currently operational surface water supply systems needs to be
improved.
• Secondly, groundwater will have to be managed – for related reasons of quantity and quality –
much more aggressively than has been the case in the past.
3. Diversifying cropping patterns
• In Bangladesh’s main boro growing areas, more than 90% of irrigation water is supplied through
groundwater.
• Maize is another potential alternative crop to boro rice. Wheat and maize both need very little
water (300 to 500 mm) to meet their evapotranspiration demand, especially when they are grown
after the rice crop.
• A significant water requirement of these crops can be met through the excessive moisture present
in the root zone from the previous rice crop especially if the strip or zero tillage method is used.
4. Revisiting groundwater governance policies
• Encouraging low water demanding high value crop in the NW region. Particularly in Rajshahi,
where GWT is declining rapidly.
• An estimated water budget should be prepared considering recharging, extraction rates and
change in the aquifer(s).
• Managed Aquifer Recharge should be undertaken as a national programmed and strategy
considering different regional contexts.

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• Local planners should consider recharge areas when making land use planning decisions that
could reduce recharge or pose a risk to groundwater quality.
• Irrigation water price should be determined as a rule on volumetric basis in order to meet equity,
efficiency and economic principles
• Modern water management technology like alternate wetting and drying (AWD), water saving
technology, climate change adaptive technology would bear no value without carrying out
irrigation volumetrically
• National Sustainable Development Strategies by the government is a good effort to achieve
sustainability in all developmental activities
• Awareness campaign and advocacy on sustainable water management concepts
5. Groundwater consumption for irrigation
• The increased availability of equipment led to the maturation of Bangladesh’s mechanized
agricultural economy.
• The leap in the population of STWs was linked their suitability to the prevailing socioeconomic
conditions of Bangladesh’s growing boro rice.
• The temporal development of DTWs, STWs, and LLPs in Bangladesh is shown in Figure 4.
Currently, about 79% of the total cultivated area is irrigated by groundwater, whereas the
remaining is irrigated by surface water (BADC 2013).
PROBLEMS OF WATER RESOURCE MANAGEMENT:
1. Declining water tables due to groundwater overdraft
Challenges in Development of Ground Water Resources. The substantial drawdown of aquifers
due to over-exploitation of groundwater during the last decade has been widely documented (Jahan
et al. 2010; Shahid 2011). Using data from the Bangladesh Water Development Board (BWDB),
we have determined that in areas with water tables less than 8 m in depth, decline has increased
significantly over time. Between 1998–2002, this area was only ~4% of the country’s total, but
increased to 11% in 2008 and 14% in 2012. The most significantly affected areas lie in the north-
west (e.g., Braind Tract) and north-central (i.e., Madhupur Tract) regions.
2. Groundwater - Energy Nexus for Bangladesh
• Groundwater irrigation requires large amounts of energy to lift water from underlying aquifers.
• In 2012, about 49 billion kwh of electricity was generated in Bangladesh, and about 2% of this
total generation was used to pump groundwater for irrigation.
• The subsidized cost of this electricity is about USD 50 million.
• Increasing power cuts and the generally poor electricity network in many rural areas comprise
other potential reasons for farmers’ diesel pump preferences.
3. Arsenic contamination of groundwater: 61 out of 64 districts are effected.
4. Changes in Wetland areas during the dry period: 300 sq. km area decreased.

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5. Water shortage due to the duration of the monsoon
• The availability of surface water is not consistent because of seasonal variation. Ninety-five per
cent of the surface water in the river system also originates outside the country (Ahmad et al.
2001).
• Bangladesh experiences a tropical monsoon climate with significant variations in rainfall and
temperature. Average annual rainfall varies from 1,200 mm in the extreme west to over 4,000mm
in the northeast.
• Therefore there is a seasonal water shortage depending on the duration of the monsoon.

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HYDROGRAPH
Hydrograph: Hydrograph is defined in Oxford dictionary of geography as- a graph of discharge,
or a level of water in a river throughout a period of time.
In hydrograph, x axis is used for plotting the time while y axis for discharge, runoff, infiltration or
precipitation.
Example:
Time (days) Flow(m3) Time (days) Flow(m3)
14 411 20 100
15 358 21 83
16 250 22 70
17 192 23 58
18 151 24 49
19 122 25 41
Hydrograph equation:
Q=Qo Kr
(t-to)
Here,
Q= discharge at t time
Qo= discharge at to time
Kr= recession constant
Application/use of hydrograph:
According to J.R. Reddy, there are following applications of hydrograph.
1. Development of flood hydrograph (for storm design, for hydraulic structure)
2. Watershed simulation model
3. Flood forecasting and flood warning
4. Flood flow records and rainfall records
Apart from that, it is used for measuring runoff and other discharges and showing their
relationships with time.
0
50
100
150
200
250
300
350
400
450
14 15 16 17 18 19 20 21 22 23 24 25
Flow(cubicmeter)
Time (days)
Hydrograph

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REYNOLDS NUMBER
The Reynolds Number is defined as the ratio of inertial forces to viscous forces and consequently
quantifies the relative importance of these two types of forces for given flow conditions. In a word,
a dimensionless number used in fluid mechanics to indicate whether fluid flow past a body or in a
duct is steady (laminar) or turbulent. It’s given by Reynolds in 1883.
Factors of Reynolds number: According to Oxford dictionary of geography, there are 4 factors
to determine whether the flow of a channel within a channel is turbulent or laminar. These are-
1. Density of water
2. Velocity of water
3. Viscosity of water
4. Hydraulic radius of the channel
Equation of Reynolds number: According to S. Mayhew’s (1995) description of Reynolds
equation, the equation is expressed as follows-
Re =
𝑉𝑅
𝜇
Here,
Re= Reynolds number
V= Velocity of liquid
R= Hydraulic radius
µ= Viscosity of liquid
Use of Reynolds number:
1. For dynamic analysis of fluid
2. For determining whether a flow is laminar or turbulent.
3. High Reynolds number indicate turbulent, which indicates the instability and chaos.

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FROUDE NUMBER
The Froude Number is a dimensionless term to describe the flow condition of a stream.
According to Oxford dictionary of geography it is the ratio of viscosity and celerity; where celerity
is a product of gravity and mean depth of flow. Given by Froude in 1861.
Factors of Froude number:
1. Viscosity
2. Celerity
3. Gravity
4. Depth
Equation of Froude number: The equation is described by Oxford dictionary as follows-
𝐹𝑟 =
𝑣
√(𝑔𝑑)
Here,
Fr= Froude number, with a value of less than 1
v= viscosity of fluid
g= gravity
d= mean depth of the fluid
Application of Froude number:
1. Determines the resistance faced by objects while flowing in the fluid.
2. Compares object sizes within the fluid.
3. Describes flow condition.

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ORIGIN AND DEVELOPMENT OF RIVER:
Geologic history of river origin and evolution:
 Water originated 4-5 BY ago in Archaean period.
 Water/hydrosphere created from gas emission from mantle/core.
 Water concentrated in glaciers, seas, rivers and lakes.
 Volcanic and tectonic process created terrestrial hydrosphere.
 Hydrographic network created among sea/lake/river etc. due to climatic effect.
 Glacier period started 115 KY ago and intensive ice melting started 15-16 KY ago.
 River system enriched in these time but affected by great change in Holocene period
(7000 Y ago). The current river system is the formation occurred from Holocene period
mostly.
Basic formation and evolution process of a river:
A river can have more than one source. Some rivers begin where a natural spring releases water
from underground. The source of the River Thames is a spring. Some rivers begin in mountains or
hills, where rain water or snowmelt collects and forms small channels. Then it faces young (high
erosion), mature (stable) and old (degradation) stage.
Tributary and distributary:
Tributary is a stream or river that flows into a larger stream or main river or a lake. A tributary
does not flow directly into a sea or ocean. It’s a small branches of large river, several tributaries
meet a large river.
Example: Tista, Korotoa, Dhoroloa, Atrai (they meet Yamuna)
Distributary is a stream that branches off and flows away from a main stream channel. In other
word, it’s a river created from another river and does not flow back to the origination
consequently.
Example: Kapotakhkho, Madhumati, Mathabhanga are originated from Padma.