Module 9 – Water budget in concept

Module 9 – The Water Budget in Concept (Conceptual Water Budget)

“Natural watershed systems seek to maintain a balance between precipitation, infiltration (to the groundwater system), evaporation (from open water surfaces) and transpiration (from vegetation). This completes the cycle from the atmosphere to the land and back again. It is necessary to understand this “balance” or “water budget” in order to sustain the resource and its environmental and human interconnections within the watershed.”
– Water Budget Analysis on a Watershed Basis, Queen’s Printer for Ontario, 2000

Learning Expectations

By the end of this module you will:

Understand the hydrological cycle from a new perspective
Understand the meaning, purpose and local implications of a water budget
Demonstrate an understanding that a water budget is a tool to quantify water supply and demand and describe the movement and pathways of water
Understand the relationship of water quantity and water quality
Identify the water quantity pressures in the Maitland Valley and Ausable Bayfield source protection areas
Please visit sourcewaterinfo.on.ca for current assessment reports and source protection plans.

Section One – Module Content

Learning Expectations and Learning Activities to Achieve Expectations

Unit 1 – Understanding a Water Budget

Unit 2 – Water Budgets in the Ausable Bayfield Maitland Valley Source Protection Region

Chapter 3 of the Maitland Valley and Ausable Bayfield Assessment Reports is called Water Budget.

Chapter 2.3 of the Maitland Valley and Ausable Bayfield Assessment Reports is called Water Quality and Quantity.

Chapter 5 of the Maitland Valley and Ausable Bayfield Assessment Reports is called Potential Impacts from Climate Change.

Activity 1 – Group Activity – Title: Review of Session 8

Share thoughts in the ‘Parking Lot’

Review evaluations from previous session.

Did you know?

Activity 2 – Group Dialogue – Field Learning – Title: Conserving Water in Our Region

As a group take up your field learning assignment from last module and share:

a) Measures that could be taken to conserve water locally by individuals, or;

b) Measures that could be undertaken to conserve water by local government, or;

c) Water consideration measures which could be undertaken by sectors such as industry, agriculture, commerce, property owners, etc.

Did you know?

Unit 1 – Understanding a Water Budget

This is the first of two modules related to water quantity and the drinking water source protection planning tool, the ‘Water Budget.’ This first module
will address water quantity and water budget in more general terms while the subsequent module will look in more detail at the way a water budget could be used in this this Source Protection Region.

Activity 3 – Small Group Activity – ‘Round Table’ – Title: Water Quality and Water Quantity: Which is a bigger concern in our region?

Which is viewed as a greater concern in Ausable Bayfield Maitland Valley Source Protection Region – water quality or water quantity?

Have one person in a small group write down on a sheet of paper which they think is the biggest concern and why.

When the facilitator rings a bell (or turns on the music, etc.) pass the sheet to the person on your left.

Then, have them answer which they think is the biggest concern and why.

Share your group’s different answers with the larger group.

Activity 4 – Facilitated Group Dialogue – Title: Water Quantity Relationships

What is meant by “the solution to pollution is dilution”? Discuss.
What is untrue about that statement?
What is true about that statement?
Do we sometimes put a greater value on one or the other? Why?
What is the relationship between water quality and water quantity?

Activity 5 – Small Group Activity – Say and Switch – Title: How do water budgets and bank accounts compare?

In pairs, or small break-out group, discuss ways that water supply is like a bank account balance with credits and debits.

Then share with the larger group.

Using an egg timer or other device, have each member of the group try to explain how water supply is like a bank account balance.

When the sand runs out, have the next person share.

How is water supply like a bank account?
How is water supply different from a bank account?

Activity 6 – Personal Reflection – Title: Know Your Areas

Answer the following questions based on your own ideas about the planning region. When you are done, share with a partner or small group to see if you had the same ideas about the characteristics of the watersheds in this source protection region.

1) Characterize the planning region’s land use and landscapes. Is it?

a) Largely agricultural and rural

b) Agricultural and urban

c) Having large tracks of unaltered natural areas

d) Heavily developed in terms of aggregate industries

e) Heavily developed in forestry activities

2) The population is:

a) Growing slowly

b) Stagnant

c) Generally dispersed and of low density

d) Largely concentrated near surface water bodies

e) Poised to grow significantly

3) Our local quantity of water available for our use is:

a) Not at risk.

b) Not significantly at risk

c) Somewhat at risk

d) Significantly at risk

4) Where do people get their domestic water?

a) Municipal Lake Huron supply

b) Private or communal Lake Huron supply

c) Municipal well

d) Private well

e) All of the above

5) What are some of the water quantity pressures affecting you in your local watershed?

6) What are some processes that might affect the flow and availability of water?

Activity 7 – Presentation – Title: What is a water budget?

A water budget is …
A hammer is a tool to securely fasten substances together in order to make a construct.

A water budget is also a tool. It is a tool that:

a) _______________________________________________________

b) _______________________________________________________

c) _______________________________________________________

Why is the Water Budget used in the Water Quantity Risk Assessment Process?

Activity 8 Presentation – Title: The Power of Four

When looking at the Water Budget we can look at various aspects in groupings of four.

Based on the presentation, answer the following questions:

What are four major aspects of a water budget?

What are the four questions a water budget answers?

What are four factors in answering these questions?

What are four steps or in preparing the water budgeting process?

What are the four components of the water budgeting process?

What are the four main reasons to use the Water Budget as a tool?

Activity 9 – Small Group Activity – Title: Components and Processes of the Hydrologic Cycle

In a small break-out group you will be given cards with:

a) A ‘component’ of the hydrologic cycle (e.g., the atmosphere), or;

b) A ‘process’ (e.g., Climate-Soil-Moisture Budget).

Place the card in the category of Component or Process.

Then, define the components and processes.

Components and Processes of the Hydrologic Cycle

Component

Process

Definition

Unit 2 – Water Budgets in the Ausable Bayfield Maitland Valley Source Protection Region

Activity 10 – Presentation – Title: How do we use water budgets in our region?

Name five of the main watershed systems in our source protection region:

a) _________________________________________________

b) _________________________________________________

c) _________________________________________________

d) _________________________________________________

e) _________________________________________________

How much of the planning region do they drain? _____________ River system drains _ of the region. _____________ River system drains _ of the region. _____________ River system drains _ of the region. _____________ River system drains _ of the region. _____________ River system drains _ of the region.
At present the following communities or areas face water quantity (source or supply) risks:
How are water budgets used in the Ausable Bayfield Maitland Valley Source Protection Region?
How could a municipality use a water budget for quantification of water use?
What are the main uses of water in Ausable Bayfield Maitland Valley Source Protection Region?

Activity 11 – Small Group Activity – Three-Step Interview – Title: Sharing Water Quantity Thoughts

In a group of three people have one person be the interviewer, another person be the interviewee and a third person be the recorder.

One person asks the question.

Another person answers.

Another person records.

(Then switch roles if time permits).

What water quantity pressures affect our region?
What data gaps exist in terms of water budgeting information in Ausable Bayfield Maitland Valley Source Protection Region?

a) _________________________________________________

b) _________________________________________________

c) _________________________________________________

Activity 12 – Facilitated Group Dialogue – Title: Priorities

Using coloured markers, based on the multimedia presentation, colour-code the planning region based on areas where water supply issues are the largest priority and where they are the smallest priority.

_________________________________________________________

SECTION TWO – Priming the Pump

Notes, Definitions, Fact sheets

The Water Budget in Management and Protection of Drinking Water Sources

Water quality and quantity cannot be separated. Hence the saying, “Dilution is the solution to pollution.” While we can’t take that saying literally there are grains of truth in that old maxim (to a point).

As a society, we depend on protection of water quality and quantity for our personal and family health, and our economic health.

Chapter 3 of the Assessment Reports provides water quantity stress assessment which is based on a synopsis of the water budget reports (Conceptual, Tier 1, Tier 2).

Decreasing water availability is an increasing concern in our neighbouring North American countries (the United States and Mexico) as well as other parts of the world. Even in parts of Canada and Ontario water supply is a concern.

Locally, there are watersheds facing low precipitation or streamflow and conservation of water is required through municipal programs or watershed-wide low water response strategies.

The scientific community is warning of climate change and that too could affect our fresh water quantity.

This, in turn, has an effect on water quality and makes it even more crucial that we protect the supplies of clean water we do have.

Most areas in the Ausable Bayfield Maitland Valley Source Protection Region have relatively secure supplies of water. But some areas have more pressures than others. We don’t know the effect of climate and weather variability in the near future and low water in the Great Lakes and local rivers may be a trend, not just part of a cycle.

Water quantity remains a short-term concern for parts of our watershed, and a long-term concern for all our watersheds.

Water quality is the most important immediate concern in our study area but that can’t be divorced from water quantity – and we can’t take our relatively abundant supplies of water for granted.

The learning goal in Module 9 is to gain an understanding of the water budget as a technique in the management and protection of our supplies of water.

Today we are drinking the same water that Joseph Brant drank. Or before that, the same water that King Tut drank. And long, long, long before that, the same water that the dinosaurs drank. Mother Nature is not making any more.

Water is consumed and it reappears somewhere else. Water evaporates and then it condenses and vice versa. The location of water and its quantities change in any given location over time. But in a broad sense, there is always a balance. Water is taken out and water is replaced in equal measure. While balanced globally, regionally it can be moved and removed.

It helps to think of a water budget the way an accountant would. Debits and credits have to balance. Water’s balance sheet may be viewed the same way at least in the global sense – water removed in one place and will be replaced in equal measure elsewhere. The debits and credits will balance.

Of course there is one big difference between a balance sheet with dollar signs and a water budget especially when we narrow the study area from the global to the local. For a particular watershed, the water losses and gains do not necessarily balance. It is important for water resource managers to understand whether water is been taken out of the watershed and not replaced in full.

What is a Water Budget?

Water budgets involve understanding and characterizing the hydrologic cycle.

Major processes of the water cycle include evaporation, condensation, and precipitation. In a creek, river, or lake, when water (a liquid) turns to vapor
it evaporates. When a liquid’s surface changes to a gas, that’s evaporation.

The water budget is the term we use for the investigative process (concept or technique) which leads to a better understanding of the fluxes (flows or
changes) in water in and through a hydrologic system (its ‘components’ and ‘processes’).

Water budgets involve understanding and characterizing the hydrologic cycle, its various components and the processes.

A ‘Water Budget’ is all about more fully understanding the changes in water in and through a particular hydrologic system.

Looked at another way, the water budget is a tool that:
Quantifies water supply and demand, and;
Describes the movement of water (its pathways).

A ‘Water Budget’ is the methodology resource managers use to more fully understand the fluxes (flows or changes) in water in and through a particular hydrologic system (its components and processes).

Taking still another perspective, the Water Budget is used to manage the quantity of existing and future drinking water.

Finally, it is used in the Water Quality Risk Assessment process (remembering that water quantity can affect water quality).

Numeric water budgeting may be undertaken particularly where the users in the watershed rely on aquifer sources and:

In the event a major new water taker emerges (e.g., a new municipal system or a heavy industrial water user) and/or;

If there is evidence of new or increased stresses in the watershed.

Water budgets are being planned at this time and are important to:
Understand water quantity issues and the water budget process.
Appreciate that the current ‘stresses on quantity’ do not presently threaten sources or supply but there is a real potential threat to water quality from diminishing water quantities.
Gain new insights into the inter-connection between water quantity and water quality in the water budget process.

And, as always, it is one of our underlying goals to encourage you to become ‘champions’ for drinking water source protection and for the long term, the water budget is an integral aspect.

The Fours of Water Budgeting

Let’s look at some of the ‘fours’ of water budgeting:

Four Major Aspects of Water Budgeting

There are four major aspects of water budgeting:

The characterization of the surface water system (more specifically, examining the ‘sub-systems’ such as climate, infiltration etc.);
The groundwater system (the geology and hydrogeology and the characteristics of our aquifers);
The connections between the surface and groundwater systems, and;
Water use.

Four Main Questions Answered by a Water Budget

Simply, how is a water budget done?

The water budget answers four main questions:

Where is the water? (Where are the reservoirs, etc.?)
How does the water move between the reservoirs? (What are its pathways?)
What and where are the stresses on the water? (e.g., Where are the takings?)
What are the trends? (Is the quantity of water levelling, increasing,
constant?)

Four Factors to Answer Water Budget Questions

Getting more specific, what particular or key factors are considered when
answering these four questions?

There are four:

What quantities of water exist in the reservoirs of the hydrologic cycle (e.g., precipitation, evapotranspiration, runoff, groundwater inflow and outflow, change in storage, water withdrawals and water returns)?
What are the pathways of ground and surface water and what are the temporal, seasonal and annual changes in these pathways?
What are:

a) The key hydrologic processes (recharge and discharge areas), and;

b) The potential water sources (aquifers and unused surface water sources)?

Is there evidence of change in the cycle due to climate, land use, additional takings?

Four Steps in Preparing a Water Budget

Identifying the key components and processes of the hydrologic system.
Understanding the inter-connections of these components and processes, e.g., understanding water flows and pathways, and the fluxes of water between reservoirs.
Quantifying the fluxes.
Preparing the water budget.

Four Components of Water Budget Process

There are four components to the Water Budget process:

The atmosphere
The ground surface
The unsaturated zone, and;
The saturated zone.

Components of the Hydrologic Cycle

Here are components of the hydrologic cycle:

The atmosphere

The ground surface

The unsaturated zone

The saturated zone

Precipitation

Evapotranspiration

Flow

Infiltration/recharge

Runoff

Three Main Process of the Hydrologic Cycle

There are three main processes of the Hydrologic Cycle:

Evapotranspiration
Flow
Water-takings

Other processes are:
Atmosphere/climate/soil moisture budget
Surface Water – Quantity, quality and routing
Unsaturated zone water – Quantity, quality and routing
Saturated zone (Groundwater) – Quantity, quality and routing

Do we need to use a water budget here in this region?

You might ask the question, ‘Do we need a water budget in our drinking water source protection region?

Well, to answer that question, let’s look at your planning region:

The region has various municipal, industrial, agricultural, commercial, and recreational long-term users.

The population in the region has been historically low or flat.

It is generally dispersed.

There are populations beside water bodies but the communities are small numerically and in density.

Many communities are connected to Lake Huron water supplies, a source with ample growth potential.

During droughts, some agricultural areas or operations run low on supplies for irrigation or for livestock. Some municipalities apply water use restrictions.

These are temporary conditions. And the issue is supply not quantity at source or at alternative source.

At present no serious water quantity risks are apparent in most parts of the watershed – although there are isolated concerns and the future may be affected by projected climate change and climate variability.

Please visit sourcewaterinfo.on.ca for current information on water quantity threats.

Visit your local conservation authority website for any current low water advisories.

Another look at the purpose of the Water Budget

The purpose is of course already found in the definitions and descriptions above. However, again it will be helpful to get more specific – the Water Budget has a multi-fold purpose:

Purpose of a Water Budget

The purpose of a water budget is to:
Set quantitative hydrologic targets (water allocation, in-stream eco-system
flow requirements, recharge rates etc.)
Adjust established targets.
Help evaluate the cumulative effects of land and water use (connecting to
water quality risk assessment).
Provide a sub-watershed framework for site-scale studies (Sewage/Wastewater Treatment Plants [STPs], water supply plans).
Aid in designing environmental monitoring plans.
Set targets for water conservation.
Help establish long term water supply plans.
Identify data/knowledge gaps and to investigate climate change.

Components and Processes

The components, terms, reservoirs and processes of the water budget is best explained using a combination of diagrams and words.

Referring to a diagram as you go, note that the water budget team considers four compartments:
Atmosphere
Ground surface
Unsaturated zone
Saturated zone.

Precipitation falls onto the ground surface and then can:
Evapotranspire back to the atmosphere;
Runoff to surface water bodies (e.g. streams, lakes, wetlands), or;
Move down to the unsaturated zone.

Water that moves to the unsaturated zone can:
Evapotranspire back to the atmosphere;
Move laterally as interflow to discharge to local surface water bodies, or;
Move down to the saturated zone.

Water that moves to the saturated zone can:
Evapotranspire back to the atmosphere;
Move in the groundwater system and eventually discharge into a surface water body; or
Be removed for human purposes.

The diagram makes reference to complex vs. simple models.

Simple models are used in watersheds that are under minimal stress while complex models are applied where significant water takings occur in the watershed and/or where there are other stresses.

The aim is to determine human interventions in the water cycle including how and where water is recycled back into the watershed or whether the water is removed from the watershed.

The water budget, then:
Tracks changes and potential changes in water quantities and flows and using such knowledge,
Takes or recommends actions to maintain the ‘balance sheet’ whether that means protective or remedial measures.

The stresses that face our watersheds must differ from one area to the next.

Does this affect how a water budget is done?

Yes, a water budget team will elevate the data collection and analysis levels as need dictates.

Are water budgets a new analytical tool?

They are comparatively new. It is largely been since the 1990s that the Province of Ontario and a number of conservation authorities have developed this tool and prepared water budgets.

Despite its short history, the tool has evolved in scope. Originally a water budget was defined only as the quantification of the accounting of the
components of the hydrologic cycle (for a study area).

Under drinking water source protection planning, the meaning now includes the characterization or understanding (through modeling) of water flow paths in the watershed.

What areas require water budgets in the Ausable Bayfield Maitland Valley Source Protection Region and how were these areas selected?

An area is selected for a water budget based on qualities or characteristics common throughout the area. In other words, the analyst defines a ‘uniform area’ based on common:
Physiography and/or geology,
Land use,
Water use.

For the Ausable Bayfield Maitland Valley (ABMV) Source Protection Region, there is little difference from one area to the next in land use or water use.
However, there are physiographic differences and these are accounted for in the region’s sub-watersheds for which data (e.g., on infiltration, slopes) and programs (e.g., flood forecasting) already exist.

Accordingly, in the future the subwatersheds are to be used as the geographic basis for doing water budgets.

Associated Terms

Aquifer

An underground formation of permeable rock or loose material, which when tapped by a well can yield useful quantities of water.

Discharge

Discharge, with reference to stream flow, is the quantity of water that passes a given point in a unit of time. It can be measured in cubic metres per second or cubic feet per second (CFS). [Source: Leet, L. Don. 1982. Physical Geology, 6th Edition. Englewood Cliffs, NJ: Prentice-Hall.] can also refer to groundwater discharge – that is, water that is being discharged out of aquifers in the surface water system.

Recharge

Recharge is, according to the Dictionary of Mining, Mineral and Related Terms,

a. The processes by which water is absorbed and added to the zone of saturation, either directly into an aquifer or indirectly by way of another formation; also, the quantity of water so added.

b. Putting water brought from elsewhere into a body of groundwater to augment groundwater supply.

Groundwater

Groundwater is subsurface water occurring below the water table in fully saturated soils and geological formations.

Groundwater is:
Present almost everywhere underground.
Found in the spaces between particles of rock and soil, in crevices and cracks in rock.
Usually within 100 metres of the surface, however, in the Ausable Bayfield
Maitland Valley region groundwater tends be located 30 metres under the
surface on average

Groundwater flow

Groundwater flow varies in the rate of flow from slow to slower. (Sometimes it is relatively fast in limestone geology).

Interflow

Interflow is the runoff infiltrating into the surface soil and moving toward streams as shallow, perched ground water above the main groundwater level.

Water table

Water table is the level below which the soil and geological formations (all the spaces) are filled with water.

Saturated zone

The area below the water table and the water in this zone is called groundwater.

Unsaturated zone

The unsaturated zone is the area above the water table.

For more terms related to a Water Budget, refer to glossary page or visit abca.ca and sourcewaterinfo.on.ca.

Understanding water budgeting will guide us in water use and provide us with the information necessary to decide where water budgets are necessary.

Water quantity issues in Ausable Bayfield and Maitland Valley watersheds may one day join water quality on the front burner. Conservation practices can play a role in making that unnecessary. Water quality has been identified as a greater issue in this planning region than water quantity – however, there are still areas of the watersheds where water quantity is a concern and water quantity is always intrinsically linked to water quality.

SECTION THREE

Handouts, Additional Readings, Field Learning Assignments, Findings

Field Learning

Use the space provided here to provide your observations on what the documentary film An Inconvenient Truth, or a more recent film with a climate change theme, has to say about potential environmental impacts of climate change and share what implications climate change may have on water quantity.

Please consult climate change considerations in source protection plans and assessment reports at sourcewaterinfo.on.ca.

Self-Assessment on Learning Goals

We are approaching the last leg of the 15-module program in drinking water source protection and, in that last leg, learning participants will concentrate their efforts on providing feedback and input to the Source Protection Committee.

Which statement applies to you?
I have sufficient background knowledge to provide meaningful comment.
I have ample information but I need guidance to focus on the key issues.
I need to clarify and/or confirm my understanding/information. I need to know more about the following topics.

Your Evaluation of This Session

How do you rate this session?

How interesting was the material to you?

(Please circle the one that best describes your perspective).

Not interesting at all Not very interesting No opinion Interesting
Very interesting

How involved did you feel?

Not at all involved Not very involved No opinion Somewhat involved Very involved

What parts of the session did you think were weak?

What parts of the session did you think were strong?

Group Performance Goals

How well did this group achieve its goals this session?

Group Goal Achievement

How well was this goal achieved?

(Please circle one)

Write goal here: