6. Determining monitoring objectives appropriate to project risk and scale

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6.1 Monitoring approach

The primary aim of a monitoring plan is to measure the success of the project in relation to its objectives. How success is measured, including the scope, scale and intensity of monitoring, is determined by:

  • Project objectives: what needs to be measured, and at what temporal and spatial scale.
  • Catchment objectives: how is the project contributing to addressing catchment issues and achieving wider ambitions.
  • Resources: what funding is available and what capacity do stakeholders have to deliver a monitoring plan.

Project objectives primarily determine the elements that require measurement and the scale that they should be measured at. For example, the project objective "Increase number of fish species in the catchment within 5 years" dictates that fish need to be measured at the catchment scale for 5 years. Catchment objectives provide context for projects and highlight their significance in relation to wider plans which can influence the desired scope and intensity of the monitoring programme, and help to prioritise monitoring resources. For example, a showcase project that will promote river restoration to stakeholders and generate support for the delivery the wider catchment plan may warrant high resource priority. Resources, both financial and human, often dictate the realistic scope and intensity of a monitoring programme. Where ample resources are available, best practice monitoring methods should be employed in detail, however the reality is that limited funding requires the allocation of resources and a compromise on the approach in many cases.

Working through the sections below will help you decide whether your monitoring resources may be better used to fund small scale, low cost appraisal undertaken by a local community group or fishing trust, or instead should be used in conjunction with other resources to fund a highly scientific study. In some cases this may mean that the ideal monitoring program is not affordable, but the process will help to determine which elements to priorities.

6.2 What does the literature tell us?

An extensive assessment of the available scientific literature is included in Appendix 3.

Figure 6.1: Diagram showing the main steps for achieving monitoring and analysis of a river restoration project (adapted from Roni 2005)

The benefit of river restoration (including connection to the floodplain), needs to be assessed over both the short and long term to determine the degree of success. Ideally monitoring should be carried out before and after the project implementation for both the affected reach (i.e. the reach where the restoration work was carried out) and a control reach (i.e. one where no work was carried out and one which is also not affected directly or indirectly by the works). In order to carry out such an assessment a combination of qualitative and/or quantitative monitoring needs to be included. Determining the appropriate mix oof techniques (i.e. where to concentrate effort) requires a clear set of objectives.

It is clear from the literature that river restoration and rehabilitation work generally lacks the evidence to demonstrate ecological and hydro-morphological benefit, thus the development of technology and techniques has rather outpaced the supporting science. Most of the evidence is based in the USA where much river restoration began. What monitoring there is, most commonly focuses on the physical changes of the river rather than identifying specific biological effects.

Figure 6.2: Flow Diagram of the Restoration Process Adapted from Lydia Bruce-Burgess’s PhD Thesis (2004)

In general, monitoring is not the norm for enhancement and rehabilitation projects, resulting in a very limited pool of information from which to draw conclusions. Where monitoring is undertaken, appraisal is often hampered by a lack of clarity on desired project outcomes. The complexity in ecological response and the variability in measurable ecosystem components need to be carefully considered when setting up monitoring protocols. Selection of positive control sites is it important, and it has generally been suggested that restoration monitoring is best targeted at demonstrating the formation of different features through natural processes. These features and processes may support various habitats – it is preferable to focus on these rather than any specific habitat. The latter rarely demonstrates restoration benefit at a chosen monitoring site unless very a specific formation is met at that point. Under a dynamic river system, this is unlikely to occur.


A question of scale The spatial extent and time of monitoring must be determined on a case-by-case basis, and depends on the elements being measured. The spatial extent of data collection in highly variable systems may require comprehensive coverage and there is a need to pay close attention to the wider context when planning monitoring.


How to proceed? Beyond practical requirements for adaptive management and feedback to the design of projects and techniques, funding mechanisms and policy drivers increasingly require demonstration of success. Guidance on river restoration monitoring is limited, and the current document (PRAGMO) builds on the frameworks developed by Mant and Janes (2008) and England et al. (2008) to provide practitioners with the wide-ranging expertise needed to deliver river restoration monitoring.

6.2.1 Non-academic cited information

There are a number of articles which refer to river restoration monitoring but are not necessarily cited in academic literature. These provide a valuable source of information. This type of evidence is often referred to as „grey‟ literature and these sources are listed in the references Section 12.2 under a separate heading.

6.2.2 Effective monitoring

River restoration monitoring needs to demonstrate that project objectives have been achieved. Thus, SMART objectives must be set early on in the project as discussed in Roni (2005). The monitoring results can then be analysed to increase the evidence base for restoration schemes and help determine which techniques are most successful, where, and for which objectives. In addition, continuous monitoring can identify where projects may need future adaptation under specific environmental conditions, which makes up an element that is generally referred to as Adaptive Management (see Appendix 2, for further explanation and Figure 3.1 below).

Significantly:

To appraise river restoration projects, SMART objectives should be set at the scoping (or preliminary) phase and these must be appropriate for project aspirations.

Objectives at this stage will help to define success criteria and provide a clear indication of financial and staff time commitment.


It is at this stage that crucial baseline monitoring should be collected and/or collated from existing data sets if they exist in a form that is likely to answer project objective(s).

The detail of the monitoring strategy is defined in conjunction with the detailed design phase and before construction so that monitoring can be implemented concurrently.

A clear decision about the amount of project appraisal appropriate in the early stages, should result in more effective post project monitoring to increase the evidence base of project success or failure, and identify the need for minor technical adjustments through adaptive management or updated technical design.

6.3 Resource prioritisation for monitoring

The steps below explain an approach to resource prioritisation for monitoring to maximise the lessons learnt from projects and mitigate the risks of failure. The main principles are that a) more uncertainty about project success requires more detailed monitoring; and b) larger scale works require more detailed monitoring plans. These principles encourage a better understanding of success and failure so that lessons can be learnt for future projects.

The results of these steps may be overridden by the following conditions which should result in a higher priority and a more detailed approach to monitoring:

  • The availability of students or researchers to undertake detailed studies. Contact your local academic institutions to see if there are any opportunities.
  • Large project budgets which allow for detailed, long-term monitoring programmes.
  • Projects that are a crucial part of achieving catchment aims and objectives (e.g. demonstration or showcase projects).

6.3.1 Determining risk of failure

There are two elements of risk to consider: the degree to which the technique has been tried and tested, and its physical robustness. Both of these depend on the particular catchment and channel setting.

Brush wood in a stream

Previous application

Table 6.1 evaluates the frequency of use of a particular technique on your river, or one very similar, together with a more global measure of how well it has been tested. For example, narrowing a channel using brush wood structures is frequently used, with proven success, on chalk streams, but using the same technique on an over-wide higher energy river has been done much more rarely. Similarly, marginal planting is widely employed, but is far more common on lower altitude clay rivers than flashy cobble bed streams, as are measures such as the creation and reconnection of ponds, lakes and wetlands in the floodplain.

Thus:

  • Brush wood on a chalk stream would score 1 (frequent used in that catchment)
  • Brush wood in a small Scottish burn would score 3 (frequent use of technique but not in that catchment)
  • The output is essentially a measure of how unpredictable the response to the restoration works will be.
Table 6.1: Risk Calculation Matrix 1 = Frequency of successful application.
Frequency of successful technique application in you catchment or area
Frequency of use anywhere Frequently Often Rarely
Frequently 1 2 3
Often 2 3 4
Rarely 3 4 5


‘Robustness’ and potential for physical failure

Examples of river types

Table 6.2 then considers potential „structural‟ failure of the technique(s) in relation to your river typology – in particular, how much energy is in the system. Work completed by Thorne and Sear 2009 (see Appendix 7) has identified a working river typology for river systems in the UK and can be used as a good basis to help define your river type. The key elements of this are shown in the bullets below, with more details in the Appendix. Each type is related to the broad upland, intermediate and lowland categories in Table 6.2.

Definition of key river types

  • Steep headwater channels = Upland River
  • Pool-Riffle and Plane bed channels = Intermediate River
  • Wandering gravel-bed rivers = Intermediate - Lowland River
  • Braided rivers = Upland River
  • Active Meandering alluvial channels = Intermediate/ Lowland River
  • Passive Meandering = Lowland River
  • Groundwater dominated rivers = Intermediate/Lowland River
  • Channelised watercourses (&omega>30 Wm-2) = Intermediate/High River
  • Channelised watercourses (&omega< 10 Wm-2) = Lowland River
  • Tide Locked Watercourses = Lowland River

Applying the example of brush wood structures in a chalk stream, though the technique may not be the most physically robust or resilient (say, medium), in such a lowland, groundwater dominated river, this does not significantly affect the risk.

Thus: The risk of physical failure is rather low for a lowland river = 2 Conversely, considering using the same technique in a constrained high energy, mobile gravel bed river would significantly increase the risk of failure, coming out as 4.

Table 6.2: Risk Calculation Matrix 2 = Failure risk for river type.
River Type
'Robustness' of technique Lowland Intermediate Upland
High 1 2 3
Medium 2 3 4
Low 3 4 5


Combining previous application and failure potential

The two elements of risk are then brought together to give an overall risk factor which ranges from A to C as shown in Figure 6.1. This then gives you the position in the vertical part of the matrix in Figure 6.1.

Table 6.3: Overall risk score
Frequency of use matrix result
Risk of failure for river type matrix result 1 2 3 4 5
1 A A A B B
2 A A B B B
3 A A B B C
4 A B B C C
5 B B C C C


6.3.2 Identifying project scale

Project scale is best considered as a function of the length and the width of a river as shown in Table 6.4

Table 6.4: Scale Factors Relating to Length and Width of Restoration Reach
Project Length (m)
Channel Width (m) <50 50-100 100-200 200-500 >500
<2 A A B B C
2-10 A A B C C
>10 B B B C C

6.3.3 Assigning resources and level of monitoring

Figure 6.1: Project Size and risk to help identify appropriate monitoring level and hence method(s).

Whilst determining the size of your river is relatively easy, the level of risk (of technique failure) is less straight forward to assess.

Project risk can be increased by one of the following:

  • Installation of a new technique
  • Integrating established techniques in a different way (i.e. mix of techniques together)
  • Using an established technique in a different environment
  • Situations where several interconnected sites are involved that are being considered together especially where impacts may be cumulative.

In summary where your project sits in the generic matrix shown in Figure 6.1 is derived from a combination of Table 6.3 and 6.4. Using this process can help to assist in determining the validity of your idea AND the level of monitoring that should ideally be undertaken for your project. Figure 6.3 and the accompanying examples below it, demonstrate this process.

Figure 6.3: Risk and Scale matrix to help determine the appropriate level of monitoring
7: Innovative projects with risk of failure. Monitor using detailed hydromorphological studies by experts (e.g. fluvial audit) coupled with best-practice ecological methods. 8 9: Complex and innovative projects requiring large scale scientific studies by a research institution. C: High Risk of failure
4: Established techniques in new environments, or relatively untested techniques. Monitor using simple habitat and species methods. 5 6: Same as box 4 but on a larger scale. Use habitat and species monitoring methods that can be applied over larger distances. B: Med
1: Established techniques over a small scale. Monitor using methods such as fixed-point photography. 2 3: Established techniques over a lagre scale. Monitor using methods such as fixed-point photography and citizen science. A: Low
A: Small B: Medium C: Large
Scale


6.3.4 Examples of using the matrices

Installation of Upstream Facing Deflectors in a 50m Reach of Chalk Stream in semi-urban setting

Installation of upstream facing deflector
  • Upstream facing deflectors are a frequently used method in a chalk stream. Using Table 6.1 = 1
Frequency of successful technique application in you catchment or area
Frequency of use anywhere Frequently Often Rarely
Frequently 1 2 3
Often 2 3 4
Rarely 3 4 5
  • The risk of structural failure is low in a low energy predominantly ground water fed stream. Using Table 6.2 = 1
River Type
'Robustness' of technique Lowland Intermediate Upland
High 1 2 3
Medium 2 3 4
Low 3 4 5
  • Linking scores from both tables to assess the overall risk using Table 6.3. Overall risk = ‘A’
Frequency of use matrix result
Risk of failure for river type matrix result 1 2 3 4 5
1 A A A B B
2 A A B B B
3 A A B B C
4 A B B C C
5 B B C C C
  • Project scale is 60m in length and the stream falls in the 2-10m wide category. Using Table 6.4 = ‘a’
Project Length (m)
Channel Width (m) <50 50-100 100-200 200-500 >500
<2 A A B B C
2-10 A A B C C
>10 B B B C C
  • Project location in matrix as shown in Figure 6.3 = BOX 1
7 8 9 C: High Risk of failure
4 5 6 B: Med
1 2 3 A: Low
A: Small B: Medium C: Large
Scale


Creation of New Channel Meander for 300m of a Clay Catchment with Significant Urban Runoff

Creation of a new channel meander
  • Creating meanders is tried and tested method but in this area, we haven't applied it very often in urban settings. Using Table 6.1 = 3
Frequency of successful technique application in your catchment or area
Frequency of use anywhere Frequently Often Rarely
Frequently 1 2 3
Often 2 3 4
Rarely 3 4 5
  • In a lowland river the risk of failure will be low, however given the urban influences and the degree of modification the risk is slightly increased. Using Table 6.2 = 2
River Type
'Robustness' of technique Lowland Intermediate Upland
High 1 2 3
Medium 2 3 4
Low 3 4 5
  • Linking scores from both tables to assess the overall risk using Table 6.3. Overall risk = ‘B’
Frequency of use matrix result
Risk of failure for river type matrix result 1 2 3 4 5
1 A A A B B
2 A A B B B
3 A A B B C
4 A B B C C
5 B B C C C
  • Project scale is 600m in length and the stream falls in the 2-10m wide category. Using Table 6.4 = ‘C’
Project Length (m)
Channel Width (m) <50 50-100 100-200 200-500 >500
<2 A A B B C
2-10 A A B C C
>10 B B B C C
  • Project location in matrix as shown in Figure 6.3 = BOX 1
7 8 9 C: High Risk of failure
4 5 6 B: Med
1 2 3 A: Low
A: Small B: Medium C: Large
Scale


Multiple Engineered Log Jams in a high energy river

Log jam in a river
  • Engineered log jams have been used especially in the USA. However, the use in the UK is limited so the evidence of success in high energy rivers in the UK is limited so risk will increase. Using Table 6.1 = 4
Frequency of successful technique application in your catchment or area
Frequency of use anywhere Frequently Often Rarely
Frequently 1 2 3
Often 2 3 4
Rarely 3 4 5
  • Use of this technique in a high energy river using Table 6.2 would give the

risk as 4 (medium risk of failure in a high energy river).

River Type
'Robustness' of technique Lowland Intermediate Upland
High 1 2 3
Medium 2 3 4
Low 3 4 5

The two scores combined would give an overall risk of C from Table 6.3.

Frequency of use matrix result
Risk of failure for river type matrix result 1 2 3 4 5
1 A A A B B
2 A A B B B
3 A A B B C
4 A B B C C
5 B B C C C
  • Project scale is 250m in length and the stream falls in the >10m wide category. Using Table 6.4 = ‘C’
Project Length (m)
Channel Width (m) <50 50-100 100-200 200-500 >500
<2 A A B B C
2-10 A A B C C
>10 B B B C C
  • Project location in matrix as shown in Figure 6.3 = BOX 1
7 8 9 C: High Risk of failure
4 5 6 B: Med
1 2 3 A: Low
A: Small B: Medium C: Large
Scale


6.4 Setting SMART monitoring objectives

Having defined your project and considered the development and implementation associated risk, SMART monitoring objectives can then be set.

6.4.1 Is your monitoring achievable and realistic?

What is achievable and realistic in terms of monitoring will depend on a combination of:

  • Current knowledge associated with your project (i.e. current knowledge of the river restoration technique that is to be applied) which relates to project risk as depicted in Figure 6.3.
  • Resources – budget for data collection and analysis; number of people to collect information or will you need to rely on a 3rd part to collect some/all information?
  • Timescale – how long can you monitor after project completion?
  • Pre-project data – what is available, in what format, when was the data collected and over what period of time?

Applying these generic questions to each specific monitoring objective will lead to a clear recommendation of what is actually achievable.

6.4.2 Prioritising your monitoring

The techniques and the level of assessment that can be applied to each objective will depend on the importance associated with that objective, and your resources. Ideally, all aspects of a project‟s objectives would be monitored in detail. In reality this is unlikely to be feasible and some level of prioritisation will be necessary for specific aspects as shown in Table 6.5.

Table 6.5: An example of prioritising your monitoring
Priority Parameter Purpose Outcome
1 Siltation Ensure that downstream spawning gravels are not adversely affected by the weir removal Any fine sediment stored behind the weir will be flushed through the system resulting in no overall change in silt loading of existing spawning gravels.
2 Fish passage Demonstrate success of project for fish passage during migration period Significant increase in migration upstream of brown trout
2 Catching Spawning (downstream gravels) Detect change in spawning rates No deterioration in numbers of redds as a result of weir removal
3 Spawning (upstream gravels) Detect change in spawning rates Increase in numbers of redds and subsequent fry over period of surveys
4 Channel width Ensure that the technical specification of the river restoration techniques applied to narrow the channel have been successful Initial intervention to narrow channel works with natural processes to create a new channel feature appropriate to channel type. Identify any future adaptive management that may be necessary to ensure continuous success of project

In this example, siltation of existing spawning beds has been deemed the most important aspect to assess and has hence been prioritised highly, and will be the main focus of monitoring resources. To support this, though, numbers of redds could be counted by a simple walk over survey – i.e. with limited resource input. Fixed point photography could also provide an idea of the approximate percentage of channel narrowing occurring and identify any future management needs. A decision may be made that electro fishing once a year is the most effective way of measuring fish passage. Appropriate techniques for your project are discussed in more detail in Section 7.

6.5 Mayes Brook case study

Mayes Brook is a case study in Section 11 of this report. The project is at the planning stage and determining monitoring is an integral part of the project. Table 6.2' is a snap shot of the process used so far to prioritise monitoring needs and is proofing to provide a good method.

Table 6.6: A snapshot of the Mayes Brook way of prioritising river restoration monitoring aspirations based on how the objectives fit with the project aims and costs of each element. Priority is based on a combination of need and relation to objectives, data availability, cost and other resources.
Target / Objective:
Why?
Measurable:
What?
When? Method:
How?
Who is available to complete monitoring? Existing Data? Estimated Cost? Priority
Target: Improved river geomorphology as a result of the project

Why: To assess changes to in-stream cross sectional diversity
Change in the river planform Pre works; as built, just post works and repeat every 2 years Fixed point photography mapped with GPS co-ordinates for future use.

Note: can link with Urban river corridor survey, river habitat survey and a river corridor survey. RHS / RCS / Biotope data to indicate where to carry out cross sections
Initial consultant with river restoration expertise. Then follow up by local groups with training. Some limited fixed-point photography £2000 for initial work 1
Target: Increased fish populations in brook by 2013

Why: To see if the density of fish and the retention of fish has increased and project is resilient to climate change.
Number and types of fish species April 2012 then every two years Electrofishing- point abundance survey method EA will collect this data and will be responsible for it Baseline, one off point abundance survey done April 2008 In-house (EA) (3 days work). Externally it would be about £3k 3