Appendix 3

Page 1

Appendix 3 – Invergowrie NFM Study – Short List of Potential Options 
Table 1: Option Appraisal Summary Table 
Option 1 
In channel measures to
attenuate flows along the
upper Fowlis Burn including
riparian planting, leaky
dams, and woodland
management in Fowlis Den 
Option 2 
Catchment wide measures
including reforestation,
distributed surface water
storage, and sustainable land
management practices 
Option 3 
Structural measures including
de-culverting sections of the
Fowlis Burn, incorporating a
bypass channel close to Fowlis,
and removing embankments to
reconnect the Fowlis Burn with
its floodplain 
Option 4 
Direct Flood Defences within
Invergowrie including walls
upstream and downstream of
Main Street and Burnside Road 
Option 5 
Non-structural measures such as
more frequent and extensive
inspection visits of structures in the
upper catchment; the promotion of
sustainable land management (such
as enhanced flood water storage or
woodland planting), property buy-
back, awareness raising, and
updates to local planning policies to
consider flood plain management 
Properties protected  
in 1 in 200 year flood  0 12 12 16 0*
Initial Capital 
Cost £425,600 £2,032,240 £2,340,800 £2,128,000 £4,583,240
Benefit/Cost Ratio 0.00 0.21 0.30 0.08 0.20
Assessment of Option
Option doesn’t fully meet
study objectives. 
Potential for the installation of
leaky dams and riparian
planting. 
Small ecological benefit noted,
but unlikely to improve
watercourse condition. 
Very limited benefit in terms
of reducing flood risk.
Option doesn’t fully meet study
objectives. 
Modelling indicates that
catchment wide measures
would have a limited benefit in
terms of reducing flood risk. 
Significant flood storage volume
required to reduce flows
reaching Invergowrie; this would
be extremely large and
benefit/cost would be low. 
Further issues noted with land
ownership and maintenance.
Option doesn’t fully meet study
objectives. 
Measures are costly and would
require extensive work on the
watercourses. 
Option has a limited benefit in
terms of reducing flood risk.
Option doesn’t fully meet study
objectives. 
Measures could potentially lead to
a deterioration in the
environmental status of the
watercourse. 
Works would be intrusive and
require substantial construction
and land resources. 
Option has a limited benefit in
terms of reducing flood risk. 
Option doesn’t fully meet study
objectives. 
Option includes a mix of measures; the
main benefit would be derived from
buying (*not protecting) 28 properties
& re-naturalising flood plains over the
longer term. Landownership would be
a major constraint. 
Benefits would be realised over long
term; requiring long term investment. 
Would provide wider benefits from
education and engagement. 
Option 1 is not
recommended
Option 2 is not
recommended
Option 3 is not 
recommended
Option 4 is not 
recommended
Option 5 is not 
recommended