This document discusses challenges and opportunities for restoring the Camac River in Dublin City while managing flood risk, supporting urban renewal, and adapting to climate change. The river suffers from channelization, loss of floodplains and wetlands, and lengthy culverts. Restoration requires tackling existing issues and avoiding new pressures. Opportunities include maximizing green space, rezoning industrial lands, and creating a greenway. Successful restoration requires considering the whole catchment and securing sufficient land, and balancing priorities like flood protection, development, and environmental goals. Planning tools like new zoning objectives can help protect land for restoration and climate adaptation.

1. River Restoration in Dublin
City
Challenges and Opportunities on the Camac River in the face of flood
risk management, urban renewal and climate change
Mary-Liz Walshe BA, BAI, MSc, MIEI
Project Manager of the Regional Camac Flood Alleviation Scheme (Civil Engineer/Spatial Planner)
Dublin City Council Water Framework Directive Office

2. Introduction to Camac River
• Different land uses &
Different pressures
• 400 buildings at risk
from fluvial flooding
• Two Local Authorities
• Current Status
• Key pressures and
solutions
• NWRM
• Natural river =
Healthy river =
Robust river

3. • Lengthy culverts
• Channelisation
• Loss of floodplains,
wetlands, riparian
corridors
• Flood storage and
habitats
• River processes
• Base flow?
Camac River Lower Catchment:
Hydromorphology

4. Camac River Mid and Upper Catchments:
Hydromorphology
• Channel over deepened
• Brittas Ponds

5. Camac River:
Hydromorphology
• Tackling existing hymo
pressures
• AND
• Avoiding unnecessary
new ones

6. Camac River: Hydromorphology
• Challenges and opportunities
• Camac Flood Alleviation Study
• Maximising existing green space
• Rezoning of industrial lands and
development control
• Camac Greenway
• River Restoration Plan
• synergies
Photo courtesy of the RRC

7. Camac River Rehabilitation and Flood Alleviation Scheme
2019: Considerations
• At risk of not achieving ‘good status’ by 2027 in part due to
hydromorphological condition.
• Sufficient existing green space to provide floodplain storage and other
Hymo NWRM?
• Impact of constructing new flood walls and increasing the heights of
existing walls?
• Lengthy culverts in private lands.

8. Fishing, Swimming, Canoeing, Nature
study, Maintenance
Picnic areas, fishing stands, Bird hides
Trails, grasslands, picnic areas, Grass
Pitches, mostly low-maintenance
Retention and detention strategies
Buildings, Roads, Cycle-ways, structures
Retention and detention structures,
drainage systems
DWF
Normal/ Baseflow
Bankfull Max Channel Flow 10 year flood
100 yr Flood
ZONE 1 ZONE 2 ZONE 3 ZONE 4
RIVER
2- 6m [from c line]
RIVERBANK
6 – 12 m[from c line]
FLOODPLAIN
[12 – 100m from c line]
RIVER VALLEY
[floodplain to watershed]
WILD NATURAL MANAGED OCCUPIED
No Use, Water Access
Only
Occasional Access Limited Access Universal Access, All uses
Emergent Vegetation
Herbaceous Vegetation
Free Flow
C
L
Erosion Deposition
1m
Extracted from Draft Conceptual Framework for Urban River
Rehabilitation by Conor Skehan, DIT , 2018.
Planning
for…..

9. Need to Plan the
Whole Catchment
• Instream measures insufficient for
WFD Status improvements
• Must work to restore all river
processes and plan the whole
catchment
• Need land
• Collaboration with OPW, other
council departments, local
community
• Forward planning, RSES

10. Camac Catchment Analysis
Investigating interactions between River Restoration, Climate Change
Adaptation, Urban Renewal and Landuse Planning, and Flood Risk
Management

11. Urban Renewal, Flood Risk Management and Climate
Change, River Restoration, Nature/Biodiversity...
Everybody needs land! So what now?
Understanding the river’s condition
• Protect what is vulnerable/valuable…
• Defining the problems/opportunities Setting priorities
Is sufficient suitable land available now? Does the river need more?
• Land for natural floodplains, for riparian habitat restoration, (for SuDS retrofit)... Establishing land requirements
How can we secure additional land for rivers? Dedicated funding? CPO? Zoning?
Different mechanisms Different timescales for delivery
Solution delivered in phases? Identifying synergies
Achieving a balance: ‘Not here’ or ‘not yet’ Different priorities for
different sections?

12. Higher walls for a growing tourism quarter?
Or additional floodplain Storage?
Availability of land? Development Pressures
Social acceptance/Economy/Amenity

13. • Greater flows inside M50
• Need additional storage here
• Long culverts
• Space for natural floodplains, etc?
• New thinking on use of public parks?
• Prevent new hymo pressures: Guidelines for
planning (OPW flood maps)
• Opportunities for enhancements?
• New Hydromorphology Assessment
Methodology (RRC for DCC)
• Define and understand the problems

14. • Future pressures but potential opportunities
for NWRM retrofit (LAP’s, URDF’s, rezoning...)
• Preserve existing floodplains/riparian zones
and reinstate historical ones
• Also opportunity to tackle other WFD
pressures e.g. buffer zones along roads?

15. Photo RRC

16. River Restoration and
Greenway Planning for River
Camac

17. Planning a river-friendly greenway
Planning A Greenway: Splitting
Habitats
Planning A Greenway: Habitat
‘Stepping Stones’
Extracted from Draft Conceptual Framework for Urban River Rehabilitation by Conor Skehan, DIT , 2019.

18. Working Towards a Camac
River Restoration Plan

19. Protection for Future River Restoration
through Land Zoning
Protecting floodplains and riparian corridors for
significantly modified rivers is challenging
SuDS retrofit to address particular pressures
Need a solid basis for zoning decisions
Finding the evidence
Hydromorphological Assessment Methodology
Biological Condition
Surface Water Quality

20. Wider WFD Considerations and Planning
Decisions
1. Morphology
• Flooding – flow and storage
• Erosion and deposition
2. Water Quality
• Assimilative Capacity for discharges
• Assimilative capacity for runoff
3. Biodiversity
• Habitats & Resources
• Flow levels
4. Beneficial Uses
• Recreation & Amenities (White water rafting?)
• Access & Routes (Greenway?)
1. Identify Issues
2. Assess Capacity
3. Agree Priorities
4. Assign Roles
5. Arrange Implementation
Extracted from Draft Conceptual Framework for Urban River Rehabilitation by Conor Skehan, DIT , 2019.

21. Synopsis
• Balance between WFD, Floods Directive... achieving synergies first…
• housing, transport, tourism and… healthy living/working environments… climate adaptation
• Making room for the river
• New zoning objectives for ‘River Protection and Climate Adaptation’? Etc.
• Hard-working, multipurpose green space
• Change in mind-set! Not wasted land!
• When we strip out nature, we make ourselves vulnerable
• Importance of forward planning and integrated catchment management planning

22. Thank you
• Email: maryliz.walshe@dublincity.ie