I submitted a Freedom of Information request on 9 March asking what analysis and planning had been undertaken over the years in relation to estate-wide drainage across the Barbican podium.
I received the response today. In short, the answer is: very little.
The City confirms that there is no estate-wide drainage strategy, no system-wide modelling, and no meaningful record of drainage maintenance.
The response is, in my view, quite revealing.
Below is a short summary of the key points arising.
---
Summary
The proposed Phase 2 podium works are being presented as a solution to long-standing drainage issues on the Barbican highwalks. However, information disclosed by the City of London under the Freedom of Information Act, together with earlier project documentation, raises serious questions about whether the underlying drainage problems are being addressed in a systematic and effective way.
Key Findings
1. No estate-wide drainage strategy or modelling
The City has confirmed that:
- no estate-wide hydraulic modelling of the podium drainage system has been undertaken
- no comprehensive estate-wide drainage strategy exists
Drainage is therefore not being managed as a coherent system, despite persistent issues across the estate.
2. No maintenance records for drainage infrastructure
The City has stated that:
- no records are held for drainage maintenance, blockages, or clearance over the past five years
This makes it difficult to assess:
- whether drainage problems are due to design or maintenance
- whether proposed works will lead to measurable improvement
3. Phase 1 explicitly excluded drainage
A post-project technical review of earlier works states:
“This was a waterproofing project only… it would have been desirable to include podium drainage as well.”
Despite this acknowledged limitation, similar issues (ponding, blocked drains, surface deterioration) are already visible in the refurbished western highwalk.
4. Investigations are local, not system-wide
Recent technical work has focused on:
- local leak investigations (e.g. Beech Gardens)
- thermographic and radar surveys
- structural movement monitoring
These are targeted diagnostics, not a comprehensive assessment of the drainage network across the estate.
5. Works are being delivered on a phased, project-by-project basis
The City confirms that podium works have been developed:
- on a phased basis
- informed by local condition and individual project approvals
There is no evidence of a coordinated, estate-wide approach to drainage infrastructure.
Implications
- The root cause of drainage issues appears to be systemic rather than localised
- Addressing drainage only within the Phase 2 footprint risks repeating the shortcomings of Phase 1
- Without modelling, strategy, or maintenance data, it is unclear how improved drainage performance can be assured
Key Question
What estate-wide analysis has been undertaken to demonstrate that Phase 2 will resolve drainage issues at a system level, rather than simply within the project boundary?
Conclusion
There is a clear risk that Phase 2 prioritises surface renewal and capital works over addressing the underlying drainage system across the Barbican Estate. A more effective approach would be:
- an estate-wide drainage assessment
- a coordinated maintenance and repair programme
- targeted surface works where required
Until such a strategy is in place, confidence in the long-term effectiveness of the proposed works is necessarily limited.
