DD2496 Climate Change Adaptation Delivery

1.1. London is outgrowing its drains and sewers.  The combined sewer system originally built over 150 years ago by Joseph Bazalgette has served us well, but it was designed for a smaller city with more green surfaces.  Rapid urbanisation and development across the capital has resulted in an increase in impermeable surfaces. In addition to this climate change means that London is likely to continue to experience wetter, warmer winters, and heavier summer showers, highlighted by the fact that in December 2018 the Mayor declared a climate emergency.

1.2. The combined challenges of London’s growing population, changing land uses and changing climate mean that if we continue to rely on our current drains and sewers, we face an increasing risk of flooding. This flooding can damage property, affect transport, impact the economy, pose a danger to health and wellbeing, and pollute the environment.

1.3. To make the most effective use of our existing and planned drainage infrastructure and avoid increased flood risk, we need to change how London’s drainage system operates. Rainwater should be managed as a valuable resource rather than a waste product.  We need to roll back the tide of impermeable surfaces. They should be replaced with ‘sustainable drainage’ systems (SuDS). SuDS manage surface water runoff (the flow of rainwater across the surface) by capturing, using, absorbing, storing and transporting rainfall in a way that mimics nature. SuDS slow the flow and reduce the amount of rainfall that drains into sewers, streams and rivers which reduces the risk of flooding. They can also treat and reduce pollutants in runoff. The most beneficial SuDS manage rain close to where it falls, are on (or close to) the surface and often include vegetation.

1.4. SuDS are widely accepted as a better approach to managing rainfall than traditional drainage and are embedded in our national and local planning systems including in the Mayor’s London Plan. They create beautiful spaces and places for people and wildlife, as well as reduce the risk of waterlogging, local flooding and water pollution. SuDS will be fundamental in responding to the climate and ecological emergencies we’re facing as they are one of the few measures that provide a tangible approach to help London adapt to changes in climate as well as delivering improved resilience and biodiversity gain. The importance of retrofitting SuDS was highlighted within the London Assembly Environment Committee’s “The Climate Emergency: Extreme Weather and Emissions” (April 2020) report.

1.5. In 2010 the GLA established the Drain London programme in response to the need to better understand and manage surface water flood risk in London (MD455). The project was awarded a £3,200,000 grant from Department for Environment, Food and Rural Affairs (DEFRA). The first stages of the programme delivered surface water flood risk mapping and management plans for all 32 London boroughs and the City of London. The programme also delivered detailed studies into 28 areas of high surface water flood risk and a range of pilot demonstration projects showing how sustainable drainage measures can be retrofitted into the urban environment.

1.6. The Drain London programme demonstrated that the retrofitting of small-scale SuDS features across whole catchment areas was the only practical opportunity to reduce flood risk in urban areas due to the common constraint on space within the public realm to construct larger or strategic flood risk management schemes (e.g. flood storage areas).

1.7. In December 2016 the London Sustainable Drainage Action Plan (LSDAP) was produced. This plan promotes the retrofitting of SuDS to existing buildings, land and infrastructure and includes 40 actions identified at encouraging this across a wide variety of sectors, most of which have either now been delivered or are well underway. This proposal aims to build upon some of those actions identified within the LSDAP in order to help develop the evidence necessary to enable local authorities unlock further external funding towards the delivery of retrofit SuDS across London.

1.8. The projects within the proposal directly contribute toward the delivery of a number of London Environment Strategy Objectives (5.1, 5.3 and 8.2). The London Environment Strategy also includes a commitment to switch 200 hectares of land from draining directly to conventional sewers or London’s watercourses to draining to SuDS by 2030, something this programme will help contribute towards meeting.

1.9. The projects will also contribute towards the Green New Deal as we look to double London’s green economy by 2030. Sustainable Urban Drainage systems are identified under the transport and public realm pillar of the mission. The measures identified here will contribute towards unlocking funding and increasing of skills which will help contribute towards increasing SuDS retrofitting towards the needed levels which could eventually see an estimated 700 jobs sustained and £280m of flooding and natural benefits delivered per year.

1.10. The projects identified below are further complemented by the physical works delivered through the Build Back Greener grants programme (MD 2665), with £125,000 of grants monies specifically allocated towards climate change adaptation measures, primarily SuDS.

1.11. Note that in addition to this DD is an ADD which is seeking approval at the same time to continue the work of the Drain London Programme in addressing surface water flood risk utilising remaining budget originating from external funding (DEFRA). Previous decisions related to the Drain London programme include MD2339, MD455, DD899, DD1250, DD1322 and DD2064.

2.1. The projects identified below have been developed following discussions with key stakeholders (including local authorities, TfL, Environment Agency, Thames Water and environmental NGOs) on how the GLA can best encourage greater SuDS (both from a quality and quantity perspective).

3.1. Under Section 149 of the Equality Act 2010, as a public authority, the Mayor of London must have ‘due regard’ of the need to eliminate unlawful discrimination, harassment and victimisation as well as to advance equality of opportunity and foster good relations between people who have a protected characteristic and those who do not.

3.2. The projects included within this DD form part of the policies and proposals in the London Environment Strategy which has been informed by a full Integrated Impact Assessment, including consideration of equalities.

3.3. The projects listed in this DD look to maximise their positive impact on all Londoners including for example: reducing the risk of flooding, increasing access to green space, contributing to urban cooling, and reducing the health impact of air quality.

3.4. Projects within this DD that have location specific outputs (modelling) will aim to prioritise areas of London considered to be most vulnerable to the impacts of climate change, work being delivered in conjunction with Bloomberg Associates at present. This innovative mapping takes into consideration a number of different exposure and vulnerability metrics and will help to ensure that work is delivered for the areas of London with the greatest need.

4.1. The key risks and issues are set out in the table below.

Links to Mayoral strategies and priorities

4.2. The projects included within this DD will contribute towards:

• meeting the London Environment Strategy proposal around implementing the actions of the London Sustainable Drainage Action Plan (Proposal 8.2.3b);

• meeting the London Environment Strategy proposal around providing a stronger evidence base for green infrastructure programmes (Proposal 5.3.1c);

• meeting the Mayor’s Transport Strategy proposal around annual SuDS delivery (Proposal 44);

• meeting the London Health Inequalities Strategy objective for a greener city where all Londoner have access to good quality green spaces (Objective 3.3); and

• meeting the London Recovery Board high-level outcome to deliver a cleaner, greener London.

Conflicts of interest

4.3. GLA officers are not aware that anyone involved in the drafting or clearance of this DD has any conflicts of interest with the proposed projects.

4.4. If any conflicts of interest arise during the procurement process, they will be required to declare that interest and not take any part in procurement process for that particular project.

5.1. Approval is being sought for the expenditure of up £125,000 on sustainable drainage projects which improves London’s sewage and drainage systems.

5.2. The breakdown of this expenditure is shown above in section 2 of this report.

5.3. All expenditure will be accounted for within the current financial year and funded from the 2020-21 Climate Change Adaptation Delivery budget held within the Environment Unit.

6.1. The foregoing sections of this report indicate that:

(a) the decisions requested of the Director concern the exercise of the GLA’s general powers, falling within the GLA’s statutory powers to do such things considered to further or which are facilitative of, conducive or incidental to the promotion of economic development and wealth creation, social development or the promotion of the improvement of the environment in Greater London; and

(b) in formulating the proposals in respect of which a decision is sought officers have complied with the Authority’s related statutory duties to:

- pay due regard to the principle that there should be equality of opportunity for all people;

- consider how the proposals will promote the improvement of health of persons, health inequalities between persons and to contribute towards the achievement of sustainable development in the United Kingdom; and

- consult with appropriate bodies.

6.2. In taking the decisions requested, the Director must have due regard to the Public Sector Equality Duty; namely the need to eliminate discrimination, harassment, victimisation and any other conduct prohibited by the Equality Act 2010, and to advance equality of opportunity and foster good relations between persons who share a relevant protected characteristic (race, disability, sex, age, sexual orientation, religion or belief, pregnancy and maternity and gender reassignment) and persons who do not share it (section 149 of the Equality Act 2010). To this end, the Director should have particular regard to section 3 of this report.

6.3. Officers have indicated in section 2 of this report that they intend to procure the services required for the projects via an appropriate framework, or, if no framework exists, a minimum of three parties will be invited to tender in accordance with the GLA’s Contracts and Funding Code. Officers must ensure that:

(a) the framework under which it is proposed the services required are to be “called-off” was procured in accordance with the GLA’s Contracts and Funding Code or can be used by the GLA by virtue of its procurement by an appropriate central purchasing body on behalf of the GLA in accordance with relevant procurement law;

(b) the services required will be procured fully in accordance with the requirements of that framework; and

(c) appropriate “call-off” documentation (or contract documentation if inviting three tenders) is put in place and executed by the successful bidder(s) and the GLA before the commencement of the services.

6.4. With regards to seeking technical input directly from the authors of the guidance on SuDS, Section 3 of the Contracts and Funding Code (the ‘Code’) requires the GLA to seek three or more written quotations in respect of the services required or call off the services required from an accessible framework or conduct an advertised tender for the services required. However, the director may approve an exemption from this requirement under section 5 of the Code upon certain specified grounds. One of those grounds is that the approval of the exemption is justified because it affords compatibility with an existing service. Officers have indicated in section 2 of this report that they intend to seek the authors’ technical input directly because this is compatible with the authors having written the original reports which will be relied on to produce the training materials. On this basis the director may approve the proposed exemption if satisfied with the content of this report.

7.1. The projects identified within this DD will require the procurement of external expertise to help in the delivery. An estimated timetable for each project is shown below.

Modelling:

Training:

Guidance:

Research: