Greater Cambridge Local Plan: Proposed Submission

We support the inclusion of Policy BG/BG, but we recommend that either the policy or supporting paragraphs also include a clear requirement for biosecurity measures to prevent the spread of invasive species. Development proposals must demonstrate implementation of recognised protocols such as ‘Check, Clean, Dry’ to minimise the risk of transferring invasive non-native species. This aligns with national biosecurity best practice and the increasing need to protect waterways and safeguard native biodiversity.

We believe this policy to be sound as it pertains to water quality.

Waste Management

We welcome the reference to CL:AIRE Definition of Waste Development Industry Code of Practice (DoWCoP) in Policy CC/CE: Supporting a circular economy and sustainable resource use, Operational waste management point 8.

In parts 1i & 1j we recommend changing ‘plus an allowance for climate change’ to ‘including an appropriate allowance for climate change.’

In part 1j the allowance should be changed to 600mm above the 1 in 100-year flood level (including an allowance for climate change), as this is our current requirement.

We welcome the inclusion of a requirement for safe access in 1.d. You may wish to further define what is considered as safe access, either in the policy itself or the supporting text. For example, is a dry route of escape required or is some depth of flood water along the route acceptable? This point should also clarify when emergency plans need to be provided.

In parts 1i & 1j we recommend changing ‘plus an allowance for climate change’ to ‘including an appropriate allowance for climate change.’

In part 1j the allowance should be changed to 600mm above the 1 in 100-year flood level (including an allowance for climate change), as this is our current requirement.

Recommended Additions to Policy CC/FM

Natural Flood Management (NFM) – we recommend that reference is made to the need for development proposals in flood risk areas to demonstrate that all reasonable opportunities to use natural flood management techniques or nature-based solutions to reduce flood risk overall have been considered and taken, in line with policy F2: 1.C. of the NPPF. We recommend that this is added to the policy or that it is referenced in para 4.39. This is supported by the requirements of policy CC/IW.

Sustainable Drainage Systems (SuDS)

We are pleased to acknowledge Policy CC/IW: Integrated water management, sustainable drainage and water quality. We support the inclusion of this Policy and the need for appropriate water treatment and pollution control measures.

Related to 1(b), SuDS should be considered at an early stage as it may be necessary to collect data on seasonal groundwater levels to inform the assessment and design. It would be prudent to detail this in supporting information to ensure the policy is effective.
Deep infiltration systems are not considered to be routinely acceptable. A permit from the Environment Agency may be required for such systems.

We support reference to relevant literature including CIRIA SuDS Manual and National Standards for SuDS in the policy, as well as Environment Agency’s groundwater protection guidance in the supporting information.

Water Quality

We note the inclusion in section 6.a of the following – “…..adequate wastewater conveyancing infrastructure to serve the whole development…” This statement appears to imply that there must be enough infrastructure, not that there must be sufficient capacity within that part of the system. However, the text in the supporting information (4.36) clarifies that capacity must be considered. We welcome the inclusion of phasing conditions where necessary, which will be important to protect water quality. If the supporting information to the policy is taken as part of the policy, then we believe it to be sound.

The area covered by this Local Plan is defined as being in an area of serious water stress. We support the water efficiency requirements highlighted in the Local Plan and supporting evidence base and consideration to phasing certain development linked to Cambridge Water Company's strategic supply options delivery.

The evidence indicates that the sustainability and delivery of planned growth is heavily dependent on Cambridge Water Company's Water Resources Management Plan 2024 (WRMP24) being implemented successfully and the planned demand management and supply measures performing as forecast.

Whilst the Local Plan has been informed by the latest WRMP24, there remains some uncertainty regarding future water availability and the timing of strategic supply schemes. If WRMP24 measures are delayed or prove less effective than expected, there is an increased risk of pressure on water resources before new sustainable water supplies become available, including the planned Grafham transfer and Fens Reservoir.

We recognise that water companies need to plan for future demand and that Local Planning Authorities (LPA) are generally expected to rely upon the approved WRMP process. However, given the degree of reliance placed on WRMP24 delivery, it will be important that progress is monitored closely and that any material deviation from planned outcomes is considered alongside the assumptions that underpin the Local Plan's growth strategy.

The evidence base submitted in support of the Local Plan correctly recognises the importance of monitoring WRMP24 delivery and notes that Cambridge Water will provide annual WRMP24 reporting. The Local Plan also contains a wider monitoring framework and annual monitoring commitments. We note that the Local Plan monitoring framework and Infrastructure Delivery Plan (IDP) include mechanisms to monitor the delivery of infrastructure projects, including strategic water supply schemes. The IDP identifies the Grafham Water transfer and Fens Reservoir as critical water supply projects supporting growth. Continued monitoring of WRMP24 delivery, including progress against key strategic supply schemes and demand management measures, will therefore be important to ensure that the assumptions underpinning the Local Plan remain valid. The monitoring framework should also consider if any updates are required to the Plan as a result of WRMP29 when published. The Infrastructure Delivery Plan's review mechanisms provide an important route for considering any implications arising from any potential delays or changes to planned water resource delivery. We encourage GSCP to consult with us if any changes are required through the IDP and monitoring framework.

Since our representation on the Regulation 18 stage of the Plan, we have engaged with yourselves and your consultants on the WCS evidence base. We previously, recommended that more detailed assessment be included in an updated detailed WCS. We note section 2.3 of the WCS Wastewater Addendum (2026), in which Stantec have summarised our Position. We would generally agree with this summary, however, we wish to clarify some key points, as follows.

Whilst there was concern about the potential for duplication of the work set to be undertaken by AWS as part of the DWMP process, we would still consider LPAs have the capability to commission their own studies to ensure their own evidence base underpinning the Plan and Policy wording is robust. In this instance, having engaged with GCSP on a Statement of Common Ground, we acknowledged that the complexities and time available to the LPA and their consultants as engagement progressed presented limitations, therefore we took a balanced viewpoint and recommended capturing the outstanding gaps in more detail within the WCS Addendum.

We acknowledge that section 2.4 clarifies the challenges at some Waste Water Treatment Works (WWTW), particularly around phosphorous limits, due to: growth and/or climate change effects, and the limitations of the WCS (2025).

Some of the proposed strategic sites fall within some of these WWTW catchment areas.

The addendum generally appears to demonstrate a heavy reliance on AWS’ DWMP to provide solutions to accommodate growth in the more challenging locations.

As set out in paragraphs 2.4.6 and 2.4.7, whilst the WCS does not conclude that the pattern of growth is unsustainable in these locations, it does indicate that that “…only on completion of detailed plans can unqualified assurance of feasibility be provided. This is a consequence, in part, of relatively large growth across a natural water catchment with modest river flows.”

We are uncertain as to what is meant by ‘detailed plans’. If this is meant to refer to the DWMP, then we suggest that DWMPs are not currently ‘proven’ and solutions may not be practical or forthcoming at the desired time (e.g. technical reasons or funding not aligning as desired). It will remain important for yourselves to continue to work closely with AWS over the Plan period to ensure the DWMP can be updated where required, and any potential issues can be identified early on; as annual reviews of a DWMP by the relevant water company are now a statutory requirement.

We would conclude that, whilst the presentation of additional assessment and information within the Addendum does not go as far as we would normally recommend at this stage, we are satisfied that the WCS can be kept up to date as more information becomes available.

We are satisfied to be able to recommend that the WCS evidence base, as it pertains to wastewater, can be considered sound on the basis that there are strong Policy and future infrastructure planning measures in place to manage potential risks, but we wish to set out the following caveat advice around environmental risk.

Should any growth come forward for delivery in the interim, ahead of the updated DWMP, or development phasing trajectories are unable to be aligned with WWTW investment upgrade plans thereafter, then there remains some degree of uncertainty regarding any potential risk of harm to water bodies from growth within the associated to the WWTW catchments facing capacity challenges, in the absence of more detailed strategic assessment at this stage. Therefore, we would refer to the positive wording of Policy CC/IW and the Water Quality section, which requires the capacity for waste water treatment to be demonstrated prior to occupation of development and ahead of any respective phases if applicable. In such circumstances, it may be pertinent for further assessment at the site-specific stage of planning to be undertaken to manage risk to the water environment and inform decision making, as well as potentially justify phasing condition approaches.

To assist with understanding the individual circumstances associated with specific WWTW catchments, we have currently developed environmental position statements for two of the key WWTWs within the GCSP Local Plan area; Cambridge and Uttons Drove. The latest versions of these documents can be found attached to our representation. The Cambridge WWTW position statement (version 6) has been updated since our previous Reg 18 engagement, and the Uttons Drove WWTW statement (version 2) is newly developed. We will continue to review and update these statements regularly, as well as consider the need for position statements in other WWTW catchments, as our understanding of available information and evidence evolves.

This policy lists factors to consider for development of airfields. Land contamination should be considered, particularly PFAS contamination as a major potential risk to the groundwater environment. Contaminated Land Assessments should be completed, as per guidance linked in Policy WS/HS: Pollution, health and safety. Further detail on the importance of this topic is available on the CL:AIRE PFAS Site Profile (01).

We believe this evidence document to be sufficient at this stage of the plan process. As stated in our precious response, we would recommend that the plan is updated throughout the lifetime of the Local Plan Period to ensure assumptions around delivery of wastewater infrastructure are still valid.

We note the plan places heavy reliance on Anglian Water Services’ (AWS’) next Drainage and Wastewater Management Plan (DWMP) (2030-2055) to deliver the required infrastructure upgrades needed to meet the planned growth. The DWMP should enable delivery of infrastructure at key moments, but you may need to provide AWS more detailed phasing information over the plan lifetime so they can apply for relevant funding to accommodate upgrades in good time.

Concerning Uttons Drove, which is listed as a Critical Priority in Table 8-1 (Summary of Strategic Wastewater Projects): The Greater Cambridge Integrated Water Management Study – Detailed Water Cycle Study (October 2025) sets out that Uttons Drove is already exceeding its permitted Dry Weather Flow. Section 2.6 of the Water Cycle Study Addendum (2026) provides further information as to the challenges of increasing treatment capacity at this location to regain compliance and accommodate the planned growth. Whilst we expect that the DWMP will include an assessment of those challenges and provide information on what can be done, this may lead to some delay in initial upgrades being completed, or alternatives being in place (i.e. after 2030). Phasing of development to align with capacity availability (and thus Policy CC/IW) will therefore be very important in this wastewater catchment area.

We note that Policy I/EI: Energy infrastructure masterplanning, mentions the possibility of battery storage facilities. Where Battery Energy Storage Systems (BESS) are developed there is potential for pollution of the water environment in the case of emergency situations, in particular fires. In the event of a fire, highly polluting chemicals in batteries could present risks to groundwater and surface water in firewater or rainfall via surface water run-off. We recommend that the policy requires that applicants should ensure mitigation is in place for containment of this water and propose appropriate mitigation measures. Applicants should assess risks to groundwater and consider whether BESS battery containers should be located away from vulnerable receptors.