BT1504 The Vale Cemetery and Crematorium flood investigation

<p>Please note there are Three Phases to this project and there may be the opportunity for further work once the three phases are complete although there is no guarantee. SPECIFICATION FOR The Vale Cemetery and Crematorium flood investigation Is this specification for goods, works or services? Services Is this a technical conformance specification OR outcome and performance? Outcome and Performance Introduction Luton is a large and growing town around 30 miles to the north of London. Luton Council (LBC) is a unitary authority covering an area of approximately 16.74 square miles (43.35 km2) and the current population of Luton is estimated at 216,000. LBC employs approximately 3,000 people based in a variety of locations such as offices, schools, nurseries, crematorium, parks pavilions, community centres, sports centres, day care, residential, police station, hospital, etc. These locations are located across the Borough. LBC in its role as a Lead Local Flood Authority (LLFA) is responsible for managing flood risk locally. In the 2015 Local Flood Risk Management Strategy LBC set the following aim: &ldquo;To enable the management and communication of the risks and consequences of flooding arising from rivers, surface water runoff and groundwater in the borough of Luton&rdquo;. One of the objectives to achieve this is: &ldquo;Improve the Understanding of Flood Risk in Luton&rdquo;, and is facilitated through the &ldquo;Investigation of flooding incidents&rdquo;. In response to flooding at The Vale Cemetery and Crematorium over winter 2020/21 and in October 2021, LBC is seeking consultancy support to identify, assess and mitigate flood risk at The Vale Cemetery and Crematorium in Luton. Specifically, support is required to conduct a three phased investigation into the flooding on site. The outcome of the tender will be: 1. A comprehensive section-19 style technical report that assess the flood events of Winter 2020/21 and October 2021 (and previous instance of flooding) and makes &ldquo;adaptive&rdquo;* drainage measure recommendations for future mitigation. 2. Modelling and refinement of the proposed &ldquo;adaptive&rdquo; drainage recommendations 3. Detailed Designs for the leading &ldquo;adaptive&rdquo; drainage recommendation. *Adaptive - a dynamic approach to risk management, known as an &lsquo;adaptive approach&rsquo;, planning for a range of future scenarios in climate, growth and other uncertainties so the capacity to adapt is built in to the proposed measure (s). Section 1: Background &amp; Context LBC is committed to mitigating flood risk to people, properties and infrastructure within the borough. A Surface Water Management Plan (endorsed by the LBC&rsquo;s Executive Committee in 2011) and Local Flood Risk Management Strategy have identified objectives to manage flooding and communicate risks locally. More recently, the Resilient and Adaptive Communities strategy, which aligns to the Luton 2040 vision and supports the strategic priorities of LBC (See appendix B) as well as the Thames Flood Risk Management Plan, has been supported by the senior leadership team in 2021. LBC wishes to appoint a suitably qualified consultant to deliver a comprehensive section-19 style technical report for the LLFA, in respect of flooding at The Vale Cemetery and Crematorium in Luton that occurred principally on the 21st January 2021 and 20th October 2021. The investigation should explore previous instances of flooding, propose &ldquo;adaptive&rdquo; options for drainage at the site and provide linkage to two subsequent phases of work &ndash; Modelling and Refinement and Detailed Design Development, as detailed in Section 2. The consultant must demonstrate that they&rsquo;re able to mobilise quickly (within 15 working days of award) to start the initial phase, commence subsequent phases (after project managers have instructed to do so), and if further flooding has been experienced at The Vale Cemetery and Crematorium in Luton. Section 2: Service Requirement The selected consultant must provide: 1st Phase Initial screening (within 15 working days of contact award): a mostly desk based review (with 1 site visit) to provide a comprehensive, technical report that assesses the flood events of the 21st January and 20th October 2021 (and previous instances of flooding) and makes &ldquo;adaptive&rdquo; drainage options recommendations for future mitigation. The technical report should provide a reasonable level of information and detail on the following: a) The flood mechanisms in the affected areas, including type, location and source of flooding/ combination of flooding from multiple sources, to provide a review of the flood events. Must look at the wider contributing water catchment; including ponds, formal/informal field drains and highway drainage*. b) Existing flood/drainage infrastructure and the performance of this in the flood event, including limitations or identified weaknesses. c) The appropriateness of a range of options that aim to mitigate or alleviate future flooding, such as carefully targeted further studies and/or more detailed hydraulic modelling. d) Where the feasibility of any proposed &ldquo;adaptive&rdquo; drainage measures needs to be confirmed, recommendations should be made for LBC and/or other relevant body to undertake a more detailed study to confirm acceptability in principal of the potential solutions. e) Opportunities for collaborative work with partner organisations, developers and the community to improve local understanding of the flood risk and how to take measures to increase resilience and preparedness for flooding in the future. f) Clear and evidenced guidance to assist the LLFA, local residents, councillors, stakeholders, agencies, designers and planners on understanding the risks to and from the area. g) In consultation with stakeholders (1x 2hr meeting), agree options to be progressed to 2nd phase. *Where topographic survey is required to support the project the consultant is responsible for specifying and procuring this. Budget estimate for that should be clearly stated. 2nd Phase (Modelling and Refinement): Mostly desk based assessment (with 1 site visit) to refine and provide modelling of the Vale catchment to verify the findings from the 1st phase initial assessment. This investigation must: a) Model the wider catchment and newly installed drainage at the North-Western section of the cemetery, and assess its performance and conveyance of the 1 in 100 rainfall event + 40% Climate Change. b) Model proposed &ldquo;adaptive&rdquo; drainage options as identified under 1st phase initial screening. c) Fully itemised breakdown of the detailed design and construction costs of the options. d) Short technical statement detailing the methodology, data, any assumptions and maintenance requirements. e) In consultation with stakeholders (1x 2hr meeting), agree the preferred option to be progressed to 3rd phase. 3rd Phase (Propose detailed designs): Mostly desk based assessment (with 1 site visit) to prepare detailed designs for the leading drainage option. Key outcomes must include: a) Detailed designs of proposed &ldquo;adaptive&rdquo;* drainage for The Vale Cemetery and Crematorium that complies with design principles of CIRIA C753 SuDS Manual. b) In consultation with stakeholders (1x 2hr meeting), agree the preferred option to be taken forward to construction. *Adaptive - a dynamic approach to risk management, known as an &lsquo;adaptive approach&rsquo;, planning for a range of future scenarios in climate, growth and other uncertainties so the capacity to adapt is built in to the proposed measure (s). 2.1 Nature of commission In response to the invitation to tender, the supplier must demonstrate that they are able to mobilise quickly - within 15 working days of award - to start the 1st phase; and after project managers have decided to commence subsequent phases; and in the event that further flooding occurs at the Vale Cemetery and Crematorium in Luton. Further requirements may be identified in addition to or replacing those identified in Section 2 therefore consultants should consider this in their responses. It is very important that responding suppliers provide: 1. A detailed cost breakdown for each phase 2. A schedule of rates for ad-hoc site visits/ in person meetings* 3. For a degree of scope creep should further flooding occur *Subject to COVID restrictions Project managers reserve the right to cancel or delay phases 2 and 3 should other factors impact on scope for the works. Section 3: Budget/Spend Information It is important that responding suppliers provide: 1. A detailed cost breakdown for each phase identified in Section 2 Service Requirement 2. A schedule of rates for ad-hoc site visits/ in person meetings Section 4: Performance Measures Weighting Quality Understanding of specification Detail of methodology Examples of previous work 50% Cost 50% Ability to meet the requirements With reference to the requirements stated in the specification, please describe your understanding of the requirements. (Word limit: 500) Detail of methodology Please describe the methodology you propose using to successfully carry out this work. Your response should indicate a clear methodology with defined stages and outputs. (Word limit:500) Evidence of delivery of similar projects Please provide examples of similar recent work, especially with other local authorities (please provide at least one reference), clearly state any subcontractors if used/intending to use. (Word limit: 500) Team and staff expertise Please outline your project team, detailing the specific skills and knowledge they bring to the project and the roles which they will fulfil in the project delivery. Please only provide examples of relevant experience and qualifications linked to supporting delivery of your approach, full CVs are not needed. (word limit: 1,500) Section 5: Timescales The commission is expected to start 10th January 2022 and the duration of the 1st phase will be approximately 1 &frac12; months (until mid-February 2022). Total phases are outlined below: 1. 1st Phase Initial screening &ndash; start within 15 working days of award 2. 2nd Phase (Modelling and Refinement) &ndash; 3. 3rd Phase (Propose detailed designs) &ndash;2nd and 3rd Phases timescales to be determined by project manager with agreement from consultant as the project progresses. Weekly update will be required throughout the project with the exact form (eg calls, meetings, written submissions, presentations) to be agreed and is subject to COVID restrictions . As mentioned in Section 1 Background, the consultant must demonstrate that they&rsquo;re able to mobilise quickly (within 15 working days of award) to start the initial phase, and commence subsequent phases (after project managers have instructed to do so), and if further flooding has been experienced at The Vale Cemetery and Crematorium in Luton. Section 6: Appendices Appendix A &ndash; Overview of recent flooding incidents (please note this is subject to updates) The full extent of the flood events on the 21st January and 20th October 2021 remains unknown. EA&rsquo; s Water Situation Report indicates that prolonged rainfall fell in the region in Winter 2020/21: 282% of LTA rainfall in October 2020; 146% of LTA in December 2020 and 175% of LTA in January 2021. This continuous period of above average rainfall caused flooding to the North-West section of the cemetery in early January 2021. On the 21st January 2021, a 1 in 1 year RP event exacerbated flooding in the cemetery and caused flooding to Butterfield Green Road. In January 2021, in order to mitigate the flood risk to the cemetery, a temporary ditch was excavated and sandbag/soil bund erected on the northern boundary of the cemetery to intercept the flow path entering the site from the adjacent field. This ditch required pumping out daily by tanker in order to stop overtopping and further flooding. In mid-March 2021, the pumping out frequency was reduced and water levels in the ditch receded as the weather improved. In September 2021, a permanent drainage solution (see Appendix A) was designed for this section of the cemetery which included a number of French drains with perforated pipes leading to a soakaway and overflow balancing pond. Construction of the proposals began early October 2021 with an approximate completion date of early 2022. Some of the proposed French drains are unviable given the close proximity to graves dug post design development. Rainfall data suggests the week leading up to 20th October 2021 was a dry period (relative to Winter 2020/21), followed by a 1 in 10 yr RP event on the 20th October 2021 that filled the temporary ditch - almost overtopping the bund. Localised flooding was observed in areas of the cemetery but it was not as widespread as in Winter 2020/21. The ditch and bund provided flood risk mitigation during this event but required pumping out in case of subsequent storm events. It is not known if drainage has been designed in prior to these storm events and the use of this section of the cemetery. In addition, the inability for water to drain in the area is further compounded by a clay geology (to approx.10m BGL), graves being surrounded by a concrete encasing (traditionally Islamic method) and compacting caused by machinery servicing the area. It has also been speculated in local media it is caused by increased usage due to COVID-19. Considering the potential wider-catchment area for the Vale Cemetery and Crematorium, LBC would like to commission a single investigation to understand the surface water flow paths, water storage requirements and potential &ldquo;adaptive&rdquo;* drainage measures to mitigate flood risk in the future. The investigation must recommend &ldquo;adaptive&rdquo; flood risk mitigation measures for future flood events at the site. *Adaptive - a dynamic approach to risk management, known as an &lsquo;adaptive approach&rsquo;, planning for a range of future scenarios in climate, growth and other uncertainties so the capacity to adapt is built in to the proposed measure (s). Appendix B &ndash; LBC Strategic Priorities Everybody in Luton, including residents, our community and public, private and voluntary sector organisations, will work together to deliver on the following strategic priorities to achieve our shared vision. &bull; securing a strong economic recovery from COVID-19, which protects jobs, incomes and businesses and enables us to build a more inclusive economy &bull; protecting the most disadvantaged in our town by prioritising service sand interventions that focus on prevention, alleviate the impact of poverty and reduce health inequalities &bull; making Luton a child-friendly town, where our children and young people grow up feeling happy, healthy and secure, with a voice that matters and the opportunities they need to thrive &bull; becoming a greener and more sustainable town, to meet our long-term ambition to be carbon neutral and climate resilient by 2040 &bull; a strong and empowered community supporting fairness, equality and local pride and speaking with a powerful voice</p>