Warren Crescent 10 House Development – Risky, Reckless and Ruthless

The Warren Crescent Housing Development – Risky, Reckless and Ruthless

Isn’t This Worth Saving?

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Fig: W1: Warren Meadow – To Be Destroyed By a 10 House Development
Lye Fen In Summer
  • Headington Heritage Lye Valley Headington Warren Crescent Development www.headingtonheritage.org.uk/lyevalleyruin Oxford Headington headingtonheritage.wordpress.com/lyevalleyruin
  • Headington Heritage Lye Valley Headington Warren Crescent Development www.headingtonheritage.org.uk/lyevalleyruin Oxford Headington headingtonheritage.wordpress.com/lyevalleyruin
  • Headington Heritage Lye Valley Headington Warren Crescent Development www.headingtonheritage.org.uk/lyevalleyruin Oxford Headington headingtonheritage.wordpress.com/lyevalleyruin
  • Headington Heritage Lye Valley Headington Warren Crescent Development www.headingtonheritage.org.uk/lyevalleyruin Oxford Headington headingtonheritage.wordpress.com/lyevalleyruin
  • Headington Heritage Lye Valley Headington Warren Crescent Development www.headingtonheritage.org.uk/lyevalleyruin Oxford Headington headingtonheritage.wordpress.com/lyevalleyruin
  • Headington Heritage Lye Valley Headington Warren Crescent Development www.headingtonheritage.org.uk/lyevalleyruin Oxford Headington headingtonheritage.wordpress.com/lyevalleyruin

Gallery F1: Rare Plants of The Lye Valley – Under Threat From Oxford City Council

Introduction

It is hard to think of a more environmentally destructive, reckless, ruthless, cruel, socially damaging and financially wasteful development managed with such overweening apparent incompetence than the still unbuilt 10 house development at Warren Crescent, Headington on the Lye Valley slope.

Click here to go to new content re land instability SUDS location (14/08/21)

Overwhelming evidence has been presented that the scheme is simply not fit for purpose, yet the Council persists in pursuing it against all logic.

In NEWLY uncovered evidence, (18/08/21) a proposed access road (See updated SUDS section below) to the Churchill Hospital across Warren Meadow was rejected as:

The tip face is partly overgrown and with only the existing footpath and play area on the top appears stable. However, its stability is not considered to be adequate for the construction of the access road … (BGS 1973, 6.1)

So the simple questions are: Why didn’t the Council check the BGS web site before? More importantly: If the tipped embankment was not considered stable enough to support even a small road without massive earthworks to flatten it for support, how can it ever support 10 houses and a SUDS? Simply put, it can’t.

Clear evidence that the Lye Valley West Fen is, far from “cleared reeds”, now mostly restored and teeming with rare species, and was and is worthy of the highest level of protection has been ignored by The Council, which seems to have forgotten that even after granting itself planning permission under false premises, it still has a statutory duty to protect it.

Although advised by SDS Consultancy of the fundamental flaws in the SUDS system, pivotal in the grant of planning permission, Oxford City Council (OCC) is still proceeding with a damaging, defective, unworkable and largely pointless design that will rob residents of the last vestige of green space rather than face public scrutiny via a planning variation which would have forced the abandonment of the entire scheme and a very probable unresolvable objection by Natural England regardless of the design adopted. Natural England withdrew its objection based on the functioning of this SUDS system, and as this does NOT work, the scheme must be halted.

If we accept the logic of the Planning Officer below, if the SUDS cannot work, then Planning Permission, or discharge of conditions, were not correctly granted as this was the basis on which Natural England withdrew its objection.

Fundamentally, the SUDS cannot be built due to the issues described here, therefore the scheme is infeasible.

Further, it must provide a dignified and healthy environment for its citizens now, as COVID has taught us, more than ever.

Subsequently, at time of writing, repeated FOI requests have revealed OCC does not hold ANY detailed designs other than those released as part of the planning process, which, in particularly in the case of the SUDS, are not sufficient to progress with a build, therefore OCC CANNOT have done any risk assessment at all – at least of some of the final designs.

Planning has granted itself the right (At EABC 04/08/20) to make any changes it chooses without further reference or consultation, which given the unresolved and unresolvable issues below, this must be of the utmost concern as stated in my objection at the EAPC meeting.

Fundamentally, this scheme is reckless of the environment and ruthless towards citizens with NO access to private green space living in blocks of flats, and financially senseless, negatively impacting the delivery of housing, and places OCC at risk of damage both financially and reputationally in the event of environmental harm to the Fen.

The only honourable and logical outcome is for the Council to abandon this crazed scheme before any more damage is done and money wasted. 

Issues Summary

    • The development will interrupt the groundwater flows from the whole catchment to the West Fen, which the Council described as “reeds” so no meaningful risk assessment was undertaken
    • The site is ABOVE and ON, not near the Lye Valley
    • The Made Ground under the development and SUDS is dangerously unstable, presenting a danger of sudden slippage of land one which the houses and the SUDS depends also a clear H&S danger to workers on the site
    • Ongoing land slippage on the Made Ground in which the the SUDS will be built and supported
    • The almost complete removal of all land on which the SUDS will be built – its construction will involve the removal of the entire bank at this point and cause its collapse
    • The Council has ignored evidence of Made Ground(BGS 1973) ongoing slippage of 1.5m at the SUDS location – despite repeated requests to obtain the full survey results, now presented here, in addition to land slips into the Lye
    • NO ground stability report, and very few boreholes exist for the SUDS area although it is a very large, underground top heavy structure
    • The Council preferred to continue with a defective, and largely pointless SUDS system design and waste taxpayers’ money rather than resubmit to public scrutiny by a planning change, rendering the discharge of condition invalid as appears not to be based on only material considerations, but on fear of further public scrutiny 
    • Any danger to the adjacent apartment blocks has not been assessed (unknown) speculatively, the Made Ground may be there specifically to support them.
    • Ignores the rights of Town Furze estate tenants and Leaseholders who have legal right of way over the area, and are in effect paying for its enjoyment via rent and charges
    • Public Green Space is being taken from the Green Poor in blocks of flats with NO private space and privatised for the exclusive use of the new development, contrary to the Social Equality Act of 2010, leaving children to play in the road
    • The secluded and wild feel to the Lye Valley will be permanently defaced by highly visible buildings
    • The footpath on open Warren Meadow with its beautiful views of the Lye will be reduced to a back alley and then set back from the edge at the SUDS 
    • It reduces Oxford’s housing supply by wasting money on expensive and infeasible development rather than spending it efficiently on producing cheaper, and more, homes, any gain is far outweighed by the damage done
    • The lack of design overview and lack of public consultation is of deep concern, all current information must be released.

For earlier and more in-depth articles refer to Headington Heritage, Lye Valley Menu.

The Background

Oxford City Council (OCC) has granted itself planning permission to build 10 houses and an associated SUDS system:

13/01555/CT3 | Erection of 10 x 3-bed dwellings (use class C3) together with associated car parking, cycle and bin storage. Diversion of public footpath. (Amended plans and description) | Land East Of Warren Crescent Oxford Oxfordshire OX3 7NQ

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Fig O1: Warren Meadow – Pre-Development Overview
Fig O2: Warren Meadow – Post-Development Overview

Council Failure -West Fen Is Habitat!

PBA advised OCC that the West Fen was “reeds” so the flows from the development (West) side of the catchment did not matter:

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Fig R1: As Presented To The Council by PBA Associates (Ref: PBA, 16)
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Fig R2: Annotated With The Actual West Fen Habitat (Yellow to Left, Right, East Fen)

The SSSI designation (covering both Fen sides) and protection is as a SITE of Special Scientific Interest is to protect the fen environment.  

Its degraded state in 2013 was NOT relevant, and it was quite wrong to apparently suggest did not matter as it was not part of the “main fen” although it is approximately 50% of it, and then to claim that flows under the development were therefore not contributing to a unilaterally declared “Main Fen” on the East side of the Lye.

PBA marked the East Fen (Fig R2 right) as “an area of extensive fen habitat”, but the West Fen (left) as an “area of restoration reed” and “cutting scrub removal”. (Fig R1)  “Habitat” is that which supports fen flora not the flora itself – This was an ELEMENTARY error.  Even were this argument accepted, the West Fen is now home to many rare flora such as over 40 Marsh Helleborine orchids, and almost no reeds still exist.

Under pressure from the FOLV (Friends of Lye Valley), a hydrological assessment of the flows ON and FROM Warren Meadow was conducted,  but the focal role of the development site in the Lye Valley hydrology of flows UNDER AND THROUGH the West Fen from ALL of the west catchment was simply ignored. NO assessment of the crushing effects of 10,000s of tons of foundations on the delicate rock layers though which water flows was undertaken.

Groundwater Flows – Why They Matter

Rain falls in the whole catchment, infiltrates through limestone, and becomes vital calcareous groundwater on which the Lye Valley SSSI depends:

Fig F1: Catchment Flows (Blue) to the Development Site (Red) and Fen (Green)

This concentrates and flows UNDER the development site (Fig F1 Red) as shown with blue arrows, via a perched water table and layers of rock picking up the correct calcium content. Flows will be blocked as shown above (Fig F1)

Fig F2: Catchment Flows Through the Development Site (OCC)

It then emerges ABOVE the West Fen (Fig 3 Green) at the springline (Fig 3 Blue) as shown below:

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Fig F3: West Fen and Springline  (continues under Dev) – This is “Reeds” 

How The Development Affects Flows

Development Site – Pre 1956

Rain falls on the entire catchment infiltrating into the ground and down to the perched water table/aquifer. Importantly flows move both down and towards the viewer and the West Fen as shown in Fig F2.

For the section location below, see (Fig O2, B-B1/B’)

Fig D1: Development Site – Pre Development – Infiltration To Springs

Development Site – Warren Meadow – 1956 Approx

Fig D2: Warren Meadow From 1956 to Present

In approximately 1956, the builder’s rubble, (Made Ground) probably from site levelling for the Town Furze estate, was used to create Warren Meadow and an artificial and unstable slope ( brown line)

The natural Lye Valley slope (green) was covered with Made Ground (or Tipped Embankment), destroying almost all the fen below. Flows were weakened (not shown).

The flows moving towards the viewer and which emerge in the Lye under the development site.

This is the current situation.

Development – Warren Crescent Development – 2021

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Fig D3: Post Development showing aquifer crushing and rupture

The Warren Crescent development will require deep foundations (black) to reach the solid natural slope (green) of the Lye Valley at 1-3.5m below the artificial flat surface of Warren Meadow, requiring foundations to 4m+ for a level surface, this will sit directly ON and crush the underlying Beckley Sand Member, the aquifer on which the Fen depends for its groundwater.

This will be effectively a giant underground 80m * 20m dam corresponding to the blue outline shown in diagram above (Fig F1 – Catchment Flows Through the Development Site) blocking ALL flows from the ENTIRE west catchment

These impose massive weight on the delicate water bearing layers below, either rupturing them or crushing them so water is either blocked, or simply leaks below the level of the fen and is lost. 

The Access Road Report (BGS, 1973, 6.1) states the groundwater level appears to be in the natural ground just below the fill (Made Ground) indicating both that the weight of the foundations will impede the flows as the foundations are built into the natural ground, and that the flows will weaken the foundations.

The West Fen, deprived of calcareous groundwater, will then die.

Made Ground – The Steep Slope

The artificial slope formed by the Made Ground to the Lye Valley is between 32-42 degrees, as measured by Dr Curt Lamberth and corroborated in the BGS report. (BGS)

[1] See also Fig V2: below for bank steepness at the housing area.

The Slope Stability report (GEO) determined the slope was dangerous to a point approximately 3-4m from the edge.  The nearest houses will be located within 8m from the cliff edge NOT 12m as stated (GEO2, 10)

The Access Road Report (BGS 1973, 6.1) (see SUDS below) states:

The tip face is partly overgrown and with only the existing footpath and play area on the top appears stable. However, its stability is not considered to be adequate for the construction of the access road 

and states the current steepness of just under 1:1 (<45 degrees) should be reduced to 1:1.75, or 29.6 degrees (1/1.75)=0.57, arctan(0.57)=29.6) by placement of hoggin against the existing tipped embankment shown above.

Significantly, a proposed access plan in 1978 showed three routes, NONE of which was the crest route across Warren Meadow, implying it was considered infeasible.

Council Failure Summary – Slope Next To The Houses

The stability report (GEO) failed to address:

      • The excavation disturbance which will be far greater, and nearer to the edge, than the final foundation footprint
      • Damage to tree roots at the cliff edge caused by contaminated soil removal and replacement, coppicing, and tree removals causing further instability is unassessed
      • Groundwater from the original spring-line seeping under the foundations, undermining the bank
      • The effect on the land being split between the foundations and the cliff edge, which will become unstable
      • Evidence of previous landslips (See SUDS below)
      • The H&S risks to construction workers
      • Critically, it did not address the slope stability at the SUDS location, only at the housing development. (see below)
      • That a slip here would bury the Lye Brook, destroying the Fen

It is sheer folly to rely on trees to maintain the structural integrity of the bank.

The unstable part of the bank in front of the houses is shown below (orange hatching), before and after a landslip, which could include the houses themselves (not shown)

Fig D4: Post Development With Unstable Ground

Fig D5: Post Development After a Landslip

The SUDS

A SUDS (Sustainable Drainage System) is designed to retain water to prevent downstream flooding and mimic the natural drainage environment.

The SUDS – Council Failure Summary

      • Failed to investigate the BGS 1973 finding of 5.5/6.0m depth of Made Ground at the site, despite repeated warnings, which shows ongoing land slippage and instability
      • It does NOT mimic natural flows, instead concentrating all flows to one point at the headwall of the SUDS, starving the West Fen of groundwater
      • It will be dangerously unstable leading to bank collapse both due to leakage and pressure on slipping Made Ground from a top heavy unsupported structure of which very little will be left on the valley side for structural support
      • 90% of it is completely pointless as flows will never reach it
      • It does not regulate the pH of the groundwater which is key to Fen survival
      • Will discharge into polluted Made Ground which will release chemicals into the Fen 
      • It is unmaintainable due to poor design
      • Deprives residents of desperately needed green space for NO gain
      • Has a completely pointless bund, adding to the instability of the slope
      • It is dangerous to build, creating serious H&S issues
      • May block flows directly as the structure will be “keyed in” to the original slope which is AT the water table level at this point (approx  89-90m AOD) ON the Beckley Sand Member aquifer strata layer
      • May compromise the structural integrity of the adjacent 33-55 Warren Crescent block of flats (unknown)
      • Coppicing to keep the SUDS free of leaves, and removal of trees will weaken the bank, and make housing (33-55 Warren Crescent) visible from the Lye Valley
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Fig S1A: The Pointless SUDS Area – Precious Green Space 
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Fig S1B: The Pointless SUDS Area – Replacing the Last of the Green Space 

The intended SUDS structure (PBA/SDS) is shown below – it comprises of 60m of limestone length, 1m thick at its base, spreading out in a V shape as shown below which will be supported by the Made Ground and the water bearing underlying Beckley Sand Member aquifer.

Stormwater from the development will enter at the head (right side), and in theory flow via a series of dams, and gradually leak via the base, flowing over limestone rocks to provide calcification and then in to the aquifer below.

The photos above are from the head of the SUDS or looking from right of the blue dot below, to the left:

Fig S2 – SUDS and Design Defects (©WSP Annoted)

Fig S3: SUDS – Unstable Made Ground After SUDS implementation (As at Fig S2 S-S1)

Council Failure -SUDS is on Slipping and Unstable Made Ground

In 1973, the Churchill Hospital commissioned a report (BGS 1973) to look at two new alternative potential routes for an access road, the western route, via the Warren Meadow development site, and the eastern route via the Lye Valley, as shown below:

  • Lye Valley Headington Heritage
  • Lye Valley Headington Heritage
ReferenceNameLength (m)Made Ground
SP50NW213BH152.85m
SP50NW214BH240m/0.75m
SP50NW215BH3153.25m
SP50NW216BH4135.5m/6.0m
SP50NW217BH5152.85m
SP50NW218BH652.7m
SP50NW219BH750m
SP50NW220BH850m
SP50NW221BH950m
SP50NW222BH1050m
SP50NW223BH1150m
BGS Survey 1973 – BH1-BH6 are the Western Route (Brown)

[1] 5.5/6.0m indicate possible ranges/interpretations – see Borehole Logs.

[2] BH2 is incorrectly marked as 0/07.5 on plan, this should read 0/0.75m as per table above.

The following images show the orange cone (BGS SP50NW216/BH4) which correspond to the blue dot in Figure S2 SUDS Design and Defects above then BGS SP50NW215 BH3 which indicates 3.25m of Made Ground at the end of the meadow.

A comparison of BH4 (BGS 1973) and borehole WSP WS105 2018 (WSP, 2/2, App C p55 PDF, Map PDF p.33, 2018) shows a ground level drop over time from 95.3m to 93.9m or a 1.5m drop (rounded).

The two boreholes are a maximum of 2m from each other based on the maps and coordinates given. The 1954 Map shows a shallow slope here, so are comparable even if not precisely in the same spot.

The following images shows two groupings of boreholes BH4 and WS105, and BH3 and BH105 from the two surveys (BGS 1973 (Green), WSP 2018 (Brown) for comparison over time, and overlaid with the 1954 Estate Map to show the land surface in approximately 1954.

The borehole comparison for the two surveys in the three images above shows:

    • The ground level in 1973 at BH4 (Green) was 1.5m higher than it is today (Brown)
    • Made Ground at BH4 was 5.5/6m deep in 1973, but only 3.2m in 2018 (WS105). 5.5m-6.0m is marked as “Fill” 
    • In 1954 (Map 1954) the ground already had 3.2m of Made Ground (BH4/WS105), which was added to later (Purple)
    • The 1973 Ground Level (BH4,95.3m) was higher than the current Warren Crescent Road (95m), probably as it was built up and expected to compact
    • The original Made Ground surface was probably mostly flat, not sloped towards, and down, the Lye Valley as today
    • The Beckley Sand Member (BSM), the aquifer, is directly below Made Ground, indicating compression here will directly impact on flows and lead to soil erosion

Crucially, the Council failed to check for any prior ground surveys which would have, in less that five minutes on the BGS Web Site have indicated the land is not suitable for development despite repeated requests to do so

Compaction of Made Ground would have reduced the Ground Level, but the most likely explanation for the 1.5m drop at BH4, given the now sloping nature of the SUDS area, is that the ground is eroding due to Made Ground being dissolved by the hydraulic action of streams and seepages running underneath, so far over 25% (1.5m/6.0m) has been lost in 45 years. (1973-2018)

The deeper levels of the Beckley Sand Member (BSM) and the Made Ground Base indicates that BH4 was probably closer to the edge than WS105. (possibly a little to the left of the cone shown above)

A similar pattern is seen at BGS SP50NW215/NWBH3 and WSP BH105 with a drop of 0.5m in ground level from 93.6m to 93.1m Ground Level, and reduction in Made Ground from 3.25 to 1.9m. This is consistent with some local loss of land being compensated by losses from higher upslope. The boreholes are not as close as the first set and are not so closely comparable with 1.25m difference in bedrock level.

The Beckley Sand Member, present DIRECTLY below the Made Ground, on which the SUDS must be supported, is an important aquifer for the Fen:

The Corallian beds are permeable and result in a series of minor and perched aquifers including Beckley Sands and Wheatley Limestone. The base of the Corallian located above the impermeable Temple Cowley Member gives rise to a series of springs at or just above the boundary between the Beckley Sands and Temple Cowley Member clays. This spring line is responsible for a number of minor springs around Headington Hill including Boundary Brook and Lye Valley. (TWU 26)

Council Failure – Evidence Of Previous Landslips Ignored

Clear evidence of a previous landslip directly below the SUDS is shown below, showing the extent of the slip and its affect on the fen.

This landslip buried sewer inspection hatches which are known to be in this area, this implies strongly this occurred after the tipped embankment formation in the 1950s.

Climate Change Increases Probability of Collapse

Events since grant of planning permission in 2016 have indicated clearly that we are living a period rapid climate change, a key feature of which is the greater carrying capacity of the atmosphere, leading to periods of intense rainfall, with records being broken.

There cannot be a more reckless place for a housing development in these circumstances than on top of a tipped embankment with a streamline running directly below it, weakened by underground structures such as the SUDS.

IF, as appears increasingly possible, a major storm event occurred, the weight of the water, the unstable V build structure, the weakening of the foundations by discharge underneath and support from weak, Made Ground, would almost certainly result in its collapse into the Lye Valley. The structure is in effect designed to weaken the ground underneath it.

In summary, the Made Ground will collapse due to:

      • Pressure from the imposition of a top heavy structure on very deep Made Ground with an artificially steep slope are shown above.
      • Excessive removal of almost all the Made Ground to form the SUDS   
      • Root damage due to the SUDS construction extensive coppicing required to keep the entirely pointless SUDS free of leaves, and imposition of the entirely pointless bund
      • The SUDS outfall as above weakening the structure.
      • Existing streams at the base of the structure constantly dissolving earth, leading to loss of support from the surrounding ground
      • Severe storm due to global warming causing increased underlying flows, adding weight due to the contained water and washing away very disturbed Made Ground

The ground stability report (GEO) only investigated the area in which the houses are to be built, NOT the SUDS area.

The Council failed to consult the 1973 report (BGS) despite repeated requests to do so. Instead it commissioned several expensive ground surveys but with few boreholes at the SUDS location.

This report indicates clearly that a SUDS here would be an unstable top heavy structure, “supported” by slipping Made Ground, pushing on to a steep, artificial slope. Its weight will crush the aquifer (BSM) directly below.

PUT SIMPLY, IS IS NOT POSSIBLE TO BUILD THE SUDS

Failure – The SUDS Does Not Mimic Greenfield Runoff

The originally approved SUDS design was produced by PBA who stated:

The “proposed permeable paving and swale has been designed to mimic the existing greenfield drainage regime” (PBA)

Fig S4: SUDS – Showing pointlessness of remaining SUDS (© WSP, PBA Annotated)

This was reviewed by SDS (4980-RP01) as part of the Planning Condition 11 discharge, who observed:

SDS note that surface water flows are to enter the swale and disperse over the first erosion control mattress. This entails that surface water flows will discharge directly into the underlying limestone fill and essentially flow along the length of the sub surface of the swale. It is unlikely that surface water flows will discharge along the length of the swale due to the direct discharge into the limestone beneath the swale thus making the implementation of the swale redundant….

No flows occur the length of the swale. The swale will only have water within the swale due to the back of flows from the sub base limestone, this occurs during the 1:100 year storm events.” (Ref: SDS)

To put it more bluntly, 95% of the SUDS is pointless. (S2 purple, 50m long) and does not achieve the stated aim, the only reasonable explanation for proceeding with a defective or at least redundant design as reported by SDS, on valuable green space appears to be the reluctance of the Council to have to justify the unjustifiable as part of a new Planning Variation which would subject the risk to the Fen to public scrutiny – these grounds would NOT be a material consideration in planning law making planning approval in effect invalid.

So the SUDS will achieve the exact opposite of natural, diffuse infiltration of rainwater, and ensure most runoff from rooves and the estate is concentrated at the headwall of the SUDS where it discharges vertically (S2 blue, S4 blue) so water flows directly down through the artificial limestone bed of the SUDS and falls down in a concentrated manner 100m from where it is needed at the West Fen.

This water is far less likely to percolate along part of the perched water table as it will create an erosion channel and small spring, or will infiltrate directly down to the Lye Brook level below, reducing the flows to the West Fen, and causing a landslip as advised:

Consideration should be given to the drainage of the proposed development, additional or concentrated discharge of water in close proximity to the slope should be avoided. The use of soakaways in the rear gardens, for example, is inadvisable. (Ref: GEO 10)

This is exacerbated by complex geology meaning that water could arrive on either Beckley Sands or Limestone doggers and be lost.

It is equally unclear what purpose the bund serves other than to block one of the prettiest paths in Headington, it will never retain water, and even if it did, would probably contribute to the slope collapse due to its weight.

Council Failure – Will The Apartment Blocks Be Supported?

Entirely speculatively, the question must be asked if the Made Ground serves a function as a means of supporting the adjacent apartment blocks, and what will be the result of removing almost all the land directly behind them?

Council Failure – SUDS Maintenance Will Be Impossible

The design and depth of the SUDS, as pointed out by SDS :

Note that the current PBA / WSP design which gives a significant depth of limestone to the Beckley Sands does not consider future maintenance or inspections. … The PBA / WSP design entails that the full length and depth of the limestone would need to be removed and replaced in the event of a spillage / pollution incident”. (Ref: SDS, email)

Council Failure – No SUDS pH Regulation

Planning Officers emphasise the importance of the SUDS system to ensure the water is the right pH for the SSSI:

“The site is adjacent to the Lye Valley triple SSSI, an area of fen particularly sensitive to changes in water quantity, quality and also water chemistry/changes in pH. In order to maintain the correct pH, it is necessary for particular materials to be used, i.e. the limestone.” (Ref: SDS Planning Officer App B)

The SUDS is supposed to deliver calcified water of the correct pH to the fen, however:

      • It has no regulatory mechanism, so over or under supply of calcium and resultant damage to the Fen, is possible
      • There is no target pH given
      • No knowledge of the plant pH tolerances
      • No calculation indicating how specifically the SUDS would operate (noting that 90% of it is completely useless with only a very small part of the limestone actually wet)

SDS Consulting questioned the non existent requirements for the target design of the SUDS as below, Red is as in original text, not markup:

o What level of PH is to be achieved? Natural England Requirement? 

o What depth of percolation through the limestones needs to be provided to achieve the PH requirement (if evident that there is a requirement)? 

Natural England Requirement? (Ref: SDS Appendix B)

The underlying assumption that a bit of limestone will be a good thing is an intellectually lazy and unfounded assumption that finds no support in any of the documentation – it is astonishing this was not clearly addressed before any design work was conducted.

The SUDS – Its Importance For Planning Approval

The SUDS design was absolutely critical to the grant of Planning Permission by overcoming Natural England’s objection.

The importance of the SUDS system and concern about the damage to the hydrology of the fen is clearly set out by a Planning Officer to the applicant’s contractor:

“I appreciate that your client may be looking to reduce costs, [by presenting a better SUDS design] but there is a considerable history to this site, the planning permission, and even the allocation for housing which you need to bear in mind. There was considerable local interest in this site, and particularly the impact on the SSSI. This required a specific solution to ensure that the development did not impact on the hydrology to the fenn.[sic] There was a particular objection from Natural England to developing this site that was only removed once we agreed to allocate it for development in the Sites and Housing Plan and provide a caveat that a suitable drainage solution was provided. 

The application through pre and post application discussions developed a strategy which enabled the removal of Natural Englands objection to the planning application. Therefore we cannot accept changes which undermine the purpose of this strategy which amongst other things was to maintain the right level of PH of the water. 

This strategy was so integral to the scheme that the Council would not have obtained planning permission without it, and therefore we cannot accept changes to the strategy without a new application or at the least a formal application seeking variation of the condition. This will be subject to public consultation and will open up all the previous issues raised.”  (Ref: SDS, Appendix B, Planning Officer email)

That SDS found it necessary to include this and other email exchanges below between the Council and other parties would imply it was deeply uncomfortable with the “dictated” design imposed by the Council.

Failure – The Wrong SUDS Design Has Been Approved

The design contained in the SDS Report was accepted as an approved SUDS as discharge for condition 11.

At the EAPRC Planning Committee meeting of 05/08/20, Planning asked for permission to alter plans for the footpath only and produced this presentation however it appears the footpath was added to the WRONG version of the SUDS system.

This is the REJECTED design supplied by SDS referred to in the blog (Issue 1). It is currently the accepted plan!

Failure – Green Space

The Footpath

A delightful footpath (SP80) runs across the site, officially, diagonally across the development, but in reality along the treeline.

Headington Heritage Lye Valley Warren Crescent Development www.headingtonheritage.org.uk/lyevalleyruin Oxford Headington headingtonheritage.wordpress.com/lyevalleyruin
Fig: P1 One of the Prettiest Paths in Headington Part of the Lye Valley Network

This footpath will be retained as a “permissive” path, but boxed in by rear gardens, losing the open feel.

This is currently subject to a planning inquiry re the footpath “diversion” (removal) with objections to be lodged by March 9th 2021 – email author for details. See this article.

Removal Only Useable Green Space

The housing development and SUDS system will result in NO usable remaining green space, where residents can enjoy the basic dignity exercising, relaxing or playing on ANY grassed surface – it will entirely fenced off depriving the local community of even a tiny vestige of remaining green space.

Most in the local community have NO access to private green space, living in the blocks of flats on the estate, leaving local children, including those from the development’s 10 “Family Homes” to play on the roads.

The alternatives to Warren Meadow, except for a tiny tots playground on polluted Girdlestone Road are shown below:

Headington Heritage Lye Valley Headington Warren Crescent Development www.headingtonheritage.org.uk/lyevalleyruin Oxford Headington headingtonheritage.wordpress.com/lyevalleyruin
Fig P1: Play equipment stripped out
Headington Heritage Lye Valley Headington Warren Crescent Development www.headingtonheritage.org.uk/lyevalleyruin Oxford Headington headingtonheritage.wordpress.com/lyevalleyruin
Fig P2: Entrance to only useable green space – intimidating and dangerous
Headington Heritage Lye Valley Headington Warren Crescent Development www.headingtonheritage.org.uk/lyevalleyruin Oxford Headington headingtonheritage.wordpress.com/lyevalleyruin
Fig P3: Only green space available – devoid of equipment with a dangerous entrance

Contrary to the Social Equality Act 2010, this development represents the transfer of public green space from the green space poor to create a new class of green rich who will have private gardens at the expense of the rest of the community to maximise Oxford City Council’s financial position.

Failure – To Respect Legal Land Rights

The tenancies and Leaseholds on the Town Furze estate certain rights guaranteed under the Housing Acts and listed in the Title (Land Registry – ON26151) – essentially these rentals or leaseholds pay not only for the individual property/flat, but also for enjoyment of the surrounding land (premises, facilities or services) which the Council are now stealing to give to new housing:

Under the Housing Act:

Where the dwelling house is a flat and the tenant enjoyed, during the secure tenancy, the use in common with others of any premises, facilities or services, the lease shall include rights to the like enjoyment, so far as the landlord is capable of granting them, unless otherwise agreed between the landlord and the tenant

No such agreement has been entered into.

This specifically referred to in the title here and elsewhere:

12   The Leases specified in the Schedule of Leases annexed which were made pursuant to Chapter 1 of Part 1 of the Housing Act 1980 took effect with the benefit of and subject to the easements and other rights prescribed in paragraph 2 of Schedule 2 of that Act.

Views from the Lye Valley

The sequestered and secluded feel to the Lye Valley, where it is possible to imagine you are no longer in a big city, with housing almost entirely set back from the Lye will be permanently destroyed:

Headington Heritage Lye Valley Headington Warren Crescent Development www.headingtonheritage.org.uk/lyevalleyruin Oxford Headington headingtonheritage.wordpress.com/lyevalleyruin
Fig V1: Pre Development – Note Steep Slope
Headington Heritage Lye Valley Headington Warren Crescent Development www.headingtonheritage.org.uk/lyevalleyruin Oxford Headington headingtonheritage.wordpress.com/lyevalleyruin
Fig V2: Post Development Destruction of the Lye Valley Seclusion (Calculated)

In addition, coppicing of trees opposite the SUDS will make the three storey blocks of flats visible from the Lye (33-55 Warren Crescent)

Negative Impact on Desperately Needed Housing

Oxford has a housing crisis – this ill thought out, very expensive, environmentally unfriendly, socially destructive project is diverting money that can be better spent elsewhere. How many Oxford families will go homeless due to the money wasted here?

The Site Plan Is Unrepresentative

Throughout the entire Planning Permission phase of the development, the Swale (SUDS) was presented (including at the Committee meeting of 05/08/2021) as being an irregular pond sown with wildflowers:

Fig L1: Plan Presented until Aug 2020

The SUDS diagram 7512-D-01 (WSP) accompanying the Condition 11 documentation shows that only a small section at the top will be water filled. SDS states it will never fill with NO water.

Neither the pretty pond or the SUDS system would EVER hold water except for very limited timeframes, so the portrayal of both these a water features is entirely unrepresentative.

Conclusions

It is perfectly clear from the evidence presented above that continuing with a scheme would be environmentally inexcusable, financially ruinous and structurally unviable, the Council must immediately halt this crazed scheme and let Warren Meadow be part of the Lye Valley for the enjoyment and recreation of citizens now and the time to come in an increasingly crowded city.

Appeal

Please Join Friends Of Lye Valley (FOLV) to help save this precious place:

Web:    http://www.friendsoflyevalley.org.uk
email: friendsoflyevalley@yahoo.co.uk

Author

Mark


Headington Heritage, A personal blog

Saving Headington’s Heritage
 
Visit  : www.headingtonheritage.org.uk

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Email: headingheritage@outlook.com

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Acknowledgements

The contents of this article are the result of input from many people, I do not claim the work to be my own.

Thanks for proof reading and input from Dr Judy Webb and others from the FOLV much of the content above is a synthesis of many inputs, All errors and misinterpretations are entirely mine.

Copyright

Headington Heritage’s content is protected under:

See here for details BY-NC-SA

Which means in summary you can copy, reuse for non commercial purposes with attribution.

The copyright for images, quotes and other material referenced from other sources belongs to the Copyright holder. Please contact me if you need any help about how to obtain permission where necessary.

References

4181 NEW ACCESS ROAD CHURCHILL HOSPITAL OXFORD, BGS, May 1973 (Site Investigation Report) (Ref: BGS)

Warren Crescent, Oxford, Discharge of Planning Condition, Condition 11 (SuDS), Report SDS, Ref: 4980-RP01 ISSUE 03 – September 2019 (Ref: SDS)

Warren Crescent, Oxford, Slope Stability Appraisal, Geotechnical, Report Ref: 36045 (Ref: GEO)

Warren Crescent, Oxford, Interpretative Report On Ground Investigation, Geotechnical, Report Ref: 35378 (Ref: GEO2)

Land East Of Warren Crescent, Land Quality Assessment, Oxford City Housing Limited, 7003712-012, July 2018 (Part 1&2) WSP (13_01555_CND-LAND_QUALITY_ASSESSMENT_-_PART_2_OF_2-2090445.pdf) (Ref: WSP)

Warren Crescent, Technical Note Ecology, SUDS and Groundwater Quality 2015, Project Ref: 27920,Rev: 01 Date: January 2016, Peter Brett and Associates (PBA)

Thames Water Utilities Limited Lye Valley Brook SSSI Catchment Investigation, Final Report RT/EWI/CH11/216/01.00 41518877 February 2012 (Ref: TWU)

Investigation of the possible hydrological effects on the Lye Valley Sites of Special Scientific Interest and the riparian zones of the Lye and Boundary Brooks as a result of development on Southfield Golf Course, A Pre-EIA Assessment, Oct 2007,Dr Curt Lamberth  (Pre-EIA)