Page 94 - Eden Meadow 35 houses application as of 12 October

3.0 Proposed Surface Water Drainage Strategy

3.1 Refer to Appendix B for a copy of the proposed Drainage Strategy Layout.
3.2 The design of the system will be prepared so as to prevent on and offsite flooding for any storm
event, up to and including a 1 in 100 year event, plus an allowance for the potential effects of climate
change (+ 40%). Similarly, by extension, the site will not flood for any events up to and including the
peak 1 in 30 year event. FEH data for the local catchment has been used in the design.
3.3 An uplift of 10% has also been added to account for the potential for Urban Creep.

3.4 The site lies outside of any Source Protection Zone (SPZ). However, given the proposal to discharge
ultimately to the ground, it is recognised that any potentially contaminated runoff should benefit
from a SuDS treatment stage.

3.5 Refer to the Water Quality Tool Proforma included as Appendix D.

3.6 Permeable paving is to be provided to most access roads, drives and parking spaces on the
development in order to function as treatment stage.
3.7 The SuDS Hierarchy has been duly considered and our explanation as to how we arrived at the
proposed strategy is noted under Appendix A.

3.8 The hierarchal assessment concludes that permeable paving, cellular soakaways and a small
infiltration basin, are the most appropriate SuDS measures to implement on this development.

3.9 Runoff from the site will be negligible given the proposal to discharge via infiltration.
3.10 Surface Water calculations are included under Appendix E.

3.11 Once full access is afforded, soakage testing will be carried out, with the results relayed to the project
engineer for assessment and detailed design purposes

4.0 Proposed Foul Water Drainage Strategy

4.1 Refer to Appendix B for a copy of the proposed Drainage Strategy Layout.

4.2 Foul water from the development will discharge, via gravity into the existing 150mm diameter FW
sewer which passes under the access road of Eden Meadow and onto the adopted sewer in the High
Street.

4.3 The sewer connection will be subject to formal consent from Southern Water, which we would not
expect to be unreasonably withheld.

5.0 Responsibility of Each Party for the implementation of the Drainage Measures

5.1 IDL are responsible for the design and detailing of the proposed drainage measures. Additionally,
approval will be sought from Building Control for compliance with Approved Document, Part H.

5.2 The developer and main contractor are responsible for installing the drainage system fully in
accordance with the approved design.

6.0 Timetable for Implementation

6.1 Once approved, the drainage measures will be installed as follows;