1. Stormwater Management June 2018 Andrea Phillips

2. Effects of development

3. Effects include MORE water (increased volume and velocity)
DIRTIER water (pollution and contaminants)
Hitting the same watercourse (if it’s lucky enough to not be piped).
Waterways have a large impact on our community – temperature, health and wellbeing.
What are we doing about it?

4. Erosion and lining

5. Drivers to manage sw National Policy Statement - Freshwater
Waikato Vision and Strategy
Regional Policy Statement
Healthy Rivers: Proposed Regional Plan Change 1
Comprehensive Consent
District Plan – ICMPs, WIA, WEM

6. Management ‘train’
Stormwater Management needs to be addressed at multiple locations:
At source stormwater reduction
On lot stormwater management
Sub-catchment management
Watercourse protection and enhancement

7. Document updates…best practice
Initial focus on new management devices to be in line with best practice:
At source and on lot reduction and mitigation:
WRC Stormwater Guidelines
Three Waters Management practice notes
Sub-catchment: Updates to Infrastructure Technical Specification.
Watercourse Protection: Programme of works within watercourses.

8. What decides a specific ‘on lot’ requirement?
WRC or HCC Consent
District Plan – general rule
District Plan – through an ICMP
District Plan – through WIA
HCC SW Bylaw (high risk sites)
Implemented through Building Consent.

9. ICMPs

11. Rotokauri sw treatment
Overview of Stormwater Treatment Train and Total Phosphorous Targets:

12. On lot: Three Waters Management Practice Notes
Created as a means of compliance for the HCC District Plan rule (water efficiency measure). May be specific from Resource Consent or ICMP

13. HCC02 – Rainwater reuse system (rain tank)

14. HCC02 – Rain tank below ground

15. HCC03 - Soakage

16. HCC04 – Bioretention (raingarden)

17. HCC04 – Bioretention (raingarden)

18. HCC06 - Detention

19. Next steps
Currently reviewing the on lot notes – incorporate learnings, understand the risk and liability, make it easy where we can (standard drawings).