CHAPTER 6: FINDINGS AND RECOMMENDATIONS

This chapter summarize the analysis and findings resulted from build-out scenario and need assessment pertaining to issues being raised in Waipahu and TOD and proposes recommendations based on the suitability analysis and best practice review.

In coping with 21st-century challenges such as increased energy cost, climate change, increased drought frequency, ecosystem health, and natural service deterioration, etc., Waipahu could apply integrated infrastructure planning, design, management using systems at various scales, based on context-specific sustainability objectives that emphasize low -impact design and best management practices (BMPs). Key takeaways from this study include:

1 Existing roadway capacity, parking facilities, stormwater facilities, and sewer pipelines in the Waipahu TOD area may not be sufficient to accommodate a full build-out future scenario in general.

2 Transportation Infrastructure

• A maximum build-out scenario for the state parcel based on the TOD zoning would significantly increase parking demands in the area and the traffic on adjacent roads (e.g. Mokuola street and Waipahu street). • To reduce the congestion and promote non-auto trips, pedestrian/bicycle/transit facilities along Paiwa St., Farrington Hwy, Awainui St., Mokuola St. Farrington Hwy. Awalau St., and Farrington Hwy should be prioritized for multimodal transportation facility improvement. Waipahu TOD would benefit from a reduction in future traffic and parking needs if public transit and walking friendly environment are prioritized. It is recommended to improve the an extensive network of pedestrian and bicycle facilities, add more bus connections with more frequent services, and implement strategies such as bus-only lanes where possible. • To reduce and accommodate the future parking needs, it is recommended to eliminate minimum parking requirements, implement district-level parking maximum, adopt regulations and incentives encouraging shared-parking, as well as regulations allow new parking structures to be adaptable to other uses to anticipate the emerging trends (e.g. autonomous shared vehicles, sea level rise). Compact mixed-use development as one objective of the TOD, is a catalyst for increasing parking efficiency and reducing the amount of parking needed in the area.

3 Stormwater management

• Development of state parcels and the TOD area would increase the overall stormwater runoff in the watershed by 12%, which could make the existing flooding problem worse. • The flooding problem is mostly caused by urban imperviousness in the whole watershed. Without upstream mitigation or additional stormwater facilities, it would need approximately 80% of the TOD development to be green/pervious surfaces in order to keep the future runoff at the current level. • Adopt Green Infrastructure when possible. Both the existing study and students’ community survey suggest the community’s strong interest in walkability, provision of green spaces for recreation, and the needs to mitigate flooding. Green infrastructure has the potential to address all these concerns. It is recommended that planners consider greenways, green corridors, green spaces, green roofs in

TOD areas if possible. Although green infrastructure could not solve the area’s flooding problem by itself, it has the potential to reduce the stormwater runoff and fulfill the community’s needs if implemented correctly. • Suitability analysis identifies areas such as Waipahu Depot, Farrington Hwy, and the state parcels as the most suitable places to implement green infrastructure in the watershed.

4 Wastewater Facilities

• Under the maximum build-out scenario, the state parcels could generate almost eight times the current wastewater flow. It is very likely that the 24’’ sewer main pipe needs to be upgraded in the future. • Given the potential significant increase in sewer discharge, besides the expensive upgrade of the pipelines in centralized wastewater system, it is recommended to examine the possibility of using decentralized wastewater treatment, which can reduce the overflow incidents from centralized system and have the technical flexibility to relocate and adapt to the changing climate if extreme weather becomes more frequent. Decentralized sewer that put emphasis on wastewater recycling system can also reduce the demand on public water infrastructure and water resources.

5 Finally, there is a need to examine the condition and needs for other utilities such as water and power when data become available.