1. Russell Auwae Hannah Cooper Helder Da Costa Denise Duenas Abby Frazier James Frizzell Melissa Kahili

2. Introduction Hawai‘i’s success is due to fresh water available from Orographic rainfall Water is the most important natural resource Health Economics Land Use Sustenance

3. Objectives Where does the water go in the Mānoa basin? Ground Water Recharge Evapotranspiration for Hydrologic Cycle Human Impacts on Hydrologic Cycle Ecosystem Analysis Flood Analysis

4. Water Balance Model Text Description: Water Balance = Hydrometeorology + Soil Physics + Groundwater Hydrology Simple Water Balance Formula: Input = Output + Storage RF + Irr + CWI = RO + ET + GWR + SM

5. Water Balance Model Rainfall Potential Evapotranspiration Irrigation Run-off PIrrET Rchg RO SM

6. Input Parameters Available Water Capacity Root Depth (mm) Crop Factor Initial Soil Moisture (AW/AWC) Fraction of Area Paved (Amount of Land Cover Paved) Irrigated Area (Irrigated or Not Irrigated)

7. Outputs Actual Evapotranspiration Soil Moisture Content Groundwater Recharge

8. Evapotranspiration Average throughout Mānoa Valley *Total evapotranspiration: 171.9 mm

10. *Greatest amount of evapotranspiration occurs near Lyon Arboretum *Lowest values for found in the back of Mānoa Valley most likely due to low net radiation Evapotranspiration

11. How good is the water balance model when measuring Soil Moisture throughout Mānoa Valley?

12. *Total soil moisture: 22.8 mm

14. *Highest amounts of recharge occur near the Lyon Arboretum *Lowest amounts of recharge found in Mānoa urban/residential areas Recharge

16. RECHARGE Spatial Variation Grid 32: Total Rchg = 128.8mm Peak = 8.7mm in one hour Grid 58: Total Rchg = 21.9mm Peak = 2.07mm in one hour Grid 13: Total Rchg = 436.9mm Peak = 18.4mm in one hour Grid 47: Total Rchg = 272.6mm Peak = 13.15mm in one hour

17. *About half of the total recharge was produced in the last 22 days of the study *Total recharge produced: 258.8 mm

18. Water Balance in the Mānoa Basin Run-Off Storage

19. Water Balance Results Where the water went in the Mānoa Basin: Input: 708.9 mm / 10,997,895 m 3 Output: 709.6 mm / 11,008,754.82 m 3 NameSymbolActual AmountPercentage Input PrecipatationRF665.3 mm93.80% IrrigationIrr43.7 mm6.20% Total for Input708.9 mm100.00% Output Run-OffRO256.1 mm36.10% EvapotranspirationET171.9 mm24.20% RechargeGWR258.8 mm36.50% Soil Moisture ContentSM22.8 mm3.20% Total for Output709.6 mm100.00%

20. Summary Where the water went in the Mānoa Basin: Input: 708.9 mm / 10,997,895 m 3 Output: 709.6 mm / 11,008,754.82 m 3 RF + Irr = RO + ET + GWR + SM 93.8%6.2% 36.1% 24.2% 36.5%3.2%

21. Questions?