nuuanu reservoir no. 1 dam information · to monitor and drain water from the reservoir. what level...
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Why am I receiving this notice?The Board of Water Supply (BWS) is providing this information bulletin on the Nuuanu Reservoir No. 1 Dam (OA-0154) as a community service.NO EVACUATIONS ARE BEING CALLED.Nuuanu Reservoir No. 1 Dam is located on the Ewa-side of Pali Highway above Pulelehua St. by Oahu Country Club. BWS operation of the Nuuanu Reservoir No. 1 DamBecause Nuuanu Reservoir No. 1 has no outlet works other than its emergency spillway, BWS regularly siphons water from the reservoir as part of its normal operations. This provides capacity in the reservoir for run-off. BWS continues to monitor and drain water from the reservoir.What level does the water need to reach to require mandatory evacuation?When the water level reaches a foot below the top of the dam, a mandatory evacuation notice will be issued. (The City Department of Emergency Management (DEM) and the State Dept. of Land and Natural Resources (DLNR) are currently reviewing evacuation triggers and will update their plans as necessary.) BWS is working with DEM to coordinate the evacuation plan, which includes public evacuation notification and designation of evacuation centers, only if needed.
If I need to be evacuated, how will BWS notify me?BWS will work with the City Department of Emergency Management (DEM) and other city agencies to provide notice to the affected residents. Should evacuation become mandatory, personnel from the Honolulu Police Department, Honolulu Fire Department, and DEM will notify the community.Do you have a list of streets in the evacuation zone so I can see if I live in that area? BWS worked with DEM to determine the extent of the evacuation zone. A map is on the other side of this sheet.
NUUANU RESERVOIR NO. 1 DAM INFORMATION
HAWAII DAM AND RESERVOIR SAFETY PROGRAM
BOARD OF WATER SUPPLY City & County of Honolulu 630 South Beretania Street Honolulu, HI 96843-0001
Inquiries & Information: (808) 748-5041 Water Emergencies: (808) 748-5000 Ext. 1 (24 hours) Office Hours: Monday – Friday, 7:45 a.m. to 4:30 p.m.Information: www.boardofwatersupply.com Email: [email protected]
BOARD OF WATER SUPPLY City & County of Honolulu 630 South Beretania Street Honolulu, HI 96843-0001
Inquiries & Information: (808) 748-5041 Water Emergencies: (808) 748-5000 Ext. 1 (24 hours) Office Hours: Monday – Friday, 7:45 a.m. to 4:30 p.m.Information: www.boardofwatersupply.com Email: [email protected]
NUUANU DAM NO 1• State Dam ID: OA-0154
• Year completed: 1899
• Purpose: flood control; water supply
• Dam type: Earthen
• Dam height: 34 feet
• Minimum crest width: 9 feet
• Dam length: 588 feet
• Storage: 21 million gallons
• Surface area: 10 acres
Top of Dam = 34’ Spillway = 31’
Toe of Dam = 0’
W.L. = 2.5’
Nuuanu Dam 1 (cross-
section)
Top of Dam = 34’ Spillway = 31’
Toe of Dam = 0’
W.L. = 2.5’
Nuuanu Dam 1 (cross-
section)
Top of Dam = 34’ Spillway = 31’
Toe of Dam = 0’
W.L. = 2.5’
Nuuanu Dam 1 (cross-
section)
Top of Dam = 34’ Spillway = 31’
Toe of Dam = 0’
W.L. = 2.5’
Nuuanu Dam 1 (cross-
section)
Crest to Toe = 34'
The Hawaii Dam and Reservoir Safety Program administered by the DLNR Engineering Division exists to protect the health, safety, and welfare of the citizens of the State by reducing the risk of failure ofthe dams or reservoirs
What are dams?A barrier constructed to hold back water resulting in a pool that can be used for a variety of purposes; agriculture, water supply, electricity generation, flood or sediment mitigation.
History of Dams in HawaiiSince the late 1800’s and early 1900’s many dams were built to support agriculture across the state.
Dam Safety Regulatory Program• 1980 US Army Corps of Engineers – conducts
Phase I inspection of High Hazard dams and develops the Hawaii regulated dam inventory
• 1987 Dam Safety Act (HRS 179D)• 1989 Hawaii Administrative Rules (HAR) 13-190• 2006 Kaloko Dam failure• 2007 Update “Hawaii Dam and Reservoir Safety
Act of 2007” (HRS 179D)• 2012 Update “Dams and Reservoirs”
(HAR 13-190.1)
Regulatory size• Greater than 25‐ft high and 16.3 million gallons
in volume, but nothing less than 6‐ft tall, or 4.9 million gallons in volume
October 2018 Statistics
• Regulates 131 dams and reservoirs statewide• Hawaii – 10• Maui – 56• Oahu – 13• Kauai – 52
Q&A1. Why should I care about dams?
a) Dams provide a great asset to the community by providing stored water for irrigation, drinking, energy generation and flood and sediment control. However, they come with risks if there were to be a dam failure. Not only the flooding of the community, but also the loss of the asset and its benefits.
2. What are risks associates with dams?a) Dam failures can be structural, mechanical or
hydraulic in nature.i. Structural – foundation defects causes the
failure of the embankmentii. Mechanical – malfunctioning gates or
valves can cause a dam failureiii. Hydraulic – overtopping due to inadequate
spillway design or as a result of other causes
3. Am I or could I be affected by a dam and what is the dam failure flood inundation area?a) Yes, potentially, if you live downstream of a
dam. Flood inundation areas and water flow down natural tributaries can be modeled. There is a potential for stream banks and drainage ways to be overtopped during a dam break due to an increase in flow.
b) You can find out if you live in a Dam Evacuation area by visiting http://gis.hawaiinfip.org/fhat/ or http://dlnreng.hawaii.gov/dam/ for more information about the program.
c) The evacuation area is a much larger area that may be affected by flooding. The evacuation area is designed by emergency managers to control the movement of people in and out of the potential hazard zone, and determined by the roadway network of a particular neighborhood.
4. Once I determine that my property is in a dam break inundation area, what’s next?a) Know where the dam is located, compared to
your location.b) Find out the downstream channel and
tributary stream or drainageway downstream of the dam.
c) Become familiar with the streets and major roadways that would be closed in the event of a potential dam break.
d) Become aware of how to move away from the potential flood wave. Depending on the downstream tributary, which direction to move, including vertical evacuation.
More Information1. Dams Public Inventory: dams.hawaii.gov2. Dam Evacuation Area: gis.hawaiinfip.org/fhat3. More Information: dlnreng.hawaii.gov/dam4. See if your address is in a Nuuanu evacuation
zone: boardofwatersupply.com/dams
These photos show the siphon system which helps to maintain the water level in the Nuuanu 1 reservoir.
In the event of a mandatory evacuation, where can I find an evacuation center?Locations of evacuation centers would be provided to community leaders and the media to share with the public. Stay tuned to local news media and social media channels for up-to-the-minute information.
Residents would need to bring everything they might need for at least 24 hours – food, water, bedding, toiletries, etc. The evacuation shelters would only provide a place to stay.Who should I contact for more information?For more information, please call the BWS Communications Office at 748-5041, or email [email protected].
Information presented in this document was the best available at the time of printing and is subject to change and update as new information becomes available.
NUUANU RESERVOIR NO. 1 DAM EMERGENCY EVACUATION PLAN
BOARD OF WATER SUPPLY City & County of Honolulu 630 South Beretania Street Honolulu, HI 96843-0001
Inquiries & Information: (808) 748-5041 Water Emergencies: (808) 748-5000 Ext. 1 (24 hours) Office Hours: Monday – Friday, 7:45 a.m. to 4:30 p.m.Information: www.boardofwatersupply.com Email: [email protected]
PALI
HW
Y
HUENE ST
W H1 FW
Y
N KING ST
LILIHA ST
N SCHOO
L ST
NUUANU AVE BOOTH RD
PAUOA RD
GULICK AVE
PACIFIC H
TS RD
KAM IV RD
HALA DR
DILLINGHAM BLVD
N KUAKINI ST
ALEWA DR
N JUDD ST
KOKEA ST
GIRLS RD
N NIMITZ HWY
ALII RD
TANTALUS DR
AUWAIOLIMU ST
AHIAHI ST
IWILEI RDPR
OS
PE
CT
ST
PUN
A S
T
HOUGHTAILING ST
AALA ST
HALONA ST
WYLLIE ST
NAIO
ST
OLOMEA ST
KALANI ST
NEHOA ST
HART ST
AUPUNI ST
RIVER ST
ROOKE AVE
COLBURN ST
MAKANANI DR
PUUNUI AVE
LUSITA
NA ST
PUIWA RD
KANEALII AVE
WAIA
KAMIL
O RD
PALI
HW
YBATES ST
PUOWAINA DR
HENRY STKAPALAMA AVE
PALAMA ST
ALANI ST
IAUKEA ST
MAUNAKEA ST
PUA LN
IOLANI AVE
AULII ST
ALAKAWA ST
LANAKILA AVE
JACK LN
KAPAHU ST
KULA ST
PARK ST
KOH
OU
ST
KEALIA DR
MOKAUEA ST
PALI RD
LAIMI R
D
BETHEL ST
WAOLANI AVE
IAO LN
MAUI ST
ROSE ST
KAUMUALII ST
KUNAWAI LN
FORT ST MALL
SMITH ST
BISHOP ST
S VINEYARD BLVD
KEKUANONI ST
SUM
NER
ST
BERNICE ST
KONIA ST
BISHOP CIR
KALI
HI ST
LINAPUNI ST
ALOKELE ST
MILLER ST
KAULULAAU ST
POHAKU ST
MAMAL
U ST
AHONUI ST
S SCHOOL ST
MAHALO ST
HAU ST
HAUIKI S
T
IHE ST
S BERETANIA ST
HAKA DR
KAILI ST
HILL
CRES
T ST
STAR RD
DOW ST
ALIK
A AV
E
MOOWAA ST
PUUHALE RD
DOWSETT AVE
RICHARD LN
MAG
ELLAN AVE
ALAKEA ST
AWA ST
ILIMA DR
PAINA ST
FORT ST
LAOLA PL
KUWILI ST
MEYERS ST
AHI PL
KILOHI ST
LAKI RD
AULD LN
KAUHANE ST
AUSTIN LN
AKINA ST
MA
UN
A PL
APIO LN
KOPKE ST
AHEKOLO ST
HAILI RD
ANALU ST
PIO PL
EKEKELA PL
KAUILA STKALAWAHIN
E PL
UHU ST
PELE ST
COELHO WAY
MAEMAE LN
PRINCESS DR
KAIA STHAW
AII ST
MARTIN ST
AKEPO LN
NU PL
KE ALA MANO S
T
WAILANI RD
MERCHANT ST
KUALONO ST
LONG LN
LAA LN
HIALOA ST
KAAAHI ST
KLEBAHN P
L
IHO
LENA
ST
LUN
A PL
KAENA LN
PACIFIC ST
KAMA LN
CLIO ST
HIKINA LN
ROBINSON LN
S KUAKINI ST
HIU ST
S JUDD ST
HUNA STBANYAN ST
OW
ENE LN
OLONA LN
SERENO ST
KEALOHA ST
LIKO LN
KEKAULIKE ST
EHEU ST
AMELIA ST
WALEA PL
PAHUKUI ST
FARR LN
HA
ALE
LEA
PL
KILAKILA DR
DAY PL
PALENA ST
EASY ST
WAIPA LN
KANANI PL
PONO KOPE
KUPU PL
AHIAHI PL
LADD LN
UHINI PL
KEKAU PL
NEHE LN
KOHOU ST
KALIHI S
T
AULD LN
DRAFT MAP
Nuuanu #1 DraftEvacuation Map
Street_Centerline
EvacZoneDRAFT
I
Prepared by:Honolulu Land Information System (HoLIS)Department of Planning and PermittingCity & County of HonoluluCopyright City & County of HonoluluAll Rights Reserved 2018Basemap Provided by ESRIPrepared Sept 2018 GISWR-21207Note: Data represented on this map is not intended to replace site survey.
PALI
HW
Y
HUENE ST
W H1 FW
Y
N KING ST
LILIHA ST
N SCHOO
L ST
NUUANU AVE BOOTH RD
PAUOA RD
GULICK AVE
PACIFIC H
TS RD
KAM IV RD
HALA DR
DILLINGHAM BLVD
N KUAKINI ST
ALEWA DR
N JUDD ST
KOKEA ST
GIRLS RD
N NIMITZ HWY
ALII RD
TANTALUS DR
AUWAIOLIMU ST
AHIAHI ST
IWILEI RD
PRO
SP
EC
T S
T
PUN
A S
T
HOUGHTAILING ST
AALA ST
HALONA ST
WYLLIE ST
NAIO
ST
OLOMEA ST
KALANI ST
NEHOA ST
HART ST
AUPUNI ST
RIVER ST
ROOKE AVE
COLBURN ST
MAKANANI DR
PUUNUI AVE
LUSITA
NA ST
PUIWA RD
KANEALII AVE
WAIA
KAMIL
O RD
PALI
HW
Y
BATES ST
PUOWAINA DR
HENRY STKAPALAMA AVE
PALAMA ST
ALANI ST
IAUKEA ST
MAUNAKEA ST
PUA LN
IOLANI AVE
AULII ST
ALAKAWA ST
LANAKILA AVE
JACK LN
KAPAHU ST
KULA ST
PARK ST
KOH
OU
ST
KEALIA DR
MOKAUEA ST
PALI RD
LAIMI R
D
BETHEL ST
WAOLANI AVE
IAO LN
MAUI ST
ROSE ST
KAUMUALII ST
KUNAWAI LN
FORT ST MALL
SMITH ST
BISHOP ST
S VINEYARD BLVD
KEKUANONI ST
SUM
NER
ST
BERNICE ST
KONIA ST
BISHOP CIR
KALI
HI ST
LINAPUNI ST
ALOKELE ST
MILLER ST
KAULULAAU ST
POHAKU ST
MAMAL
U ST
AHONUI ST
S SCHOOL ST
MAHALO ST
HAU ST
HAUIKI S
T
IHE ST
S BERETANIA ST
HAKA DR
KAILI ST
HILL
CRES
T ST
STAR RD
DOW ST
ALIK
A AV
E
MOOWAA ST
PUUHALE RD
DOWSETT AVE
RICHARD LN
MAG
ELLAN AVE
ALAKEA ST
AWA ST
ILIMA DR
PAINA ST
FORT ST
LAOLA PL
KUWILI ST
MEYERS ST
AHI PL
KILOHI ST
LAKI RD
AULD LN
KAUHANE ST
AUSTIN LN
AKINA ST
MA
UN
A PL
APIO LN
KOPKE ST
AHEKOLO ST
HAILI RD
ANALU ST
PIO PL
EKEKELA PL
KAUILA ST
KALAWAHINE PL
UHU ST
PELE ST
COELHO WAY
MAEMAE LN
PRINCESS DR
KAIA STHAW
AII ST
MARTIN ST
AKEPO LN
NU PL
KE ALA MANO S
T
WAILANI RD
MERCHANT ST
KUALONO ST
LONG LN
LAA LN
HIALOA ST
KAAAHI ST
KLEBAHN P
L
IHO
LENA
ST
LUN
A PL
KAENA LN
PACIFIC ST
KAMA LN
CLIO ST
HIKINA LN
ROBINSON LN
S KUAKINI ST
HIU ST
S JUDD ST
HUNA STBANYAN ST
OW
ENE LN
OLONA LN
SERENO ST
KEALOHA ST
LIKO LN
KEKAULIKE ST
EHEU ST
AMELIA ST
WALEA PL
PAHUKUI ST
FARR LN
HA
ALE
LEA
PL
KILAKILA DR
DAY PL
PALENA ST
EASY ST
WAIPA LN
KANANI PL
PONO KOPE
KUPU PL
AHIAHI PL
LADD LN
UHINI PL
KEKAU PL
NEHE LN
KOHOU ST
KALIHI S
T
AULD LN
DRAFT MAP
Nuuanu #1 DraftEvacuation Map
Street_Centerline
EvacZoneDRAFT
I
Prepared by:Honolulu Land Information System (HoLIS)Department of Planning and PermittingCity & County of HonoluluCopyright City & County of HonoluluAll Rights Reserved 2018Basemap Provided by ESRIPrepared Sept 2018 GISWR-21207Note: Data represented on this map is not intended to replace site survey.
Disclaimer: Information shown on this map is approximate and should be used as a guideline for emergency response. While the best available data has been utilized as inputs into a dam failure computer model, the final modeled product results should be interpreted as “best available estimates” of the evacuation areas. The computer model assumes that the dam fails from a defect in the embankment structure, while full at maximum capacity, under dry (no rain) conditions and no discharge through the spillway. Dam breaches during flooding or other hazard events could differ or be larger than the area identified.Should evacuations be initiated, listen to instructions from your local emergency management/civil defense agency, and directives from the police and fire departments. Based on the anticipated dam hazard or multiple hazards facing the community, this evacuation area may be altered by the local emergency management agency. The dam evacuation area is different from FEMA flood zone maps or the Tsunami Evacuation Maps (those can be viewed at: gis.hawaiinfip.org). Although the modeled dam failure area utilized to create the evacuation zone maps were conducted by PDC for the State DLNR, the displayed evacuation map is the product and property of the local County Emergency Management or Civil Defense Agency. Any usage or alteration of this map should be cleared with that respective county agency.For more information: contact local Emergency Management/Civil Defense Agency or visit: http://dlnreng.hawaii.gov/dam
If evacuation should become necessary, the City Department of Emergency Management (DEM) would notify residents in the flood zone of the potential need to evacuate their properties due to possible flooding from Nuuanu Reservoir No. 1.BWS constantly monitors and siphons excess water from the reservoir to maintain storm flow capacity. Occasionally, due to severe weather events, rainfall rates could exceed the standard siphoning capacity. In that case, additional pumps can be started to reduce the water level.In the event that water levels reach 1 ft. below the top of the dam, a mandatory evacuation notice will be issued to downstream areas. This evacuation could affect as many as 10,000 residents. (Please see the red-outlined area on the map.) Potential shelter locations would be identified.
DRAFT MAP