Data & Statistics

March 2023 Groundwater Levels Status Report

Please check back after the April 2023 BWS Board of Directors meeting.

February 2023 Groundwater Levels Status Report

Five aquifer index stations were in low groundwater condition for the production month of February 2023. Kaimuki, Pearl City, Kaluanui, and Waialua are in Caution Status. Punaluu is in Alert Status. The monthly production average for February 2023 was 121.49 million gallons per day.

The Board of Water Supply rainfall index for the month of February 2023 was 170 percent of normal, with a 5-month moving average of 94 percent. As of March 7, 2023, the Hawaii Drought Monitor shows zero drought conditions across Oahu. The National Weather Service is forecasting above-normal precipitation through April 2023.

Most monitoring wells exhibited relatively stable head levels for the month of February 2023, likely reflecting the lower overall groundwater production, recent relatively high rainfall, and the gradual recovery from prior months than of relatively low rainfall. Average monthly production for February 2023 was lower than in February 2022 and lower than the 5-year monthly average.

January 2023 Groundwater Levels Status Report

Five aquifer index stations were in low groundwater condition for the production month of January 2023. Kaimuki, Pearl City, Kaluanui, and Waialua are in Caution Status. Punaluu is in Alert Status. The monthly production average for January 2023, it was 131.20 million gallons per day.

The Board of Water Supply rainfall index for the month of January 2023, it was 105 percent of normal. The rainfall index 5-month moving average was 78 percent in January 2023. As of January 31, 2023, the Hawaii Drought Monitor shows zero drought to abnormally dry conditions moving roughly southwest across Oahu. The National Weather Service is forecasting above­normal precipitation through April 2023.

Most monitoring wells exhibited stable to slightly increasing head levels for the month of January 2023, likely reflecting the lower overall groundwater production combined with the relatively higher rainfall for the month of January. Average monthly production for January 2023 was higher than in January 2022 but similar to the 5-year monthly average. 

December 2022 Groundwater Levels Status Report

Five aquifer index stations were in low groundwater condition for the production month of December 2022. Kaimuki, Pearl City, Kaluanui, and Waialua are in Caution Status. Punaluu is in Alert Status. The monthly production average for December 2022 was 129.27 million gallons per day.

The Board of Water Supply rainfall index for the month of December 2022 was 64 percent of normal, with an identical 5-month moving average of 64 percent. As of January 3, 2023, the Hawaii Drought Monitor shows zero drought to abnormally dry conditions moving roughly south-southwest and north-northwest across Oahu. The National Weather Service is forecasting above-normal precipitation through March 2023.

Most monitoring wells exhibited stable to slightly decreasing head levels for the month of December, likely reflecting the lower overall groundwater production, combined with the relatively low rainfall for the month. Average monthly production for December 2022 was higher than in December 2021 but similar to the 5-year monthly average.

November 2022 Groundwater Levels Status Report

Five aquifer index stations were in low groundwater condition for the production month of November 2022. Kaimuki, Pearl City, Kaluanui, and Waialua are in Caution Status. Punaluu is in Alert Status. The monthly production average for November 2022 was 135.68 million gallons per day.

The Board of Water Supply rainfall index for the month of November 2022 was 51 percent of normal, with a 5-month moving average of 70 percent. As of November 29, 2022, the Hawaii Drought Monitor shows zero drought to moderate drought conditions moving roughly southwest and northwest across Oahu. The National Weather Service is forecasting above-normal precipitation through February 2023.

Most monitoring wells exhibited stable to increasing head levels for the month of November, likely reflecting the lower overall groundwater production, combined with the lower rainfall compared to the prior month. Average monthly production for November 2022 was lower than in November 2021 but similar to the 5-year monthly average.

October 2022 Groundwater Levels Status Report

Five aquifer index stations were in low groundwater condition for the production month of October 2022. Kaimuki, Pearl City, Kaluanui and Waialua are in Caution Status. Punaluu is in Alert Status. The monthly production average for October 2022 was 136.48 million gallons per day.

The Board of Water Supply rainfall index for the month of October 2022 was 78 percent of normal, with a 5-month moving average of 69 percent. As of November 8, 2022, the Hawaii Drought Monitor shows zero drought to moderate drought conditions moving roughly southwest and northwest across Oahu. The National Weather Service is forecasting above-normal precipitation from November 2022 through February 2023.

Most monitoring wells exhibited stable to slightly decreasing head levels for the month of October, likely reflecting the lower overall groundwater production, combined with the slightly lower rainfall compared to the prior month. Average monthly production for October 2022 was lower than in October 2021 but similar to the 5-year monthly average.

September 2022 Groundwater Levels Status Report

Six aquifer index stations were in low groundwater condition for the production month of September 2022. Beretania, Pearl City, Kaluanui and Waialua are in Caution Status. Kaimuki and Punaluu are in Alert Status. The monthly production average for September 2022 was 143.59 million gallons per day.

The Board of Water Supply rainfall index for the month of September 2022 was 94 percent of normal, with a 5-month moving average of 74 percent. As of October 4, 2022, the Hawaii Drought Monitor shows zero drought to severe drought conditions moving southwest across Oahu. The National Weather Service is forecasting enhanced probabilities for above-normal precipitation between roughly November 2022 through January 2023.

Most monitoring wells exhibited decreasing head levels for the month of September, likely due to the relatively higher overall groundwater production, and the significantly decreased rainfall from the prior month. Average monthly production for September 2022 was approximately the same as the previous year and the 5-year monthly average.

August 2022 Groundwater Levels Status Report

Four aquifer index stations were in low groundwater condition for the production month of August 2022. Kaluanui and Waialua are in Caution Status. Kaimuki and Punaluu are in Alert Status. The monthly production average for August 2022 was 150.92 million gallons per day.

The Board of Water Supply rainfall index for the month of August 2022 was 35 percent of normal, with a 5-month moving average of 69 percent. As of September 6, 2022, the Hawaii Drought Monitor shows abnormally dry to extreme drought conditions moving southwest across Oahu. The National Weather Service is forecasting enhanced probabilities for below-normal precipitation through at least November 2022.

Most monitoring wells exhibited relatively stable to decreasing head levels for the month, likely due to the relatively higher overall groundwater production, and the decreased rainfall compared to the prior month. Average monthly production for August 2022 was approximately the same as the previous year and the 5-year monthly average.

July 2022 Groundwater Levels Status Report

Four aquifer index stations were in low groundwater condition for the production month of July 2022. Waialua is in Caution Status. Kaimuki, Punaluu and Kaluanui are in Alert Status. The monthly production average for July 2022 was 143.76 million gallons per day.

The Board of Water Supply rainfall index for the month of July 2022 was 93 percent of normal, with a 5-month moving average of 72 percent. As of August 2, 2022, the  Hawaii Drought Monitor shows abnormally dry to severe drought conditions moving southwest across Oahu. The National Weather Service is forecasting enhanced probabilities for below-normal precipitation through at least November 2022, possibly as late as March 2023.

Most monitoring wells exhibited relatively stable head levels for the month, likely due to the relatively lower overall groundwater production, and the increased rainfall compared to the prior month. Average monthly Production for July 2022 was lower than the previous year and the 5-year monthly average. 

June 2022 Groundwater Levels Status Report

Four aquifer index stations were in low groundwater condition for the production month of June 2022. Kaluanui and Waialua are in Caution Status. Kaimuki and Punaluu are in Alert Status. The monthly production average for June 2022 was 143.22 million gallons per day.

The Board of Water Supply rainfall index for the month of June 2022 was 45 percent of normal, with a 5-month moving average of 63 percent. As of July 5, 2022, the Hawaii Drought Monitor shows abnormally dry to severe drought conditions moving westward across Oahu. The National Weather Service is forecasting enhanced probabilities for below-normal precipitation through November 2022.

Most monitoring wells exhibited relatively stable head levels for the month, likely due to the relatively lower overall groundwater production offsetting the low rainfall. Average monthly Production for June 2022 was lower than the previous year and the 5-year monthly average.

May 2022 Groundwater Levels Status Report

Three aquifer index stations were in low groundwater condition for the production month of May 2022. Waialua is in Caution Status. Kaimuki and Punaluu are in Alert Status. The monthly production average for May 2022 was 134.13 million gallons per day.

The Board of Water Supply (BWS) rainfall index for the month of May 2022 was 103 percent of normal, with a 5-month moving average of 76 percent. The National Weather Service (NWS) has noted that a mid-May storm event supplemented rainfall totals for portions of Oahu. This is reflected at some of the BWS rain gauges, primarily in metropolitan Honolulu.

As of June 7, 2022, the Hawaii Drought Monitor shows zero drought to severe drought conditions moving westward across Oahu. The NWS is forecasting enhanced probabilities for below-normal precipitation through November 2022.

Most monitoring wells exhibited relatively stable head levels for the month, likely due to the relatively lower overall groundwater production offsetting varying amounts of rainfall across the island. Average monthly Production for May 2022 was lower than the previous year and the 5-year monthly average. 

April 2022 Groundwater Levels Status Report

There were three aquifer index stations in low groundwater condition for the production month of April 2022. Waialua is in Caution Status. Kaimuki and Punaluu are in Alert Status. The monthly production average for April 2022 was 136.83 million gallons per day.

The Board of Water Supply rainfall index for the month of April 2022 was 71 percent of normal, with a 5-month moving average of 110 percent. As of May 3, 2022, the Hawaii Drought Monitor shows severe drought conditions in Leeward Oahu. The National Weather Service is forecasting enhanced probabilities for below-normal precipitation through October 2022.

Most monitoring wells exhibited varying degrees of decreasing head levels for the month, due to the relatively lower rainfall during February, March and April, combined with increasing groundwater production. Average monthly Production for April 2022 was higher than the previous year and the 5-year monthly average. 

March 2022 Groundwater Levels Status Report

There were three aquifer index stations in low groundwater condition for the production month of March 2022. Waialua is in Caution Status. Kaimuki and Punaluu are in Alert Status. The monthly production average for March 2022 was 135.29 million gallons per day.

The Board of Water Supply rainfall index for the month of March 2022 was 46 percent of normal, with a 5-month moving average of 104 percent. As of April 5, 2022, the Hawaii Drought Monitor shows abnormally dry to severe drought conditions moving westward across Oahu.

Most monitoring wells exhibited stable to decreasing head levels for the month, likely due to the relatively lower rainfall during March, combined with increasing groundwater production. Average monthly Production for March 2022 was higher than the previous year and the 5-year monthly average.

February 2022 Groundwater Levels Status Report

There were four aquifer index stations in low groundwater condition for the production month of February 2022. Kaimuki, Beretania, Punaluu, and Waialua are in Caution Status. The monthly production average for February 2022 was 132.52 million gallons per day.

The Board of Water Supply rainfall index for the month of February 2022 was 51 percent of normal, with a 5-month moving average of 109 percent. As of March 1, 2022, the Hawaii Drought Monitor shows moderate drought conditions across Oahu. The National Weather Service is forecasting enhanced probabilities for above-normal precipitation between March and June 2022.

Most monitoring wells exhibited slightly decreasing head levels for the month, likely due to the relatively lower rainfall during February. Average monthly Production for February 2022 was higher than the previous year and the 5-year monthly average.

January 2022 Groundwater Levels Status Report

There were three aquifer index stations in low groundwater condition for the production month of January 2022. Kaimuki, Punaluu, and Waialua are in Caution Status. The monthly production average for January 2022 was 123.75 million gallons per day.

The Board of Water Supply rainfall index for the month of January 2022 was 107 percent of normal, with a 5-month moving average of 120 percent. As of February 1, 2022, the Hawaii Drought Monitor shows abnormally dry conditions throughout the island of Oahu. The National Weather Service (NWS) is forecasting above-normal precipitation for February 2022. In addition, due to the present La Nina conditions, NWS is forecasting enhanced probabilities for above-normal precipitation through the winter months and into Spring 2022.

Most monitoring wells exhibited stable head levels for the month, likely due to decreased pumping during the winter season. Average monthly Production for January 2022 was lower than the previous year and the 5-year monthly average. 

December 2021 Groundwater Levels Status Report

There were two aquifer index stations in low groundwater condition for the production month of December 2021. Kaimuki and Punaluu are in Caution Status. The monthly production average for December 2021 was 124.31 million gallons per day. 

The Board of Water Supply rainfall index for the month of December 2021 was 276  percent of normal, with a 5-month moving average of 118 percent. As of January 4, 2022, the Hawaii Drought Monitor shows no dry conditions on the island of Oahu. The National Weather Service (NWS) is forecasting above-normal precipitation for January 2022. In addition, due to the present La Nina conditions, NWS is forecasting enhanced probabilities for above normal precipitation through the winter months and into Spring 2022.

Most monitoring wells exhibited increasing head levels for the month, due to decreased pumping during the winter season and the recent heavy rainfall. Average monthly Production for December 2021 was lower than the previous year and the 5-year monthly average.  

November 2021 Groundwater Levels Status Report

There were two aquifer index stations in low groundwater condition for the production month of November 2021. Kaimuki is in Caution Status. Punaluu is in Alert Status. The monthly production average for November 2021 was 140.01 million gallons per day.

The Board of Water Supply rainfall index for the month of November 2021 was 39 percent of normal, with a 5-month moving average of 77 percent. As of November 30, 2021, the Hawaii Drought Monitor showed a gradation from abnormally dry conditions on the windward side of Oahu to moderate drought conditions on the leeward side of the Koolau Mountains and Honolulu, and severe drought conditions for the rest of the island. The National Weather Service (NWS) is forecasting above-normal precipitation for December 2021. In addition, due to the present La Nina conditions, NWS is forecasting enhanced probabilities for above normal precipitation through the winter months and into Spring 2022.

Most monitoring wells exhibited stable to slightly decreasing head levels for the month, likely due to increased pumping during the fall dry season. Average monthly Production for November 2021 was higher than the previous year and the 5-year monthly average.

October 2021 Groundwater Levels Status Report

There were four aquifer index stations in low groundwater condition for the production month of October 2021. Waialua and Pearl City are in Caution Status. Kaimuki and Punaluu are in Alert Status. The monthly production average for October 2021 was 143.82 million gallons per day.

The Board of Water Supply rainfall index for the month of October 2021 was 74 percent of normal, with a 5-month moving average of 79 percent. As of November 2, 2021, the Hawaii Drought Monitor showed a gradation from abnormally dry to moderate drought conditions on the leeward side of Oahu from Honolulu to Ka'ena Point, and severe drought conditions on the leeward coast from Ewa Beach to Makaha. The National Weather Service (NWS) is forecasting below-normal precipitation for November 2021. However, according to NWS, La Nina conditions are now present across the Pacific Ocean. The transition from drier conditions in autumn to wetter conditions in winter across the Hawaiian Islands is consistent with the impacts of La Nina conditions. Therefore, NWS is forecasting above normal precipitation from December 2021 to Spring 2022.

Most monitoring wells exhibited stable to slightly decreasing head levels for the month, likely due to increased pumping during the summer and fall dry season. Average monthly Production for October 2021 was higher than the previous year and the 5-year monthly average.

September 2021 Groundwater Levels Status Report

There are four aquifer index stations in low groundwater condition for the production month of September 2021. Pearl City and Waialua are in Caution Status. Kaimuki and Punaluu are in Alert Status. The monthly production average for September 2021 was 144.01 million gallons per day.

The Board of Water Supply rainfall index for the month of September 2021 was 103 percent of normal, with a 5-month moving average of 74 percent. As of October 5, 2021, the Hawaii Drought Monitor showed a gradation from abnormally dry to moderate drought conditions on the leeward side of Oahu from Honolulu to Makaha, and severe drought conditions on the leeward coast from Pearl Harbor to Kapolei. The National Weather Service is forecasting above-normal precipitation as of November, due to current ENSO-neutral conditions likely transitioning to La Nina conditions by winter.

Most monitoring wells exhibited stable to slightly decreasing head levels for the month, likely due to increased pumping during the summer dry season. Average monthly production for September 2021 was lower than the previous year, and slightly lower than the 5-year monthly average.

August 2021 Groundwater Levels Status Report

There were three aquifer index stations in low groundwater condition for the production month of August 2021. Waialua is in Caution Status. Kaimuki and Punaluu are in Alert Status. The monthly production average for August 2021 was 150.48 million gallons per day.

The Board of Water Supply rainfall index for the month of August 2021 was 98 percent of normal, with a 5-month moving average of 66 percent. As of August 31, 2021, the Hawaii Drought Monitor showed a gradation from abnormally dry conditions along the leeward slopes of the Ko'olau Range to severe drought conditions along the leeward coast from Pearl Harbor to Makaha. The National Weather Service is forecasting below-normal precipitation through November, due to current ENSO-neutral conditions, with increasing probability of La Nina conditions and above-normal rainfall by winter.

Most monitoring wells exhibited stable to slightly decreasing head levels for the month, likely due to increased pumping during the summer dry season combined with relatively higher rainfall compared to recent months. Average monthly Production for August 2021 was slightly higher than the previous year and slightly lower than the 5-year monthly average.

July 2021 Groundwater Levels Status Report

There were three aquifer index stations in low groundwater condition for the production month of July 2021. Kaimuki and Waialua are in Caution Status. Punaluu is in Alert Status. The monthly production average for July 2021 was 150.86 million gallons per day.

The Board of Water Supply rainfall index for the month of July 2021 was 69 percent of normal, with a 5-month moving average of 88 percent. As of August 3, 2021, the Hawaii Drought Monitor showed abnormally dry conditions on the island of Oahu; with moderate drought conditions on the leeward side of the island from Honolulu to Haleiwa; and severe drought conditions along the leeward coast from Pearl Harbor to Makaha. The National Weather Service (NWS) is forecasting below normal precipitation for August 2021. Below-normal precipitation is likely through November, due to current ENSO-neutral conditions, with increasing probability of La Nina conditions by winter.

Most monitoring wells exhibited decreased head levels for the month, likely due to increased pumping during the summer dry season. Average monthly Production for July 2021 was higher compared to the previous year and the 5-year monthly average.  

June 2021 Groundwater Levels Status Report

There were three aquifer index stations in low groundwater condition for the production month of June 2021. Kaimuki and Waialua are in Caution Status. Punaluu is in Alert Status. The monthly production average for June 2021 was 149.97 million gallons per day.

The Board of Water Supply rainfall index for the month of June 2021 was 51 percent of normal, with a 5-month moving average of 97 percent. As of July 6, 2021, the Hawaii Drought Monitor showed abnormally dry conditions on most of the island of Oahu, except for the Koolau Area on the windward side; and moderate drought conditions along the leeward coast from Honolulu to Makaha. The National Weather Service (NWS) is forecasting below normal precipitation for the summer months. NWS (through a presentation to the Oahu Drought Committee) is also predicting a late start to the winter wet season which may bring above average rainfall as current ENSO neutral conditions possibly transition to increasing chances of La Nina conditions by winter.

Most monitoring wells exhibited decreased head levels for the month, likely due to increased pumping during the summer dry season. Average monthly Production for June 2021 was slightly higher compared to the previous year and the 5-year monthly average. In order to help mitigate the declining head levels during the summer months we use social media outlets (Facebook, Twitter, Instagram), LIVE TV interviews, and our website to educate the public about water conservation. We also have the Water Sensible Program which offers rebates on clothes washers, rain barrels and weather-based irrigation controllers, and the Water Smart Program that gives customers access to their water use trends with conservation tips to reduce their water use.

May 2021 Groundwater Levels Status Report

There were two aquifer index stations in low groundwater condition for the production month of May 2021. Punaluu and Waialua are in Caution Status. The monthly production average for May 2021 was 140.91 million gallons per day.

The Board of Water Supply rainfall index for the month of May 2021 was 51 percent of normal, with a 5-month moving average of 125 percent. As of June1, 2021, the Hawaii Drought Monitor showed abnormally dry conditions on most of the island of Oahu, except for portions of the windward side; and moderate drought conditions from Pearl Harbor to Kapolei. The National Weather Service is forecasting below normal precipitation for the summer months.

Most monitoring wells exhibited decreased head levels for the month, likely due to increased pumping during the summer dry season. Average monthly Production for May 2021 was slightly higher compared to the previous year and the 5-year monthly average.

April 2021 Groundwater Levels Status Report

There were two aquifer index stations in low groundwater condition for the production month of April 2021. Punaluu and Waialua are in Caution Status. The monthly production average for April 2021 was 132.80 million gallons per day.

The Board of Water Supply rainfall index for the month of April 2021 was 63 percent of normal, with a 5-month moving average of 127 percent. As of May 4, 2021, the Hawaii Drought Monitor showed abnormally dry conditions for the island of Oahu. The National Weather Service is forecasting below normal precipitation for the coming summer months.

Most monitoring wells exhibited decreased head levels for the month, likely due to increased pumping because of decreased rainfall during the month. Average monthly Production for April 2021 was higher compared to the previous year and the 5-year monthly average.

March 2021 Groundwater Levels Status Report

There were two aquifer index stations in low groundwater condition for the production month of March 2021. Punaluu and Waialua are in Caution Status. The monthly production average for March 2021 was 121.01 milion gallons per day.

The Board of Water Supply rainfall index for the month of March 2021 was 208 percent of normal, with a 5-month moving average of 130 percent. As of April 6, 2021, the Hawaii Drought Monitor showed no dry conditions for the island of Oahu. The National Weather Service is forecasting La Nina conditions continuing through the spring months, with potential above-normal rainfall through June 2021.

Most monitoring wells exhibited increased head levels for the month due to decreased pumping and increased rainfall during the emonth. Average monthly Production for March 2021 was lower compared to the previous year and the 5-year monthly average.

February 2021 Groundwater Levels Status Report

There were two aquifers index stations in low groundwater condition for the production month of February 2021. Waialua is Caution Status, and Punaluu is in Alert status. The monthly production average for February 2021 was 124.77 million gallons per day, which is below the 5-year mothing average.

The Board of Water Supply rainfall index for the month of February 2021 was 110 percent of normal, with a 5-month moving average of 98 percent. As of March 2, 2021, the Hawaii Drought Monitor shows abnormally dry conditions along the leeward coast of Oahu from Ewa Beach to Makaha. The National Weather Service is forecasting La Nina conditions continuing through the spring months, with potential above-normal rainfall through June 2021.

Most monitoring wells (except for January 2021) have continued to exhibit decreasing trends during the Winter season, possibly due to below average rainfall from April to December 2020. Production during the same time period has usually been consistent with previous years. However, average monthly Production for February 2021 was below the previous year and the 5-year monthly average.

January 2021 Groundwater Levels Status Report

There was one aquifer index station in low groundwater condition for the produciton month of January 2021. Punaluu is in Caution status. The monthly production average for January 2021 was 127.56 million gallons per day, which is below the 5-year monthly average.

The Board of Water Supply rainfall index for the month of January 2021 was 194 percent of normal, with a 5-month moving average of 83 percent. As of February 2, 2021, the Hawaii Drought Monitor shows abnormally dray conditions through Central Oahu from Pearl Harbor to Ka'ena Point; and moderate drought conditions on the leeward coast from Ewa Beach to Makaha. The National Weather Service is forecasting La Nina conditions continuing through the spring months, with potential above-normal rainfall through July 2021.

Most monitoring wells exhibit stable to slightly increasing trends, likely reflecting increased rainfall during the past month along with slightly reduced production.

December 2020 Groundwater Levels Status Report

There was one aquifer index station in low groundwater condition for the production month of December 2020. Punaluu is in Caution status. The monthly production average for December 2020 was 130.82 million gallons per day, which is slightly above the 5-year monthly average. Most monitoring stations are exhibiting slightly declining water level trends.

The Board of Water Supply (BWS) rainfall index for the month of December 2020 was 58 percent of normal, with a 5-month moving average of 53 percent. As of January 5, 2021, the Hawaii Drought Monitor shows abnormally dry conditions in the coastal areas of Waimanalo and Honolulu through Central Oahu and portions of the North Shore; and moderate drought conditions on the leeward coast from Ewa Beach to Makaha. The National Weather Service is forecasting La Nina conditions continuing through the spring months, with potential above-normal rainfall through June 2021.

As reported at the October 26th Board Meeting, BWS initiated a voluntary conservation notice of 10 percent for Windward and East Honolulu, due to declining water levels coupled with unusually hot weather and low rainfall conditions for the previous 7 months. We recognize that many customers continue to use water wisely and reduce water waste; we commend them for their efforts. Due to only one station currently being in caution status (Punaluu), we intend to lift the voluntary conservation notice at the end of January. 

November 2020 Groundwater Levels Status Report

As reported at the October 26th Board Meeting, BWS initiated a voluntary conservation notice of 10% for Windward and East Honolulu due to declining water levels coupled with unusually hot weather and low rainfall conditions for the previous 7 months.

Presently, there are two aquifer index stations in low groundwater condition. Kaimuki is in Alert condition, while Punaluu is in Caution condition. The monthly production average for November 2020 was 130.14 million gallons per day, which is slightly less than the 5-year monthly average. Most monitoring stations are exhibiting fairly stable water level trends.

The Board of Water Supply rainfall index for the month of November was 79 percent of normal, with a 5-month moving average of 60 percent. As of December 1, 2020, the Hawaii Drought Monitor shows abnormally dry conditions across roughly the southwestern half of Oahu, with moderate drought conditions on the Ewa Plain and the eastern end of Oahu. The National Weather Service is forecasting La Nina conditions continuing through the winter months, with potential above-normal rainfall through June 2021.

We recognize that many customers continue to use water wisely and reduce water waste; we commend them for their efforts. We are asking all our customers to lower their water use where possible through the end of the year.

October 2020 Groundwater Levels Status Report

As reported at the October 26th Board Meeting, the Board of Water Supply (BWS) initiated a voluntary conservation notice of 10 percent for Windward and East Honolulu, due to declining water levels coupled with unusually hot weather and low rainfall conditions for the previous 7 months.

Presently, there are two aquifer index stations in low groundwater condition. Punaluu and Kaimuki are in Alert low groundwater condition. The monthly production average for October 2020 was 138.72 million gallons per day, which is very similar to the 5-year monthly average. Most monitoring stations are exhibiting stabilizing water level trends.

The BWS rainfall index for the month of October was 48 percent of normal, with a 5-month moving average of 57 percent. As of November 3, 2020, the Hawaii Drought Monitor shows moderate drought conditions across Oahu, with severe drought conditions on the leeward coast stretching from Ewa Beach to Makaha. The National Weather Service is forecasting La Nina conditions, with potential above-normal rainfall through April.

We recognize that many customers continue to use water wisely and reduce water waste; we commend them for their efforts. We are asking all our customers to lower their water use where possible through the end of the year. 

September 2020 Groundwater Levels Status Report

BWS has initiated a voluntary conservation notice of 10% for Windward and East Honolulu due to declining water levels coupled with unusually hot weather and low rainfall conditions for the last 7 months, April through October.

There were three aquifer index stations in low groundwater condition. Punaluu and Kaimuki are in Alert, and Waihee Tunnel is in Critical low groundwater condition. The monthly production average for September 2020 was 153.10 million gallons per day, which is about 8 mgd above the 5-year monthly average. Most monitoring stations are exhibiting decreasing water level trends.

The Board of Water Supply rainfall index for the month of September 2020 was 38 percent of normal, with a 5-month moving average of 58 percent. As of October 6, 2020, the Hawaii Drought Monitor shows abnormally dry conditions for the windward side of Oahu, moderate drought conditions on the leeward side of Oahu, and severe drought conditions on the leeward coast stretching from Ewa Beach to Makaha. The National Weather Service is predicting below average rainfall for October 2020 and has updated their wet season forecast confirming previous forecasts that a La Nina condition exists with expectations for above normal rainfall this winter.

The BWS Communications Office, with the help of the Water Conservation Branch, have sent letters requesting voluntary conservation to state and city agencies, military installations, large water users, and the neighborhood boards. Recommendations include:

• Limit lawn and landscape irrigation to twice a week, before 9 a.m. or after 5 p.m. when evaporation is lower;
• Postponing installation of new landscaping (which require constant irrigation);
• Postponing car washes and refilling of swimming pools;
• Checking and fixing dripping faucets and running toilets;
• Check for and repair property leaks, especially on irrigation systems.

In addition, a news release was sent to all TV, radio, and social media outlets. The release resulted in several interviews and a newspaper article discussing the drought and conservation.

We recognize that many customers are already doing their best to use water wisely and reduce water waste; we commend them for their efforts. We are asking all our customers to lower their water use where possible through the end of the year.

August 2020 Groundwater Levels Status Report

There were three aquifer index stations within low groundwater status for the production month of August 2020. Punaluu and Waihee Tunnel are in Caution status. Kaimuki is in Alert status. The monthly production average for August 2020 was 148.48 million gallons per day (MGD). The Board of Water Supply rainfall index for the month of August 2020 was 41 percent of normal, with a 5-month moving average of 57 percent. As of September 8, 2020, the Hawaii Drought Monitor shows abnormally dry conditions for Oahu, with moderate drought conditions on the Leeward side of Oahu stretching from Pearl Harbor to Haleiwa to the Leeward coast. The National Weather Service is predicting below average rainfall for September and October 2020. Most monitoring wells are exhibiting decreasing trends, likely due to increased pumping during the summer dry season. Production for August 2020 was slightly lower compared to the previous year. 

July 2020 Groundwater Levels Status Report

There were two aquifer index wells within low groundwater status for the production month of July 2020. Kaimuki and Punaluu are in Caution status. The monthly production average for July 2020 was 145.20 million gallons per day (MGD).

The Board of Water Supply rainfall index for the month of July 2020 was 92 percent of normal, with a 5-month moving average of 77 percent. As of August 4, 2020, the Hawaii Drought Monitor shows abnormally dry conditions for most of leeward Oahu from Honolulu to Makaha to Haleiwa, with moderate drought conditions in the Ewa, Waipahu, and Kapolei areas. The National Weather Service is predicting below average rainfall from August 2020 through the fall months.

Most monitoring wells are exhibiting static to slightly decreasing trends, likely due to increased pumping during the summer dry season. Production for July 2020 was slightly higher compared to the previous year.

June 2020 Groundwater Levels Status Report

There were two aquifer index wells within low groundwater status for the production month of June 2020. Punaluu is under a Caution status. Kaimuki is in Alert Status. The monthly production average for June 2020 was 148.13 million gallons per day (MGD).

The Board of Water Supply rainfall index for the month of June 2020 was 68 percent of normal, with a 5-month move average of 72 percent. As of July 7, 2020, the Hawaii Drought Monitor shows abnormally dry conditions for all of Oahu, with moderate drought conditions for leward Oahu. The National Weather Service describes Hawaii as being in a dry season and is predicting below-normal precipitation through September 2020. 

Most monitoring wells are exhibiting decreasing trends, likely due to increased pumping during the summer dry season.

May 2020 Groundwater Levels Status Report

There were two aquifer index wells within low groundwater status for the production month of May 2020. Punaluu and Waialua are under a Caution status. The monthly production average for May 2020 was 140.04 million gallons per day.

The Board of Water Supply rainfall index for the month of May 2020 was 49 percent of normal, with a 5-month move average of 96 percent. As of June 2, 2020, the Hawaii Drought Monitor shows abnormally dry conditions for most of Oahu, with moderate drought conditions along the coastal regions from Ewa Beach to Makaha. The National Weather Service describes Hawaii as entering a dry season and is predicting below-normal precipitation through August 2020. 

Most monitoring wells are exhibiting decreasing trends, likely due to increased pumping during the summer dry season. Production for May 2020 was slightly higher compared to the previous year.

April 2020 Groundwater Levels Status Report

There were two aquifer index wells within low groundwater status for the production month of April 2020. Punaluu and Waialua are under a Caution status. The monthly production average for April 2020 was 126.14 million gallons per day (MGD).

The Board of Water Supply rainfall index for the month of April 2020 was 35 percent of normal, with a 5-month moving average of 110 percent. As of May 5, 2020, the Hawaii Drought Monitor shows no dry conditions for the island of Oahu. The National Weather Service describes Hawaii as entering a dry season and is predicting below-normal precipitation through July 2020.

Most monitoring wells are exhibiting increasing trends, likely due to decreased pumping because of the COVID-19 pandemic. Production for April 2020 was 8 MGD lower compared to the 5-year monthly average of 134 MGD for April, a reduction of about 6 percent.

March 2020 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of March 2020. The monthly production average for March 2020 was 124.22 million gallons per day.

The Board of Water Supply rainfall index for the month of March 2020 was 139 percent of normal, with a 5-month moving average of 111 percent. As of April 7, 2020, the Hawaii Drought Monitor shows no dry conditions for the island of Oahu.

Most monitoring wells are exhibiting increasing trends, likely due to decreased pumping because of increased rainfall and decreased water usage during the last few weeks of th COVID-19 pandemic. Production for March 2020 was 8 MGD lower compared to the 5-month moving average of 132 MGD for March, a reduction of about 6 percent.

February 2020 Groundwater Levels Status Report

There are two aquifer index well within low groundwater status for the production month of February 2020. Punaluu and Waialua are under a Caution status. A revised geodetic benchmark elevation survey was completed in January 2020 which decreased head level measureents in Punaluu and Waialua. The benchmark decrease in Waialue was large enough to place Waialua in Caution Status with no significant change in pumping levels in adjacent wells. The decrease in head level measurements in Punaluu is also attributable to lower than normal rainfall in Windward Oahu. The monthly production average for February 2020 was 127.82 million gallons per day.

The Board of Water Supply rainfall index for the month of February 2020 was 68 percent of normal, with a 5-month moving average of 103 percent. As of March 3, 2020, the Hawaii Drought Monitor shows no dry conditions for the island of Oahu. The National Weather Service is predicting above-normal precipitation for March 2020, and forecasts above-normal rainfall through May 2020.

January 2020 Groundwater Levels Status Report

There is one aquifer index well within low groundwater status for the production month of January 2020. Punaluu is under a Caution status. The monthly production average for January 2020 was 126.92 million gallons per day.

The Board of Water Supply rainfall index for the month of January 2020 was 117 percent of normal, with a 5-month moving average of 92 percent. As of February 4, 2020, the Hawaii Drought Monitor shows no dry conditions for the island of Oahu. The National Weather Service is predicting above normal precipitation for February, and forecasts above-normal rainfall through June 2020 due to persistent elevated sea surface temperatures predicted by most climate change models.

Most monitoring wells continue to exhibit stable trends. Production for January 2020 was down compared to previous years.

December 2019 Groundwater Levels Status Report

There is one aquifer index well within low groundwater status for the production month of December 2019. Punaluu is under a Caution status. The monthly production average fo December 2019 was 131.24 million gallons per day. 

As of January 7, 2020, the Hawaii Drought Monitor shows abnormally dry conditions along the leeward coast of Oahu from Ewa Beach to Kaena Point. The National Weather Service forecasts above-normal rainfall through June 2020, due to persistent elevated sea surface temperatures prredicted by most climate models.

Most monitoring wells exhibit stable trends.

November 2019 Groundwater Levels Status Report

As of December 6, 2019, available data indicate that aquifer indent well Kaimuki has come out of Caution status, while Punaluu remains in Caution status. The monthly production average for November 2019 was 134.80 million gallons per day.

As of December 43, 2019, the Hawaii Drought Monitor shows abnormally dry conditions along portions of the southern coast of Oahu. The National Weather Service forecasts above-normal rainfall thorugh May 2020, due to persistent elevated sea surface temperatures predicted by most climate models.

October 2019 Groundwater Levels Status Report

There are two aquifer index wells within low groundwater status for the production month of October 2019. Kaimuki and Punaluu are under a Caution status. The monthly production average for October 2019 was 136.01 million gallons per day.

The Board of Water Supply rainfall index for the month of October 2019 was 99 percent of normal; with a 5-month moving average of 107 percent. As of November 5, 2019, the Hawaii Drought Monitor shows abnormally dry conditions along portions of the southern coast of Oahu. The National Weather Service forecasts above-normal rainfall through May 2020, due to persistent elevated sea surface temperatures predicted by most climate models. 

Most monitoring wells exhibit stable to slightly decreasing trends, likely reflecting increased rainfall during the past month along with slightly reduced production.

September 2019 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of September 2019. The monthly production average for September 2019 was 148.30 million gallons per day.

The Board of Water Supply rainfall index for the month of September 2019 was 147 percent of normal; with a 5-month moving average of 101 percent. As of October 8, 2019, the Hawaii Drought Monitor shows abnormally dry to moderate drought conditions along the southern coast of Oahu.
 

August 2019 Groundwater Levels Status Report

There is one aquifer index well within low groundwater status for the production month of August 2019. Kaimuki is under a Caution status. The monthly production average for August 2019 was 152.39 million gallons per day.

The Board of Water Supply rainfall index for the month of August 2019 was 55 percent of normal; with a 5-month moving average of 84 percent. As of September 3 6, 2019, the Hawaii Drought Monitor shows abnormally dry to moderate conditions for all of Oahu.

Most monitoring wells continue to show decreasing trends, reflecting increased pumping through the summer months.

July 2019 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of July 2019. The monthly production average for July 2019 was 144.51 million gallons per day.

The Board of Water Supply rainfall index for the month of July 2019 was 58 percent of normal; with a 5-month moving average of 77 percent. As of August 6, 2019, the Hawaii Drought Monitor shows abnormally dry conditions for all of Oahu.

Most monitoring wells are showing decreasing trends, resulting from increased pumping through the summer months.

June 2019 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of June 2019. The monthly production average for June 2019 was 144.43 million gallons per day.

The Board of Water Supply rainfall index for the month of June 2019 was 174 percent of normal; with a 5-month moving average of 97 percent. As of July 2, 2019, the Hawaii Drought Monitor shows abnormally dry conditions for southern Oahu from Honolulu to Makaha, with moderate drought conditions on the leeward side of the island, Ewa Beach to Waianae. The wildfire season has started early this year.

The Oahu Drought Committee met on June 25, 2019. The National Weather Service is currently observing weak El Nino conditions around the Hawaiian Islands. A weak El Nino is likely to continue through the summer and possibly through fall and winter. Similar to last month's reporting, continuation of El Nino conditions through the summer normally correlates to decreased precipitation on Oahu. However, the Central Pacific Hurricane Center has predicted above-normal tropical cyclone activity during this hurricane season, thereby increasing probabilities for above normal rainfall during the summer months. If the El Nino weakens to neutral, more rainfall is possible during the 2019-2020 wet season. lf El Nino continues, drier wet season is more likely.

Most monitoring wells are showing slightly decreasing to static trends, resulting from increased pumping through the summer months.

May 2019 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of May 2019. The monthly production average for May 2019 was 138.71 million gallons per day. The Board of Water Supply rainfall index for the month of May 2019 was 69 percent of normal; with a 5-month moving average of 72 percent. As of June 4, 2019, the Hawaii Drought Monitor shows abnormally dry conditions for all of Oahu, with moderate drought conditions on the leeward side of the island, and severe drought conditions on the leeward coast from Nanakuli to Makaha. The National Weather Service (NWS) is predicting the continuation of El Nino conditions through the summer which normally can correlate to decreased precipitation on Oahu. However, the Central Pacific Hurricane Center is predicting 70 percent chance of above-normal tropical cyclone activity during the hurricane season. The NWS said that Hawaiian Islands could be threatened by 5 to 8 storms from June through November; increasing probabilities for above normal rainfall during the summer months. Most monitoring wells are showing decreasing trends, resulting from below average rainfall and increased pumping during the summer months.

April 2019 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of April 2019. The monthly production average for April 2019 was 142 million gallons per day.

The Board of Water Supply rainfall index for the month of April 2019 was 62 percent of normal; with a 5-month moving average of 76 percent. As of May 7, 2019, the Hawaii Drought Monitor shows abnormally dry conditions for all of Oahu, with moderate drought conditions on the leeward side of the island from Makaha, to Haleiwa, to Diamond Head. The National Weather Service is forecasting below normal rainfall for May 2019.

Most monitoring wells are showing slightly decreasing trends, likely resulting from increased pumping because of warmer weather and decreased rainfall during the last few weeks.

March 2019 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of March 2019. The monthly production average for March 2019 was 132.51 million gallons per day.

The Board of Water Supply rainfall index for the month of March 2019 was 23 percent of normal; with a 5-month moving average of 79 percent. As of April 2, 2019, the Hawaii Drought Monitor shows abnormally dry for the leeward side of the island. The National Weather Service is forecasting below normal rainfall for April 2019.

Most monitoring wells are showing slightly decreasing trends, likely resulting from increased pumping because of the decreased rainfall during the last few weeks.

February 2019 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of February 2019. The monthly production average for February 2019 was 123.94 million gallons per day.

The Board of Water Supply rainfall index for the month of February 2019 was 157 percent of normal; with a 5-month moving average of 108 percent. As of March 5, 2019, the Hawaii Drought Monitor shows abnormally dry for the leeward side of Oahu, from Ewa to Kapolei. The National Weather Service is forecasting below normal rainfall for March 2019.

Most monitoring wells are showing static to slightly increasing trends, likely resulting from decreased pumping during the winter months.

January 2019 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of January 2019. The monthly production average for January 2019 was 131.30 million gallons per day.

The Board of Water Supply rainfall index for the month of January 2019 was 50 percent of normal; with a 5-month moving average of 107 percent. As of February 5, 2019, the Hawaii Drought Monitor shows abnormally dry to moderate drought conditions for the leeward side of Oahu, from Ewa to Waianae. The National Weather Service is forecasting below normal rainfall for February 2019.

Most monitoring wells are showing static to slightly increasing trends, likely resulting from decreased pumping during the winter months.

December 2018 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of December 2018. The monthly production average for December 2018 was 127.52 million gallons per day (mgd).

The Board of Water Supply rainfall index for the month of December 2018 was 89 percent of normal; with a 5-month moving average of 151 percent. As of January 8, 2019, the Hawaii Drought Monitor shows abnormally dry to moderate drought conditions for the leeward side of Oahu, from Ewa to Waianae.

Most monitoring wells are showing increasing trends, likely resulting from decreased pumping during the winter months.

November 2018 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of November 2018. The monthly production average for November 2018 was 128.33 million gallons per day.

The Board of Water Supply rainfall index for the month of November 2018 was 78 percent of normal; with a 5-month moving average of 150 percent. As of December 4, 2018, the Hawaii Drought Monitor shows abnormally dry conditions for the leeward side of Oahu, from Ewa to Waianae.

Most monitoring wells are showing increasing trends, likely resulting from decreased pumping during the winter months.

October 2018 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of October 2018. The monthly production average for October 2018 was 133.04 million gallons per day.

The Board of Water Supply rainfall index for the month of October 2018 was 164 percent of normal; with a 5-month moving average of 153 percent. As of November 6, 2018, the Hawaii Drought Monitor shows no drought conditions for the Island of Oahu.

Most monitoring wells are showing increasing trends, likely resulting from decreased pumping due to increased rainfall as we approach the winter months.

September 2018 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of September 2018. The monthly production average for September 2018 was 136.11 million gallons per day.

The Board of Water Supply rainfall index for the month of September 2018 was 154 percent of normal; with a 5-month moving average of 141 percent. As of October 9, 2018, the Hawaii Drought Monitor shows no drought conditions for the Island of Oahu.

Like the previous month, most monitoring wells are exhibiting static or increasing trends, likely resulting from decreased pumping due to recent storm events.

Most monitoring wells are exhibiting static or increasing trends, likely resulting from decreased pumping during the month due to storm events.

August 2018 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of August 2018. The monthly production average for August 2018 was 147.51 million gallons per day.

The Board of Water Supply rainfall index for the month of August 2018 was 267 percent of normal; with a 5-month moving average of 144 percent. As of September 2018, the Hawaii Drought Monitor downgraded the drought status for Oahu, showing only "abnormally dry conditions" rather than "abnormally dry to moderate drought conditions" for the leeward side of the island.

Most monitoring wells are exhibiting static or increasing trends, likely resulting from decreased pumping during the month due to storm events.

July 2018 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of July 2018. The monthly production average for July 2018 was 150.05 million gallons per day (mgd).

The Board of Water Supply rainfall index for the month of July 2018 was 85 percent of normal; with a five-month moving average of 111 percent. As of August 7, 2018, the Hawaii Drought Monitor shows abnormally dry conditions for the central plain of Oahu and moderate drought conditions for the Leeward coast to the Waianae mountains.

Most monitoring wells are exhibiting static or declining trends due to the increased pumping during the summer season.

June 2018 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of June 2018. The monthly production average for June 2018 was 146.72 million gallons per day.

The Board of Water Supply rainfall index for the month of June 2018 was 94 percent of normal; with a five-month moving average of 132 percent. As of July 10, 2018, the Hawaii Drought Monitor shows abnormally dry conditions for the Leeward side of Oahu.

Most monitoring wells are exhibiting static or declining trends due to the increased pumping during the summer season.

May 2018 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of May 2018. The monthly production average for May 2018 was 135.89 million gallons per day (mgd).

The Board of Water Supply rainfall index for the month of May 2018 was 105 percent of normal; with a five-month moving average of 124 percent. As of June 12, 2018, the Hawaii Drought Monitor shows abnormally dry conditions for the Leeward side of Oahu.

Most monitoring wells are beginning to exhibit static or declining trends due to the increased pumping during the summer season.

April 2018 Groundwater Levels Status Report

There was one aquifer index well (Waialua) within low groundwater status for the production month of April 2018. The monthly production average for April 2018 was 126.93 million gallons per day (mgd).

The Board of Water Supply rainfall index for the month of April 2018 was 168 percent of normal; with a five-month moving average of 124 percent. As of May 8, 2018, the Hawaii Drought Monitor shows no dry conditions for Oahu.

The National Weather Service forecasting favors above normal rainfall for May 2018.

Most monitoring wells are continuing to exhibit static head level trends due to the decreased pumpage in the spring months. Punaluu and Kaluanui wells continued to exhibit larger increases in head levels for April 2018.

March 2018 Groundwater Levels Status Report

There were no aquifer index wells within low groundwater status for the production month of March 2018. The monthly production average for March 2018 was 129.90 million gallons per day (mgd).

The Board of Water Supply rainfall index for the month of March 2018 was 104 percent of normal; with a five-month moving average of 112 percent. As of April 10, 2018, the Hawaii Drought Monitor shows no dry conditions for Oahu.

The National Weather Service forecasting favors above normal rainfall for April, May and June 2018.

February 2018 Groundwater Levels Status Report

There are no aquifer index wells within low groundwater status for the production month of February 2018. The monthly production average for February 2018 was 125.76 million gallons per day.

The Board of Water Supply rainfall index for the month of February 2018 was 187 percent of normal; with a five-month moving average of 110 percent. As of March 13, 2018, the Hawaii Drought Monitor shows no dry conditions for Oahu.

The National Weather Service is forecasting above normal rainfall for April 2018.

Most monitoring wells are continuing to exhibit slightly increasing head level trends due to the decreased pumpage during the winter months.

January 2018 Groundwater Levels Status Report

There was one aquifer index well within low groundwater status for the production month of January 2018. Punaluu has be in caution status since the week of June 18, 2017. The monthly production average for January 2018 was 134.48 million gallons per day (mgd).

The Board of Water Supply rainfall index for the month of January 2018 was 58 percent of normal; with a five-month moving average of 85 percent. As of February 13, 2018, the Hawaii Drought Monitor shows no dry conditions for Oahu.

The National Weather Service (NWS) is forecasting above normal rainfall for March 2018. Because of the La Nina conditions in the equatorial Pacific Ocean, NWS is forecasting above normal rainfall for March, April,and May 2018. 

Most monitoring wells are continuing to exhibit static or slightly increasing head level trends due to the decreased pumping during the winter months.