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Looking to find out more about how legacy chemicals like PFAS affect our water source? Learn more here.
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Have more questions regarding the safety of your drinking water provided by GWA? Ask us.
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Visit Guam EPA and find out more about their interim guidance on the island's dieldrin challenges and what it means for all of our water safety use.
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GWA Provides Mitigation Update to Sen. Lujan – Jan. 29, 2026
On January 29, 2026, the Guam Waterworks Authority (GWA) provided the first update on the Authority's dieldrin mitigation efforts following the conclusion of a joint oversight hearing held by the 38th Guam Legislature. In the update to Sen. Jesse A. Lujan, Vice Speaker Tony Ada and Committee on Health Chair Sen. Sabrina Salas Matanane, GWA stated that the Authority " remains firmly committed to our dieldrin mitigation plans, and we appreciate the support from you and your off
nrlee52
5 days ago3 min read
Dieldrin Testing Data from Samples Collected Nov. 11 & Nov. 13
On November 4, GWA had previously reported the status of entry points that tested higher than, or equal to 50% of the IAL for dieldrin. The table below provides a status update to the November 4 reporting with analytical data from samples collected on November 11 and November 13: Residents with questions about their water service or quality can contact GWA Customer Service at 671-647-7800 Monday through Friday from 7:30 a.m. to 6 p.m. and Saturday from 8 a.m. to noon. The Gua
GWA News
Dec 11, 20251 min read
COURTESY BOTTLED WATER DISTRIBUTION FOR SANTA ROSA/YIGO AREA CUSTOMERS ENDING NOV. 12
The Guam Waterworks Authority (GWA) announced today that its courtesy bottled water distribution for customers in the Santa Rosa/Yigo area will conclude on Wednesday, Nov. 12, following four consecutive weeks of sampling and analysis at Well Y-15. Laboratory results of water samples collected on Oct. 11, 16, 23, and 29 all showed non-detect levels for dieldrin in the treated water. These consistent results confirm that the water from Well Y-15 is now safe to drink, cook wi
GWA News
Nov 10, 20251 min read
MULTIPLE TEST RESULTS CONFIRM Y-15 TREATMENT SYSTEM EFFECTIVE, GWA REQUESTS GEPA RESCIND DO NOT DRINK ADVISORY
Today, the Guam Waterworks Authority (GWA) submitted a formal response to the Guam Environmental Protection Agency (EPA), requesting to rescind the “Do Not Drink Without Treatment” advisory for the Santa Rosa/Yigo area. GWA’s letter follows four weeks of comprehensive monitoring, treatment, and testing that confirms GWA’s drinking water from well Y-15 has no detection of dieldrin. Laboratory analysis performed with raw and finished water samples collected on Oct. 11, Oct. 16
GWA News
Nov 7, 20252 min read
Dieldrin IAL Update Release No. 4: FOR THE THIRD WEEK IN A ROW, TEST RESULTS SHOW NO DETECTION OF DIELDRIN AT WELL Y-15, TREATMENT SOLUTION SUCCESSFUL
No dieldrin has been detected at well Y-15 in Yigo after treatment, according to confirmed laboratory analysis after three rounds of testing. The results of “non-detect” continues to affirm the Guam Waterworks Authority’s (GWA) interim treatment system at well Y-15 has successfully removed dieldrin levels. This system, completed on Oct. 10, uses granular activated carbon (GAC) filtration, an EPA-approved and proven technology used to remove contaminants like dieldrin and PFA
GWA News
Nov 4, 20252 min read
Dieldrin IAL Update Release No. 3: TEST RESULTS SHOW NO DETECTION OF DIELDRIN AT WELL Y-15, TREATMENT SOLUTION SUCCESSFUL
No dieldrin has been detected at well Y-15 in Yigo, according to confirmed laboratory analysis after two rounds of testing. The results of “non-detect” affirms the Guam Waterworks Authority’s (GWA) interim treatment system at well Y-15 has successfully removed dieldrin levels. This system, completed on Oct. 10, uses granular activated carbon (GAC) filtration, an EPA-approved and proven technology used to remove contaminants like dieldrin and PFAS from drinking water. Dieldr
GWA News
Oct 29, 20253 min read
GWA RETURNS TO REGULAR CALL CENTER HOURS
Effective immediately, Guam Waterworks Authority (GWA) customer service call center will return to normal hours of Monday through Friday from 7:30 a.m. to 6 p.m. and Saturday from 8 a.m. to noon. Customers can reach the call center at 671-647-7800 / 7803. Additionally, customers may submit questions and service requests to the online customer portal at gwa.custhelp.com at their convenience. The return to normal hours comes after GWA previously offered extended call center
GWA Customer Service
Oct 23, 20251 min read
Dieldrin IAL Update Release No. 2: INTERIM TREATMENT SOLUTION FOR WELL Y-15 COMPLETE AND ONLINE
(Mangilao, GU) — On Oct. 12, the Guam Waterworks Authority (GWA) completed the successful installation of its interim treatment system...
GWA News
Oct 13, 20253 min read
Point of Entry (POE) / Point-of-Use (POU) Filtration System Program Frequently Asked Questions (FAQs)
Application forms available online. Review the FAQ's provided below to help you select the correct application form to submit to GWA. This program provides for GWA supplied NSF 53 or NSF 401 certified POE water filtration systems or reimbursement for qualifying customer-purchased NSF 53 or NSF 401 POE or POU filtration systems to reduce the concentration of dieldrin in supplied water until the GWA’s permanent Granular Activated Carbon (GAC) treatment system is operational at
GWA Customer Service
Oct 10, 20254 min read
New Filling Station Located on Chalan Emsley in Yigo
Affected residents in Yigo/Santa Rosa may visit GWA's newest flexitank filling station on Chalan Emsley with their containers to obtain...
GWA Customer Service
Oct 7, 20251 min read
What is Granular Activated Carbon (GAC) Treatment?
GWA's Surface and Springs Unit recently performed the annual replacement of Granular Activated Carbon (GAC) filters at the Tumon Maui Well. This same type of filtration treatment will be installed at other well sites to filter dieldrin and other contaminants found in the groundwater.
GWA News
Oct 6, 20252 min read
HOAX ALERT: No Boil Water Notice Issued
As of October 5, 2025, no boil water notice for Yigo and Mangilao has been issued by Guam Waterworks Authority (GWA) or Guam...
GWA Customer Service
Oct 5, 20251 min read
Yigo - GWA Water Station Outposts
Affected residents in YIGO who safe water supply may visit any of these water outposts serviced by GWA emergy crews.
GWA News
Oct 3, 20251 min read
GWA General Manager Miguel C. Bordallo addresses timeline of dieldrin response to the Mayors' Council of Guam.
Mayors' Council of Guam Regular Monthly Meeting - October 1, 2025
GWA News
Oct 2, 20251 min read
Courtesy emergency bottled water supply to affected Santa Rosa GWA customers.
GWA in coordination with the Yigo Mayor's office will be providing limited supplies of bottled water to affected customers in the Santa Rosa zones.
GWA News
Oct 2, 20251 min read
GWA Anticipates Interim Treatment System for Y-15 Well by Mid October, Provides Advisory Updates to Customers
Guam Waterworks Authority (GWA) continues prioritizing immediate and long-term treatment solutions for the Y-15 well in Yigo, which has shown elevated levels of dieldrin, a pesticide. GWA has been working on the immediate issues at Y-15 but continues to work proactively on protecting all of GWA’s water sources.
GWA News
Sep 29, 20252 min read
GWA: Elevated Dieldrin Levels Limited to Well Y-15
GWA: ELEVATED DIELDRIN LEVELS LIMITED TO WELL Y-15 ( MANGILAO, GU) —Guam Waterworks Authority (GWA) confirms well Y-15 located in Yigo is...
GWA News
Sep 29, 20251 min read
Drinking Water Warning Do Not Drink without Treatment Advisory
Originally released by GWA on September 8, 2025 (UPDATED: 09/29/2025) The Santa Rosa Area of Northern Water System PWS ID# GU0000006 has...
GWA News
Sep 26, 20253 min read
Governor's Office provides an update
Dieldrin Update as of September 26, 2025 - Correction on Wells, New Hotline.
GWA News
Sep 26, 20251 min read
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