Ground level spraying conducted by the City is done by licensed professionals using pesticide that is EPA-approved as being safe for humans and the environment. The City uses its CodeRED system to notify residents in the areas that will be sprayed. 

October 27, 2025

Tarrant County has notified the City of Colleyville on Monday, October 27, 2025 of positive test results for West Nile Virus in 1of the 6 submitted mosquito samples for the week of October 23, 2025. The sample that tested positive for West Nile virus was taken from the vicinity of 6500 Pleasant Run Road. This is the 19th sample that has tested positive for West Nile Virus in 2025.The test site will be treated with larvicide and is scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED.

October 20, 2025

Tarrant County has notified the City of Colleyville on Monday, October 20, 2025 of positive test results for West Nile Virus in 2 of the 6 submitted mosquito samples for the week of October 16, 2025. The samples that tested positive for West Nile virus were taken from the vicinities of 1600 Hall Johnson and 2500 Glade Road. This is the 18th sample that has tested positive for West Nile Virus in 2025 .The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This triggers truck mounted fogging for these locations. Fogging is planned for Tuesday and Wednesday night, weather permitting.

October 13, 2025

Tarrant County has notified the City of Colleyville on Monday, October 13, 2025 of positive test results for West Nile Virus in 3 of the 6 submitted mosquito samples for the week of October 9, 2025. The samples that tested positive for West Nile virus were taken from the vicinities of 300 LD Lockett, 1600 Hall Johnson and 4100 Windermere Court. This is the 16th sample that has tested positive for West Nile Virus in 2025.The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This triggers truck mounted fogging for these locations. Fogging is planned for Tuesday and Wednesday night, weather permitting.

October 6, 2025

On October 6, 2025, the Tarrant County Health Department notified the City of Colleyville of a positive human case for West Nile Virus. The location of the case is not specifically known; only the closest trap site address was given for reference point. The trap site is located at 6800 Milton Drive and that location has not tested positive a single time this mosquito season. It is unknown if this resident contracted the virus in Colleyville or in another location.  In order to help protect residents of Colleyville from contracting West Nile, the city will use truck mounted fogging on Tuesday night, October 7, weather permitting.  The area to be fogged will be approximately a half mile radius from the trap site located at 6800 Milton Drive.  The City of Colleyville will also treat area with larvicide and provide continue treatment and testing throughout the city.   

October 1, 2025

Tarrant County has notified the City of Colleyville on Wednesday, October 1, 2025 of positive test results for West Nile Virus in 3of the 6 submitted mosquito samples for the week of September 24, 2025. The samples that tested positive for West Nile virus were taken from the vicinities of 5200 Bransford Road, 200 McDonwell School Road, and 4100 Windermere Court. This is the 13th sample that has tested positive for West Nile Virus in 2025.The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This triggers truck mounted fogging for these locations. Fogging is planned for Thursday night, weather permitting.

September 25, 2025

On September 25, 2025, the Tarrant County Health Department notified the City of Colleyville that a Colleyville resident has tested positive for West Nile Virus. The location of the case is not specifically known; only the closest trap site address was given for reference point. It is unknown if this resident contracted the virus in Colleyville or in another location.  In order to help protect residents of Colleyville from contracting West Nile, the city will use truck mounted fogging Friday night, September 26th, between 9:00pm and 5:00am.  The area to be fogged will be approximately a half mile radius from the nearest trap site located at 5201 Bransford Road.  The City of Colleyville will also treat area with larvicide and provide continue treatment and testing throughout the city.   

September 8, 2025

Tarrant County has notified the City of Colleyville on Monday, September 8, 2025 of positive test results for West Nile Virus in 2 of the 6 submitted mosquito samples for the week of September 4, 2025. The samples that tested positive for West Nile virus were taken from the vicinities of 5200 Bransford Road and 4100 Windermere Court. This is the 10th sample that has tested positive for West Nile Virus in 2025.The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This is the 4th positive at Bransford Road . We will be fogging areas 2 nights in a row, planned for Tuesday and Wednesday night between 9:00 PM and 5:00 AM, weather permitting.

September 2, 2025

Tarrant County has notified the City of Colleyville on Tuesday, September 2, 2025 of a positive test result for West Nile Virus in 1 of the 6 submitted mosquito samples for the week of August 27, 2025. The sample that tested positive for West Nile virus was taken from the vicinity of 200 McDonwell School Rd. This is the 8th sample that has tested positive for West Nile Virus in 2025.The test site will be treated with larvicide and is scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This triggers truck mounted fogging for this location. The fogging is planned for Wednesday night, weather permitting.

August 25, 2025

Tarrant County has notified the City of Colleyville on Monday, August 25, 2025 of a positive test result for West Nile Virus in 1 of the 6 submitted mosquito samples for the week of August 21, 2025. The sample that tested positive for West Nile virus was taken from the vicinity of 5200 Bransford Road. This is the 7th sample that has tested positive for West Nile Virus in 2025.The test site will be treated with larvicide and is scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This triggers truck mounted fogging for this location. The fogging is planned for Tuesday night, weather permitting.

August 18, 2025

Tarrant County has notified the City of Colleyville on Monday, August 18, 2025 of positive test results for West Nile Virus in 2 of the 6 submitted mosquito samples for the week of August 14, 2025. The samples that tested positive for West Nile virus were taken from the vicinity of 5200 Bransford Road and 200 McDonwell School Road. This is the 6th sample that has tested positive for West Nile Virus in 2025.The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This triggers truck mounted fogging for these locations. The fogging is planned for Tuesday night, weather permitting.

August 11, 2025

Tarrant County has notified the City of Colleyville on Monday, August 11, 2025 of positive test results for West Nile Virus in 3 of the 6 submitted mosquito samples for the week of August 8, 2025. The samples that tested positive for West Nile virus were taken from the vicinity of 1600 Hall-Johnson, 5200 Bransford Road, and 200 McDonwell School Road. This is the 4th sample that has tested positive for West Nile Virus in 2025.The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This triggers truck mounted fogging for these locations. The fogging is planned for Tuesday night, weather permitting.

July 22, 2025

Tarrant County has notified the City of Colleyville on Tuesday, July 22, 2025 of positive test results for West Nile Virus in 1 of the 5submitted mosquito samples for the week of July 10, 2025. The sample that tested positive for West Nile virus was taken from the vicinity of 1600 Hall-Johnson. This is the 1st sample that has tested positive for West Nile Virus in 2025.The test site will be treated with larvicide and is scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED.

October 14, 2024

Tarrant County has notified the City of Colleyville on Monday, October 14, 2024 of positive test results for West Nile Virus in 1 of the 6 submitted mosquito samples for the week of October 9, 2024. The sample that tested positive for West Nile virus was taken from the vicinity of 5200 Bransford Road. This is the 32nd sample that has tested positive for West Nile Virus in 2024.The test site will be treated with larvicide and is scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This triggers truck mounted fogging for this location, planned for Tuesday night weather pemitting.

September 30, 2024

Tarrant County has notified the City of Colleyville on Monday, September 30, 2024 of positive test results for West Nile Virus in 2 of the 6 submitted mosquito samples for the week of September 25, 2024. The samples that tested positive for West Nile virus were taken from the vicinities of 240 McDonwell School Road and 6500 Pleasant Run Rd. This is the 31st sample that has tested positive for West Nile Virus in 2024.The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This triggers truck mounted fogging for these locations, planned for Tuesday night weather pemitting.

September 16, 2024

Tarrant County has notified the City of Colleyville on Monday, September 16, 2024 of a human case of West Nile virus in the area of McDonwell School Road. This area is scheduled for a fogging event on September 17, 2024. This is the 6th human case of WNV in Colleyville.

September 10, 2024

Tarrant County has notified the City of Colleyville on Tuesday, September 10, 2024 of a human case of West Nile virus in the area of Hall-Johnson. This area is scheduled for a fogging event on September 10, 2024.

September 9, 2024

Tarrant County has notified the City of Colleyville on Monday, September 9, 2024 of a positive test result for West Nile Virus in 2 of the 6 submitted mosquito samples for the week of September 4, 2024. The samples that tested positive for West Nile virus were taken from the vicinities of 5200 Bransford Rd and 4300 Bedford Rd. This is the 29th sample that has tested positive for West Nile Virus in 2024.The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile of the sample area will be notified by CodeRED. This triggers truck mounted fogging for these locations.

September 6, 2024

Tarrant County has notified the City of Colleyville on Friday, September 6, 2024 of a human case of West Nile virus in the area of Milton Dr . This area is scheduled for a fogging event on September 7, 2024.

September 5, 2024

Tarrant County has notified the City of Colleyville on Thursday September 5, 2024 of a human case of West Nile virus in the area of W LD Lockett . This area is already scheduled for a fogging event tonight September 5, 2024.

September 3, 2024

Tarrant County has notified the City of Colleyville on Tuesday, September 3, 2024 of a positive test result for West Nile Virus in 1of the 6 submitted mosquito samples for the week of August 29, 2024. The sample that tested positive for West Nile virus was taken from the vicinity of 300 W LD Lockett. This is the 27th sample that has tested positive for West Nile Virus in 2024.The test site will be treated with larvicide and is scheduled for continued treatment and testing. Residents within a quarter-mile of the sample area will be notified by CodeRED. This triggers truck mounted fogging for this location.

August 19, 2024

Tarrant County has notified the City of Colleyville on Monday, August 19, 2024 of a positive test result for West Nile Virus in 5 of the 6 submitted mosquito samples for the week of August 14, 2024. The samples that tested positive for West Nile virus were taken from the vicinities of 3200 Queensbury Way, 500 Forest Meadow, 200 McDonwell School Road, 1600 Hall Johnson, and 4100 Windermere. This is the 26th sample that has tested positive for West Nile Virus in 2024.The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile of the sample area will be notified by CodeRED. This triggers truck mounted fogging for these locations planned for Tuesday night, weather permitting.

August 12, 2024

Tarrant County has notified the City of Colleyville on Monday, August 12, 2024 of a positive test result for West Nile Virus in 1 of the 6 submitted mosquito samples for the week of August 8, 2024. The sample that tested positive for West Nile virus was taken from the vicinity of 5200 Bransford Road. This is the 21st sample that has tested positive for West Nile Virus in 2024.The test site will be treated with larvicide and is scheduled for continued treatment and testing. Residents within a quarter-mile of the sample area will be notified by CodeRED. This triggers truck mounted fogging for this location planned for Tuesday night, weather permitting.

August 5, 2024

Tarrant County has notified the City of Colleyville on Monday, August 5, 2024 of positive test results for West Nile Virus in 4of the 6 submitted mosquito samples for the week of August 1, 2024. The samples that tested positive for West Nile virus were taken from the vicinities of 5200 Bransford Road, 4100 Windemere, 300 W LD Lockett, and 1600 Hall-Johnson Road. This is the 20th sample that has tested positive for West Nile Virus in 2024.The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This triggers truck mounted fogging for these locations planned for Tuesday night, weather permitting.

July 29, 2024

Tarrant County has notified the City of Colleyville on Monday, July 29, 2024 of positive test results for West Nile Virus in 5 of the 6 submitted mosquito samples for the week of July 25, 2024. The samples that tested positive for West Nile virus were taken from the vicinities of 5200 Bransford Road, 2200 Broadoak Way 3200 Scarborough, 240 McDonwell School Road, and 1600 Hall-Johnson Road. This is the 16th sample that has tested positive for West Nile Virus in 2024.The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This triggers truck mounted fogging for these locations planned for Tuesday night, weather permitting.

July 22, 2024

Tarrant County has notified the City of Colleyville on Monday, July 22, 2024 of positive test results for West Nile Virus in 5 of the 6 submitted mosquito samples for the week of July 18, 2024. The samples that tested positive for West Nile virus were taken from the vicinities of 5200 Bransford Road, 4100 Windermere, 6800 Milton Dr, 3700 Briarhaven Ln, and 1600 Hall-Johnson. This is the 11th sample that has tested positive for West Nile Virus in 2024.The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile of the sample areas will be notified by CodeRED. This triggers truck mounted fogging for these locations planned for Tuesday night, weather permitting. The City was also notified of two human cases of WNV.

July 8, 2024

Tarrant County has notified the City of Colleyville on Monday, July 8, 2024 of positive test results for West Nile Virus in 4 of the 6 submitted mosquito samples for the week of July 2, 2024. The samples that tested positive for West Nile virus were taken from the vicinities of 5200 Bransford Road, 3200 Queensbury Way, 500 Forest Meadow, and 1600 Hall-Johnson Rd.. This is the 6th sample that has tested positive for West Nile Virus in 2024. This triggers truck mounting fogging for these locations. The fogging is planned for this week, weather permitting.

July 1, 2024

Tarrant County has notified the City of Colleyville on Monday, July 1, 2024 of positive test result for West Nile Virus in 1 of the 6 submitted mosquito samples for the week of June 27, 2024. The sample that tested positive for West Nile virus was taken from the vicinity of 5200 Bransford Road. This is the 2nd sample that has tested positive for West Nile Virus in 2024. The test site will be treated with larvicide and is scheduled for continued treatment and testing.

June 10, 2024

Tarrant County has notified the City of Colleyville on Monday, June 10, 2024 of positive test result for West Nile Virus in 1 of the 6 submitted mosquito samples for the week of June 7, 2024. The sample that tested positive for West Nile virus was taken from the vicinity of 5200 Bransford Road. This is the 1st sample that has tested positive for West Nile Virus in 2024. The test site will be treated with larvicide and is scheduled for continued treatment and testing.

October 30, 2023

Tarrant County has notified the City of Colleyville on Monday, October 30, 2023 of positive test result for West Nile Virus in 1of the 6 submitted mosquito samples for the week of October 26, 2023. The sample that tested positive for West Nile virus was taken from the vicinity of 5200 Bransford Road. This is the 10th sample that has tested positive for West Nile Virus in 2023.The test site will be treated with larvicide and is scheduled for continued treatment and testing.

July 31, 2023

Tarrant County has notified the City of Colleyville on Monday, July 31, 2023 of positive test results for West Nile Virus in 2 of the 6 submitted mosquito samples for the week of July 27, 2023. The samples that tested positive for West Nile virus were taken from the vicinity of 6811 Milton Dr. and 3700 Briarhaven. This is the 9th sample that has tested positive for West Nile Virus in 2023. These results trigger targeting fogging for these locations. Fogging is planned for Wednesday night, weather permitting.

July 3, 2023

Tarrant County has notified the City of Colleyville on Monday, July 3, 2023 of positive test results for West Nile Virus in 2 of the 6 submitted mosquito samples for the week of June 30, 2023. The samples that tested positive for West Nile virus were taken from the vicinity of 200 McDonwell School Road and 3200 Scarborough Ln E. This is the 7th sample that has tested positive for West Nile Virus in 2023.

June 20, 2023

Tarrant County has notified the City of Colleyville on Tuesday, June 20, 2023 of positive test results for West Nile Virus in 2 of the 6 submitted mosquito samples for the week of June 15, 2023. The samples that tested positive for West Nile virus were taken from the vicinity of 1600 Hall Johnson Road and 2200 Broadoak Way. This is the 5th sample that has tested positive for West Nile Virus in 2023.

The test sites will be treated with larvicide and are scheduled for continued treatment and testing. Residents within a quarter-mile area of the sample area will be notified by CodeRED. These locations will also receive UTV fogging, scheduled for Wednesday evening, June 21, weather permitting.

June 12, 2023

Tarrant County has notified the City of Colleyville on Monday, June 12, 2023 of a positive test result for West Nile Virus in 1 of the 6 submitted mosquito samples for the week of June 8, 2023. The sample that tested positive for West Nile virus was taken from vicinity of 1600 Hall Johnson Rd. This is the 3rd sample that has tested positive for West Nile Virus in 2023.

The test site will be treated with larvicide and is scheduled for continued treatment and testing. Residents within a quarter-mile area of the sample area will be notified by CodeRED. 

May 30, 2023

Tarrant County has notified the City of Colleyville on Tuesday, May 30, 2023 of a positive test result for West Nile Virus in 1 of the 6 submitted mosquito samples for the week of May 26, 2023. The sample that tested positive for West Nile virus was taken from vicinity of 6500 Pleasant Run. This is the 2nd sample that has tested positive for West Nile Virus in 2023.

The test site will be treated with larvicide and is scheduled for continued treatment and testing. Residents within a quarter-mile area of the sample area will be notified by CodeRED. 

May 22, 2023

Tarrant County has notified the City of Colleyville on Monday, May 22, 2023 of a positive test result for West Nile Virus in 1 of the 6 submitted mosquito samples for the week of May 19, 2023. The sample that tested positive for West Nile virus was taken from vicinity of 2500 Glade Road. This is the 1st sample that has tested positive for West Nile Virus in 2023.

The test site will be treated with larvicide and is scheduled for continued treatment and testing. Residents within a quarter-mile area of the sample area will be notified by CodeRED.