Laboratory Division 

1712 SW 11th Avenue. 

Portland, OR 97201 

Phone: (503) 229-5983 

 (800) 452-4011 

Fax: (503) 229-6037 

Contact: Kevin Masterson 

masterson.kevin@deq.state.or.us 

www.deq.state.or.us 

Fact sheet created 1/2006. 

Pesticide Stewardship 

Partnerships 

Background 

Since 1999, ODEQ has been using a voluntary, 

collaborative approach called Pesticide 

Stewardship Partnerships (PSPs) to identify 

problems and improve water quality associated 

with pesticide use at the local level. The PSP 

approach uses local expertise in combination 

with water quality sampling and toxicology 

expertise of ODEQ to encourage and support 

voluntary changes that cause measurable 

environmental improvements. 

Key Actions 

The key actions of the PSP approach are to: 

1) identify local, pesticide-related water quality 

issues; 2) share results early and often with local 

stakeholders; 3) explain data in relation to effects 

and water quality criteria; 4) engage the 

agricultural community for identifying and 

implementing solutions; and 5) use ongoing 

effectiveness monitoring to measure success and 

provide feedback to support water quality 

management. 

PSPs use both water quality and crop quality as 

measures of success. Pest management and 

water quality management must both be effective 

for long term stewardship of natural resources.

Success Stories 

Working closely with local stakeholders, DEQ 

initially set up two pilot projects in the Columbia 

Gorge Hood River and Mill Creek, ODEQ set 

up PSPs to work collaboratively with local 

stakeholders to assess whether current use 

pesticides were detectable in local surface waters 

at concentrations of concern. In both basins, 

initial data showed repeated detections of 

chlorpyrifos above water quality standards. 

Hood River also showed ambient water quality 

criteria (AWQC) exceedances for azinphos 

methyl and Mill Creek showed exceedances for 

malathion. Local partners, including the fruit 

growers and OSU extension, examined the water 

quality data and made changes to pesticide 

management and application practices. 

Both pilot projects in the Columbia Gorge, Hood 

River and The Dalles, have shown substantial 

improvements in water quality associated with 

measurable changes in pesticide management 

practices. Representative changes for these 

projects may be seen on the graphs on the back 

page. 

Effective Approach for Water Quality 

Protection 

The improvements in water quality and the 

downward trend in organophosphate detections 

seen in the Columbia Gorge pilot projects 

indicate that ODEQ’s innovative PSP approach 

can lead to environmental improvements within 

a two to five year timeframe. While the results 

presented focus on chlorpyrifos and malathion, 

the reductions reflect changes in management 

practices that could reduce effects from other 

current or future use pesticide formulations. 

These early results suggest that the PSP 

approach can be an effective and timely 

alternative to traditional regulatory approaches 

for nonpoint source issues. 

2005/2006 Pilot Projects 

In 2005, based on the early success of the PSP 

approach, DEQ established three new 

partnerships with local stakeholders in the Walla 

Walla, Clackamas and Pudding River basins. 

The land use in these basins include tree fruits, 

row crops, and complex mixed land uses. 

ODEQ has collected one year of sampling data 

in each of these basins to use as baseline data. 

Local partners in each area are actively 

collaborating on the 2006 sampling plans and 

will be evaluating specific changes in 

management practices needed to improve water 

quality while protecting crop quality. ODEQ 

will continue to work closely with local 

stakeholders in each of these basins, providing 

ongoing in-stream monitoring and technical 

support for these projects. 

1n 2006, DEQ will be launching a PSP in the 

Yamhill basin to evaluate whether the PSP 

approach can be used effectively in conjunction 

with TMDL development to restore water 

quality. West Fork Palmer Creek in the Yamhill 

basin is on the 303(d) list for chlorpyrifos. 

For more information on these projects, or if you 

would be interested in starting a Pesticide 

Stewardship Partnership in your watershed, 

contact Kevin Masterson at 503-229-5983 ext. 

260, or email masterson.kevin@deq.state.or.us.

Fact Sheet 
Hood River Pesticide Stewardship Partnership 

The following graph shows results of spring sampling for chlorpyrifos in a small tributary in the Hood River basin, between 2001 and 

2004. The changes in water quality follow changes in pesticide management practices implemented as part of the PSPs. 

The Dalles Pesticide Stewardship Partnership 

The following graph was excerpted from The Fifteenmile Creek Orchard Pesticide Pollution Risk Study 2004 Annual Report. 

They show similar improvement in water quality resulting from voluntary implementation of best management practices. The report 

also presented data showing a concurrent 50% reduction in farmer reported applications of malathion over the study period. 

0.000

0.050

0.100

0.150

0.200

0.250

2001 2002 2003 2004

Year

Chlorpyrifos (ug/L)

0.00

0.10

0.20

0.30

0.40

0.50

0.60

Frequency of Detection

Average Frequency