| The Oregon Department of Environmental Quality (DEQ) completed the Final
Temperature Rule and other Water Quality Standards (Div. 41) Revisions in
December 2003. The Environmental Protection Agency (EPA) approved those revisions
on March 2, 2004. These rule changes were as a result of the court case NWEA
v EPA (March 2003) in which the federal district court of Oregon overturned
EPA's 1999 temperature criteria.
The impact to Oregon includes all point and non-point sources that discharge
into Oregon waters. As a result of these changes, the temperature requirements
are more protective of salmonid species for spawning, migration and rearing.
The new rules have a more stringent antidegradation plan for Oregon streams
and include numeric temperature criteria for specific stream reaches. The
purpose of the temperature criteria is to protect designated temperature
sensitive beneficial uses, including specific salmonid life cycle stages.
The Environmental Quality Commission understands that there are some natural
occurring waters that will not meet the optimal thermal conditions, but
recognizes the importance to minimize additional warming due to human sources.
It is expected that in some cases the control technologies, management practices
and other measures to reduce these negative human effects will be an iterative
process.
Implementation requirements are based on the following:
• The temperature criteria of a stream that has salmon or steelhead
spawning will be applied on a 7-day average maximum temperature such that
it may not exceed 13 degrees C (55.4 degrees F).
• Streams that have salmon and trout rearing or migration may not exceed
18 degrees C (64.4 degrees F) based on the 7-day average maximum temperature.
• Streams identified as migration corridors, the 7-day average maximum
temperature may not exceed 20 degrees C (68 degrees F).
• For point sources that discharge into or above salmon and steelhead
spawning waters that are cooler than the spawning criteria, the stream change
in temperature may not be raised more than 0.5 or 1 degree C, depending on
the 60 day average stream temperatures.
• For point sources, the discharge into temperature quality limited
water is limited to no more than 0.3 degrees C (0.5 degree F) after mixing.
The specific criterion that takes into account air temperature exclusions
and exceptions for very low flow periods.
So - what does this mean for Ashland? Since the completion of the wastewater
treatment plant improvements in 2003, the new plant meets all of DEQ's
requirements for releasing effluent to the creek with the exception of
temperature. The temperature rules have been in flux, along with the Total
Maximum Daily Loads (TMDL) for temperature since 1999. Now that the new
temperature criterion is out, and Ashland is negotiating a permit renewal,
we will have to meet the new requirements. The WWTP effluent will have a
daily thermal load limitation. It is expected that this interim limit will
be reviewed upon the DEQ's completion of a Temperature TMDL (expected by
the summer of 2004). The City is also looking at a basin approach to reducing
thermal loads along the upper reaches of Ashland and Bear Creek. As such,
there will be some time (3-5 years) to evaluate and report on thermal load
reductions as a result of either a wastewater reuse plan or a riparian corridor
improvement plan. Both of these options were included in the City's Temperature
Management Plan that was submitted to DEQ in 2002.
Reuse: The City proposed to develop a market evaluation and water recycling
plan. The planning process will include a public education component about
the water quality of Ashland's effluent as a result of the membrane filtration.
Staff would also evaluate opportunities to increase stream flow by offsetting
irrigation demand. As discussed in the evaluation of reuse options for the
proposed Billings Golf Course (April 7, 2004), there are some unique
possibilities for reuse and water trading to ensure an in-stream water right.
The water trading will meet the Council's intent of keeping water in the
creek. Another option that has not been fully developed is a water trade
with the Talent Irrigation District. This is also something that staff will
continue to explore.
Riparian Plan: Staff suggested that we also develop a riparian corridor
improvement plan and a schedule for implementation along Ashland Creek. The
plan would include temperature modeling to predict the benefits of modifying
the riparian corridor, identification of stream reaches that could benefit
from improvements and develop implementation methods for these improvements.
In addition to temperature improvements, staff expects to see benefits to
riparian habitat, other water quality benefits, aesthetic improvements and
potentially reduced flooding. The city has been successful in requiring standards
for new housing and commercial developments, which include a component for
water quality benefits.
Permit Renewal Timeframe: DEQ will schedule a public hearing for May 2004,
and if all goes well, the permit conditions will go before the Environmental
Quality Commission later this spring. Several of the other parameters have
changed slightly and staff does not see major issues as a result of most
of the other changes. We will continue to work through the process with DEQ. |
