HomeMy Public PortalAboutOrd. 572 Phosphorous Detergent Ban FindingsMcCALL ORDINANCE 572
PHOSPHOROUS DETERGENT BAN
FINDINGS
INTRODUCTION
On July 12, 1990 the City of McCall passed Ordinance 572 which
bans the commercial sale of household cleaning products
containing more than a trace level of phosphorous within the city
limits. The purpose of this document is to summarize findings
which lead to the development and passage of Ordinance 572.
SOURCES
The City of McCall lies within the Payette River watershed on the
banks of Big Payette Lake. Discharge from Big Payette Lake is
through the North Fork Payette River which flows south to Cascade
Reservoir. The McCall Sewage Treatment Plant discharges effluent
to the North Fork Payette River.
Cascade Reservoir is experiencing accelerated degradation of
water quality: Several studies have identified phosphorous as the
major factor in the process. The phosphorous loading in Cascade
Reservoir is due to point and non -point sources.
The Draft Cascade Reservoir Watershed -Water Quality Management
Plan. (Entranco May 1990) identifies two point sources for
phosphorous in Cascade Reservoir; the McCall Sewage Treatment
Facility and McCall Fish Hatchery. The McCall Sewage Treatment
Facility is identified as contributing 5,160 kg P/year to Cascade
Reservoir which is 11 percent of the total phosphorous loading.
Page 1.6 of the Draft Plan states "A specific objective of future
reservoir management is to reduce existing phosphorous loading
and not allow any additional phosphorous loading to Cascade
Reservoir". Page 4.1 of the Draft Plan states "Upgrade of the
McCall sewage treatment plant to reduce phosphorous loading on a
seasonal or annual basis" as a point source control option. It is
anticipated that the Steering Committee will recommend that
phosphorous removal efficiencies of 95-100 percent be imposed
upon the McCall Sewage Treatment Facility.
Section I.0 of the McCall NPDES Permit No. ID-002023-1 is a
"Reopener Clause" which allows phosphorous effluent limitations
if recommended in the final Phase I Clean Lakes Study for Cascade
Reservoir.
The McCall Sewage'Treatment Facility has been identified as a
point source contributing ).1 percdpt of the phosphorous load to
Cascade Reservoir. The requirement for 95-100 percent removal of
phosphorous from the effluent discharge will likely occur in the
near future.
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DYNAMICS OF NUTRIENT REMOVAL, USE AND DISPERSAL
The Draft Cascade Reservoir Watershed -Water Quality Management
Plan (Entranco May 1990) outlines the dynamics of nutrient
Removal, Use and Dispersal within Cascade Reservoir. The dynamics
of nutrient removal, use and dispersal in the McCall Wastewater
Treatment Facility consist of two major categories; remove the
source of the phosphorous and remove the phosphorous from the
effluent stream through the treatment process.
Typical raw sewage contains 10-15 mg/1 total phosphorous. Of this
3-4 mg/1 are organic and 7-11 mg/1 are inorganic forms. The
sources of this phosphorous include human body wastes, food
wastes, and condensed inorganic phosphate compounds used in
various household detergents.
The McCall Sewage Treatment Facility consists of three lagoons
(two of which are aerated), chlorination and discharge to the
North Fork Payette River. The treatment facility also has four
slow -rate sand filters. Phosphorous removal at the present
facility is accomplished through assimilation into algae cells
and precipitation in the lagoons; and through filtration and
fixation in the sand filters.
PREVENTATIVE OR REMEDIAL ACTIONS
Two actions may be taken to reduce or eliminate phosphorus for
the effluent discharged by McCall's Sewage Treatment Facility.
Remove the source of the phosphorous and increase phosphorous
removal efficiency in the facility.
Source removal may consist of reduction in the incoming waste
stream and reduction of the phosphorous concentration in that
stream. A reduction in the inorganic forms of phosphorous in the
waste stream throughthe use of low phosphate detergents is a
proven method. This is the only action that may be taken which
will result in an immediate phosphorous reduction.
Increasing phosphorous removal efficiency in the McCall Sewage
Treatment Facility may be accomplished through a change in
operational procedures and or a treatment plant upgrade. Each of
these options will take a detailed study of the facility
requiring several months or years for implementation.
FINDINGS SUMMARY
Cascade Reservoir is experiencing accelerated degradation of
water quality. Reservoir phosphorous concentrations are
identified as the major factor in the process. The City of McCall
Wastewater Treatment Facility is identified as a point source
contributing 11 percent of:the annual phosphorous load to Cascade
Reservoir. Reduction of tOiis load fill be required by regulatory
agencies in the near future.
The City of McCall has two methods to accomplish this reduction.
They may reduce the source of phosphorous in the waste stream.
They may increase removal efficiency in the treatment process.
The City should move forward with both methods immediately.
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Implementation of a phosphate detergent ban will provide an
immediate reduction in the incoming phosphorous loading to
the existing facility. Other communities have experienced
20-40 percent phosphorus reductions using similar bans. This
is a cost effective measure which will cause immediate
results if implemented.
The City should investigate increasing treatment process
removal efficiency. This will be accomplished through a
Facility Plan Update scheduled to begin in late 1990.
Adopted by motion of the McCall City Council, November 8,
1990.
Mayor
ATTEST:
Arthur J. Schmidt
City Adm nistrator