The State of Colorado's Watersheds Report 2005

• Year: 2005
• Title: The State of Colorado's Watersheds Report
• Author: Colorado Watershed Assembly
• Description: 2005
• Publications - Doc Type: Other

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Background
The Bear Creek Watershed
Association is the water quality
management agency for the Bear
Creek Watershed. In 1988, the
group began an intensive one -year
Bear Creek Reservoir Clean Lake
Study. The Association has collected
continuous surface quality and limited
groundwater data since 1990. The Bear
Creek Reservoir Control Regulation
(Regulation #74), updated and expanded
in 2005, defines goals, system of
treatment works, wasteload allocations,
trading program, monitoring and other
control strategies. The Association
implements the control regulation and
produces an annual summary report and
fact sheets (www.bearcreekwatershed.
org). These fact sheets denote annual
water quality within the watershed and
reservoir, as well as long -term trends.
The Association database contains
over 35,000 water quality and
biological data records, including
18 routine parameters. The City of
Lakewood maintains reservoir aeration
and monitoring programs. This aeration
system effectively increases the amount
of dissolved oxygen throughout the
water column, while de- stratifying
the water column. The reservoir de-
stratification causes no measurable
water quality problems. The aeration
system reduces nuisance blue -green
algal blooms and promotes growth of
beneficial green algae.
local watershed reports
Dealing with Drought
In 2002, Bear Creek experienced
the worst drought on record with stream
flow dropping below measurable values
in the middle of the summer. This
naturally caused low flow impacted
trout populations and prompted several
groups to request listing Bear Creek
segment 1 a as temperature and aquatic life
impaired. The Association implemented a
continuous special instream temperature
and ammonia monitoring to document
possible factors affecting trout populations.
The Environmental Protection Agency in
2005 placed Bear Creek on the 303(d)
list of impaired waters as low priority
for temperature and aquatic life use. The
Association will develop and implement a
strategy to address a total maximum daily
load for temperature and determine options
to protect the fishery. A good return of fish
density and numbers (Division of Wildlife
The Association
in 2004)
indicates the
stream will
have a natural
recovery from
the drought
stress. A
three -year
stream data
record shows
temperature
problems are
not typical of
normal flow
conditions.
Current Status
The Association determines if Bear
Creek Reservoir, Turkey Creek and
Bear Creek comply with standards,
classifications and the control
regulation. Management strategies
improve water quality within the
watershed. The reservoir has shifted
from bad (hypertrophic - eutrophic)
toward the preferred eutrophic-
mesotrophic trophic state (good). Major
wastewater treatment plants meet their
specific wasteload allocations. The
reservoir complies with the adopted
narrative standard. The watershed
program evaluates nutrient loading
trends. The 2004 average reservoir
nitrate concentration was 250 ug /l with
a total phosphorus of 32 ug /1. Secchi
depth in 2004 averaged eight feet
and total suspended solids were 5.8
mg /1. Algal productivity measured by
chlorophyll a concentrations averaged
8.5 ug /1 with peak concentrations of 15
ug /1. Reservoir dissolved oxygen trends
were within expected ranges.
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Dealing with Drought
In 2002, Bear Creek experienced
the worst drought on record with stream
flow dropping below measurable values
in the middle of the summer. This
naturally caused low flow impacted
trout populations and prompted several
groups to request listing Bear Creek
segment 1 a as temperature and aquatic life
impaired. The Association implemented a
continuous special instream temperature
and ammonia monitoring to document
possible factors affecting trout populations.
The Environmental Protection Agency in
2005 placed Bear Creek on the 303(d)
list of impaired waters as low priority
for temperature and aquatic life use. The
Association will develop and implement a
strategy to address a total maximum daily
load for temperature and determine options
to protect the fishery. A good return of fish
density and numbers (Division of Wildlife
The Association
in 2004)
indicates the
stream will
have a natural
recovery from
the drought
stress. A
three -year
stream data
record shows
temperature
problems are
not typical of
normal flow
conditions.
Current Status
The Association determines if Bear
Creek Reservoir, Turkey Creek and
Bear Creek comply with standards,
classifications and the control
regulation. Management strategies
improve water quality within the
watershed. The reservoir has shifted
from bad (hypertrophic - eutrophic)
toward the preferred eutrophic-
mesotrophic trophic state (good). Major
wastewater treatment plants meet their
specific wasteload allocations. The
reservoir complies with the adopted
narrative standard. The watershed
program evaluates nutrient loading
trends. The 2004 average reservoir
nitrate concentration was 250 ug /l with
a total phosphorus of 32 ug /1. Secchi
depth in 2004 averaged eight feet
and total suspended solids were 5.8
mg /1. Algal productivity measured by
chlorophyll a concentrations averaged
8.5 ug /1 with peak concentrations of 15
ug /1. Reservoir dissolved oxygen trends
were within expected ranges.