VancouverVancouver LakeLake andand LakeLake RiverRiver WatershedsWatersheds

SalmonSalmon CreekCreek andand LakeshoreLakeshore

RonRon WierengaWierenga ClarkClark CountyCounty PublicPublic WorksWorks WaterWater ResourcesResources ProgramProgram PresentationPresentation OutlineOutline

¾¾ VancouverVancouver LakeLake andand LakeLake RiverRiver WatershedsWatersheds ¾¾ SalmonSalmon CreekCreek WatershedWatershed andand WaterWater QualityQuality ¾¾ LakeshoreLakeshore WatershedWatershed andand WaterWater QualityQuality ¾¾ DiscussionDiscussion ofof SignificanceSignificance ofof InputsInputs toto VancouverVancouver LakeLake

GeneralGeneral DepictionDepiction ofof WaterWater QualityQuality ProblemsProblems Department of Ecology 303d Listed Waterways in Lake River System

¾ z Phosphorus, fecal coliform, PCB’s ¾ Lake River z Temperature, fecal coliform ¾ Salmon Creek z Oxygen, pH, temperature, fecal coliform, turbidity ¾ Whipple Creek z Fecal coliform ¾ z Oxygen, fecal coliform, temperature Area of 90 square miles Mixed land use Five major tributaries and many smaller streams Extensive storm water infrastructure in lower watershed Impervious surfaces greater than 50% in lower watershed

Annual Volume 105,000 acre-ft per year Average flow = 145 cfs Range = 15 to 1,510 cfs SalmonSalmon CreekCreek InputsInputs toto LakeLake RiverRiver

Parameter Median Value Range Comment

Typically higher 80 bac-t per Fecal Coliform 2 to 500 concentration at low 100mL flow

Total 0.034 to Higher concentration 0.055 mg/L Phosphorus 0.132 at low flow

Water 7-day moving 75 deg-F varies Temperature average daily max

0.76 to Nitrogen 1.20 mg/L Inorganic nitrogen 2.64 Area of 3.6 square miles Urban, mostly residential land use Small streams and springs Similar to Cougar and Cold Creeks Extensive storm water infrastructure draining to streams as well as the lake Impervious surfaces greater than 50% LakeshoreLakeshore WaterWater QuantityQuantity andand QualityQuality ¾¾ VeryVery limitedlimited waterwater qualityquality datadata ¾¾ SWWHDSWWHD datadata fromfrom latelate 19701970’’ss

z VeryVery highhigh fecalfecal coliformcoliform andand nutrientnutrient levelslevels inin ChickenChicken CreekCreek (southern(southern--mostmost inin LakeLake Shore.Shore. ¾¾ AnnualAnnual runoffrunoff volumevolume basedbased onon rainfallrainfall andand amountamount ofof impervious*impervious* ofof landland surfacesurface estimatedestimated atat 3,5003,500 acreacre--ftft perper yearyear

*Total impervious surfaces in Lake Shore watershed based on land cover data from satellite imagery in 2000; digital data from Clark County Water Resources. EstimatedEstimated LakeshoreLakeshore TributaryTributary InputsInputs toto VancouverVancouver LakeLake Median Parameter Range Comment Value

400 bac-t 0 to Fecal Coliform Highly variable per 100mL 15,000

Total 0.050 to Higher concentration 0.090 mg/L Phosphorus 0.400 at low flow

Water 65 deg-F varies Typical max values Temperature

0.60 to Higher concentration Nitrogen 2.0 mg/L 4.0 at low flow Water quality parameters are estimated using averages observed at Cougar Creek (2002-2004) and Cold Creek (1991-1998) OtherOther WaterWater QualityQuality ConsiderationsConsiderations forfor SalmonSalmon CreekCreek andand LakeshoreLakeshore TributariesTributaries

¾ StreamsStreams areare highlyhighly influencedinfluenced byby stormstorm waterwater runoff:runoff:

z Typical storm water pollutants for given land uses including fine suspended material, suspended sediments, metals, pesticides, and other pathogens;

z Higher loads of pollutants carried to the lake. ¾ GroundGround waterwater qualityquality inin urbanurban areasareas influencesinfluences nutrientnutrient andand bacteriabacteria concentrations.concentrations. DiscussionDiscussion ofof InputsInputs toto thethe LakeLake Understanding the workings of the lake and Lake River system is a prerequisite for discussing the impact of water quality and quantity from specific watersheds

¾ Data Availability z Clark County Water Resources – quantity and quality of Whipple and Salmon Creeks. z City of Vancouver – quantity and quality of Burnt Bridge Creek. z Pre- and Post- restoration data sets. ¾ Data Quality z Are the existing data sets representative of current conditions? BBC and Lakeshore examples. ¾ Data Gaps z Annual volumes of water entering the lake from Lake River, the Columbia RivRiverer via the flushing channel, and groundwater. z Water quality of Lake River, Lakeshore tributaries, and groundwater HydrologyHydrology ofof VancouverVancouver LakeLake

¾ HydrologyHydrology isis controlledcontrolled byby thethe stagestage ofof thethe ColumbiaColumbia River:River:

z October - Lowest lake and tributary levels; Lake River reverses daily due to tidal fluctuations.

z November to February - lake level rises to intermediate levels as BBC and SC flows increase rapidly; Lake River reverses flow for days at a time.

z January - Tributary flows peak in January and lake water is dominated by flows other than the . HydrologyHydrology ofof VancouverVancouver LakeLake

¾ HydrologyHydrology isis controlledcontrolled byby thethe stagestage ofof thethe ColumbiaColumbia River:River:

z April to June – Columbia River rises due to snowmelt, highest water levels mid-June; flow in Lake River is typically south into the lake.

z June to July – lake level drops rapidly; flow in Lake River is to the north carrying water away from the lake.

z July to November – Lake remains at a low level; flow in Lake River reverses daily. HydrologyHydrology ofof VancouverVancouver LakeLake

¾ A - Salmon Creek z ~100,000 acre-ft per year (Clark County data) ¾ E – Burnt Bridge Creek z ~15,000 acre-ft per year (Cooper Cons., 1985) ¾ Lakeshore (not shown) z ~3,500 acre-ft per year (Clark County estimates)

*Graphic from Bhagat and Orsborn, 1971 HydrologyHydrology ofof VancouverVancouver LakeLake

¾ C – Groundwater

z 15,000 acre-ft per year (Bhagat and Orsborn, 1971) ¾ D - Precipitation

z 8,700 acre-ft per year (Clark County data)

*Graphic from Bhagat and Orsborn, 1971 HydrologyHydrology ofof VancouverVancouver LakeLake

¾ B – Lake River

z Annual volume unknown

z Instantaneous measures range from 150 to 300 cfs to and from the laklakee ¾ Flushing channel (not shown)

z Annual volume unknown

z Instantaneous measures range from 75 to 300 cfs depending on lake level.

*Graphic from Bhagat and Orsborn, 1971 HydrologyHydrology ofof VancouverVancouver LakeLake

¾ Lake River, Salmon Creek, and the Columbia River are likely the most significant contributors of water. ¾ Other smaller tributaries and groundwater may be significant sources of pollutants.

*Graphic from Bhagat and Orsborn, 1971