|Location||Whatcom County, Washington|
|Primary outflows||Whatcom Creek|
|Catchment area||145 km²|
|Basin countries||United States|
|Max. length||13mi or 16.1km|
|Max. depth||350 ft (110 m)|
|Surface elevation||314 ft (96 m)|
|Islands||1 (Reveille Island)|
|This article needs additional citations for verification. (October 2012)|
Lake Whatcom (from the Lummi word for "loud water") is located in Whatcom County, Washington. It is the drinking water source for approximately 85,000 residents in the City of Bellingham as well as Whatcom County. It is approximately 10 miles total in length and 1 mile in width at its widest. Lake Whatcom is located and managed within 3 political jurisdictions, the City Of Bellingham, Whatcom County and Lake Whatcom Water and Sewer District. The lake is a popular source of motor boating, swimming, fishing and other recreational activities.
The lake is divided into three basins. Basin 1, the Silver Beach Basin is the furthest north, and has a maximum depth of 100 feet (30 m). Land use in Basin 1 is primarily residential development, with one large park and several small parks. Basin 2, the Geneva Basin is the central basin where the drinking water for the city of Bellingham is withdrawn. This basin is the shallowest, with a maximum depth of just 40–60 feet (12–18 m). Land use is still primarily residential with a mix of lake protection program properties and some rural forestry. Basin 3 is the southernmost basin, and is the most remote. At its greatest depth basin 3 is 328 feet (100 m) deep, and is estimated to contain 96% of the lake's total water volume. Land use in Basin 3 is composed of scattered residential development, mostly in the community of Sudden Valley, as well as rural and commercial forestry. The total area of the Lake Whatcom Watershed is 142 square kilometers (or 56 square miles).
There are 9 annual streams and approximately 25 additional small creeks and tributaries that flow into Lake Whatcom. Accounting for 23 sub-watersheds in all. Lake Whatcom drains into Bellingham Bay by way of Whatcom Creek.
The lake has only one island, the 3-acre (12,000 m2) Reveille Island, owned by Camp Firwood, which is believed to be the site of past ceremonies by Native Americans, due to the presence of pictographs and a zoomorphic stone bowl found on the island.
The earliest known settlement was a Northwest Coast Salish village at the south end of the lake, occupied by the Saquantch tribe. Around 1800 the Saquantch were pushed out by the Lummi tribe. In the 1850s is the first known settlement of Westerners to Lake Whatcom. The first claim of private land was reported for $8. Most of the area surrounding the lake was extensively logged by the end of the 19th century. Large mining operations also existed near the lake from the late 19th century through 1919, when the Whatcom Mining Company closed down. In 1946 J.H. Donovan donates 12.5 acres to the city for what would eventually become Bloedel Donovan Park. In 1962 water is diverted from the Middle Fork of the Nooksack to augment water levels.
As a drinking water source, Lake Whatcom’s quality is in compliance for all tested chemicals, bacteria and turbidity.  Bellingham is a participant in the Partnership for Safe Water and the City’s drinking water also meets the higher standards set by this group. For the past 10 years the City of Bellingham Public Works has received the Partnership for Safe Water’s Director Award for commitment to providing safe drinking water. 
Lake Whatcom was placed on the Environmental Protection Agency’s 303(d) list for impaired water bodies in 1998, due to low dissolved oxygen (DO) levels. Low Dissolved oxygen are directly related to the amount of phosphorus Lake Whatcom receives. Low DO levels do not directly affect drinking water quality. As required by the 303(d) listing, The Washington State Department of Ecology (DOE) created a computer model to find the Total Maximum Daily Load (TMDL) of phosphorus the lake can receive while maintaining adequate dissolved oxygen levels. In 2008 the DOE estimated that in order to achieve acceptable levels of DO, impervious/run off surfaces need to be returned to pre-1988 levels.
Most of the Phosphorus enters the lake through non point sources. Water runoff from lawns, gardens and streets contain high levels of phosphorus. Aging septic systems in the water can leach phosphorus into the water body. In 2005 fertilizers containing phosphorus were banned to try to reduce the amount of phosphorus entering the lake. The City of Bellingham and Whatcom county have also restricted development activities such as land clearing, from October 1 through May 31 annually to prevent runoff from exposed soil during high precipitation months.
Pet waste also contributes to the pollutant load in the Lake Whatcom watershed. Pet waste contains high levels of fecal coliform which has caused high pollution in 11 of the 22 tributaries running into the lake. A TMDL has been created for these as well. 
A 2010-2014 Work Plan for Lake Whatcom was recently approved by the councils of the City of Bellingham, Whatcom County and Water District 10. The Work Plan can be found at http://www.lakewhatcom.whatcomcounty.org/UserFiles/File/WorkPlans/Draft_LW_2010_2014%20Work%20Plan%20Staff%20Final.pdf
Lake Whatcom is a monomictic lake. The water body is stratified for part of the year (late spring through mid-fall) and mixed during the rest. This phenomenon is important to the hydrology of the lake. The top layer of water (epilimnion) is warmed by the sun and sits atop the metalimnion (also a thermocline). In this middle layer water temperatures take a pronounced decline and eventually a distinct third layer forms (hypolimnion), much colder and isolated from the rest of the water body. Minimal oxygen from the air diffuses down to the hypolimnion, causing very low dissolved oxygen (DO) levels. This combined with sediment oxidation, cause for near or complete anoxic conditions in the deeper levels of the lake. This stratification is more pronounced in Basin 3 where water is deepest. This layering of the lake, as well as the distinct physical barriers (sills) between basins cause for slow movement of water through the lake. (Ecology TMDL, 2008)
Another important hydrological phenomenon on Lake Whatcom is the occurrence of seiches. A seiche is the slow sloshing of water from one side of the lake to the other, due to winds in Lake Whatcom’s case. Winds will push water to one side of the lake, causing water levels to rise on one end and lower on the other. When the wind stops, the water rebounds back and forth until it is settled again. This up and down movement of the water causes the thermocline to rise and fall as well, which can result in the cold, anoxic water from Basin 3, to spill over the Strawberry Sill into Basin 2.
Major outputs of lake water are Whatcom Creek (77.5% of outflow), City of Bellingham intake (11.3%), evaporation (7.9%) and hatchery (2.5%). The estimated residence time of water entering the lake until it leaves is 7.4 years. (Lake Whatcom Annual Report, 2008/09 http://ceratium.ietc.wwu.edu/IWS2)
Washington State defines invasive species as “invasive species include non-native organisms that cause economic or environmental harm and are capable of spreading to new areas of the state. Invasive species does not include domestic livestock, intentionally planted agronomic crops, or non-harmful exotic organisms” (Revised Code of Washington 79A.25.310). Invasive species can be spread by various means including: boats/boat trailers, animals, on boots and in clothing. Sometimes species will be introduced intentionally, however this is rare. Species of particular threat to Lake Whatcom Include Zebra Mussels, New Zealand Mud Snail, Asian Carp, and Viral hemorrhagic septicemia (VHS). Currently, none of Washington State’s 15 species identified as “most unwanted” are found in the lake. Eurasian Water milfoil is the only known aquatic invasive species in Lake Whatcom that is on Washington’s list of 50 unwanted species (13 of which are freshwater).
|This section does not cite any references or sources. (October 2012)|
The changing environment poses several threats to Lake Whatcom. The most direct effect of warming is the resulting warming of lake water. As water temperature raises the solubility of phosphorus increases, making it easier for phosphorus to enter the water column via the lake substrate. This increased phosphorus can continue to lower dissolved oxygen levels. Warming of the lake can also create more favorable conditions for invasive species survival as well as decreasing native species survival rates (Salmonids for example need cold water for hearing and survival). This warming will likely also lead to fluctuations in seasonal water levels and rainfall.
Lake Whatcom is home to 13 species of fish. Among these are 6 native species including: Kokanee Salmon (non-anadromous form of Sockeye), Cutthroat Trout, Longnose Sucker, Peamouth Chub, Sculpin and Threespine Stickleback. 3 species have purposefully been introduced to the lake: Bluegill, Rainbow Trout, and Smallmouth Bass. There are 4 species that have been illegally introduced: Brown Bullhead, Large Mouth Bass, Pumpkinseed Sunfish and Yellow Perch  The Department of Health has consumption advisories for small mouth bass and yellow perch, which can be found at the DOH Website
Watershed land use
Based on the 2000 census, there are about 13,000 residents within the Lake Whatcom Watershed. Current zoning will allow an increase to about 28,000. (Ecology, TMDL)
Land use on and around Lake Whatcom vary by basin. Most of Basin 1 falls in Bellingham City limits, which includes the most populous neighborhood, Silver Beach Creek. This is a high density residential neighborhood, with several public parks and open space tracts.
Basin 2 contains the Geneva neighborhood on the southern shore of the basin. This area has mixed zoning of urban residential, rural residential and rural forestry. The northern portion of the watershed in Basin 2 is zoned for rural, rural residential and rural forestry.
Basin 3 contains the Sudden Valley neighborhood which is high density residential. This is the primary residential population of Basin 3, as the rest of its watershed is zoned for commercial and rural forestry, as well as a small recreational open space and low density rural.
In 2001 the City of Bellingham placed a $5 per month fee on water bills to create a fund for purchasing land in the Lake Whatcom Watershed. To date 1,554 acres have been protected through the program, accounting for approximately 5% of the watershed. These properties are throughout the watershed, with the most (by acreage) found in Basin 3.
Whatcom County has a temporary ban on creations of new lots under 5 acres in the watershed. This ban has been in place since 2005.
- Moore, p.4
- Moore, F. Stanley, An Historical Geography of the Settlement Around Lake Whatcom Prior to 1920. Institute for Freshwater Studies, Bellingham, Washington, 1973.