The Shoreline Management Act of 1971 which was created in order to help slow and reverse the damage that urbanization has upon Puget Sound. In Snohomish County there are seven basic land and water use element, all of which encourage and promote the general well being of the Puget Sound environment. However it is done in a realistic way because they take into fact that there will be growth, that cannot be stopped, so this plan has to do with how can we accommodate population growth and raise the quality of life for the Puget Sound environment.
==Hood Canal "Dead Zone"Hypoxia==
The Hood Canal is a long, narrow and deep fjord-like body of water. ItThere isare oftenseveral referredfactors that lead to aslow-oxygen aconditions ”Dead(hypoxia) Zone”in Hood Canal. It First is anthe areaunderwater thattopography isof literallythe suffocatingCanal. duetoThe lackdeepest parts of oxygen.the ThereCanal are manymore contributorsthan to600 thisfeet problemdeep, inbut at the Pugetentrance Sound.is Onea issill thethat underwateris topographyonly of150 thefeet canaldeep. IthasThis ansill entranceleads whichto issluggish verywater shallowexchange ofbetween 150Admiralty feetInlet and Hood Canal. ThiscreatesWater aexchange sillfrom liketides effectis makingalso watersluggish exchangein throughoutHood seasonsCanal anddue tidesto difficult.its Anothershape and depth. contributingfactorSecond is the supply of nutrients, primarily nitrate, to the euphotic zone. There are both natural and anthropogenicman-made sources of nutrients. The primary natural source is in ocean water that flushes Hood Canal. AnthropogenicMan-made sources include leaking septic systems, storm water runoff, agriculture and various other sources. The presence of nutrients leads to algae growth, which consumes oxygen when the algae die and decompose, contributing to the low oxygen conditions in these waters. LowoxygenThird concentrationsis duethe tosource poorof tidalocean exchangewater andthat high productivity are what have characterized theenters Hood Canal as a “Dead Zone”. Thepoor tidal exchangeCirculation in PugetHood SoundCanal is duelike tomost aestuaries: few factors. These include the flushing timefresh, andwarm thewater shapeflow ofout the sound. Flushing time depends onat the volume of the estuary, the volume of the tidal prism,surface and the number of tidal cycles per day. The tidal prism is knownreplaced asby thecold, differencesalty in the volume of the estuarywater at high and low tidedepth. AnequationThe forcold, ansalty approximateocean flushingwater timethat is:enters (FlushingHood timeCanal =comes Volume of estuary/ Volume of tidal prism)into Puget Sound hasfrom athe ratheropen longocean flushingand time,has becausenot itrecently isbeen ratherin largecontact comparedwith to its tidalthe prismatmosphere. Theshape of the sound prevents many of the inlets in the sound from flushing much at all; there isAs a lot of water movement in these inletsresult, but much of thethis water returnsis toinitially thesomewhat same inlet over and over again, and pollution and nutrients keep building updepleted in this same area of wateroxygen.
Low oxygen conditions are at there worst in the late summer, after several months of limited flushing and maximum plankton production near the surface. In some years, oxygen becomes sufficiently depleted that animals cannot survive. These kills may occur either locally or over a wide area. These issues are part of a current research program (Hood Canal Dissolved Oxygen Program).
