Gurbataccen yanayi

**Madogarar da ba ta da ma'ana (NPS) gurbacewar yanayi,** tana nufin gurɓacewar ruwa (ko ƙazanta), na ruwa ko iska da ba ta samo asali daga tushe guda ɗaya ba. Irin wannan gurɓacewar sau da yawa shi ne sakamakon tarawa na ƙananan gurɓatattun abubuwa da aka tattara daga babban yanki. Ya bambanta da gurɓacewar yanayi wanda ke fitowa daga tushe guda. Rashin gurɓataccen tushe gabaɗaya yana haifar da kwararar ƙasa, hazo, ajiyar yanayi, magudanar ruwa, ruwan  ko gyare-gyaren ruwa (ruwan sama da dusar ƙanƙara). inda gano gurɓatacciyar ƙasa zuwa tushe guda yana da wahala.  Gurɓacewar ruwan da ba ta da tushe tana shafar jikin ruwa daga tushe kamar gurbataccen ruwa daga wuraren noma da ke zubewa cikin kogi, ko tarkacen iska da ke kadawa zuwa teku. Gurɓacewar iska ta hanyar da ba ta da tushe tana shafar ingancin iska, daga tushe kamar rumbun hayaƙi ko bututun wutsiya na mota. Ko da yake waɗannan gurɓatattun abubuwan sun samo asali ne daga maɓuɓɓugar ruwa, ƙarfin jigilar dogon zango da maɓuɓɓuka masu yawa na gurɓataccen yanayi sun sa ya zama tushen gurɓatawar da ba ta dace ba; idan fitar da ruwa ya kasance a cikin ruwa ko cikin sararin samaniya a wuri guda, gurɓatar yanayi zai zama wuri guda Ko ɗaya.

Gurɓacewar ruwa mara tushe na iya samuwa daga wurare daban-daban ba tare da takamaiman mafita ko canje-canje don gyara matsalar ba, yana kuma mai da wahala a dai-daita shi. Rashin gurɓatar ruwa daga tushe yana da wuyar sarrafawa saboda yana fitowa daga ayyukan yau da kullun na mutane daban-daban, kamar takin lawn, amfani da magungunan kashe qwari, gina hanya ko ginin gini .  Sarrafa gurɓacewar yanayi mara tushe yana buƙatar inganta ayyukan birane da kewayen birni, ayyukan noma, ayyukan gandun daji da marinas.

Types of nonpoint source water pollution include sediment, nutrients, toxic contaminants and chemicals and pathogens. Principal sources of nonpoint source water pollution include: urban and suburban areas, agricultural operations, atmospheric inputs, highway runoff, forestry and mining operations, marinas and boating activities. In urban areas, contaminated storm water washed off of parking lots, roads and highways, called urban runoff, is usually included under the category of non-point sources (it can become a point source if it is channeled into storm drain systems and discharged through pipes to local surface waters). In agriculture, the leaching out of nitrogen compounds from fertilized agricultural lands is a nonpoint source water pollution. Nutrient runoff in storm water from "sheet flow" over an agricultural field or a forest are also examples of non-point source pollution.    

## Manyan nau'ikan (don gurbatar ruwa).

### Ruwan ruwa

Labe (sako da ƙasa ) ya hada da silt (lafiya barbashi) da kuma dakatar da daskararru (manyan barbashi). Ruwan  na iya shiga cikin ruwan saman daga ɓangarorin magudanan ruwa, da kuma zubar da ruwa a saman saboda rashin kyawun tsiron da aka rufe a birane da ƙauyuka.  Ruwan yana haifar da irin su turɓaya (girgije) a cikin ruwa, yana rage adadin hasken da ke kaiwa ƙasa mai zurfi, wanda zai iya hana haɓakar tsire-tsire na cikin ruwa da ke ƙarƙashin ruwa kuma saboda haka yana shafar nau'ikan da suka dogara da su, kamar kifi. Matakan turbidity kuma suna hana tsarin tsaftace ruwan sha.

Hakanan za'a iya fitar da ruwa daga tushe Ko ɓangare daban-daban. Tushen sun haɗa da wuraren gine- gine (ko da yake waɗannan tushen tushe ne, waɗanda za'a iya sarrafa su tare da sarrafa zaizayar ƙasa da sarrafa ruwa ), filayen noma, bankunan rafi, da kuma wuraren da ke da matsala sosai. 

### Abubuwan gina jiki.

Abubuwan rashin  gina jiki galibi suna nufin abubuwan da ba su da tushe daga magudanar ruwa, wuraren zubar da ƙasa, ayyukan dabbobi da filayen amfanin gona. Abubuwan da ke da mahimmanci guda biyu na damuwa shine phosphorus da nitrogen. 

Phosphorus wani sinadari ne wanda ke faruwa ta nau'i-nau'i da yawa waɗanda ba a iya samun su. Sanannen yana da yawa a cikin sludge na najasa na ɗan adam. Yana da babban sinadari a yawancin takin zamani da ake amfani da su don noma da kuma kan kaddarorin zama da na kasuwanci, kuma yana iya zama ƙayyadaddun sinadirai a cikin tsarin ruwan ruwa da wasu guraben ruwa . Phosphorus galibi ana jigilar su zuwa ga ruwa ta hanyar zaizayar ƙasa saboda yawancin nau'ikan phosphorus suna da alaƙa da barbashi na ƙasa. Yawan adadin phosphorus a cikin tsarin ruwa (musamman tafkunan ruwa, tafkunan ruwa, da tafkunan) yana haifar da yaduwar ƙananan algae da ake kira phytoplankton . Haɓaka samar da kwayoyin halitta saboda yawan girma na phytoplankton ana kiransa eutrophication . Alamar gama gari ta eutrophication ita ce furen algae wanda zai iya samar da tarkace mara kyau, ya fitar da nau'ikan tsire-tsire masu fa'ida, samar da mahadi masu haifar da ɗanɗano da wari, da guba ruwa saboda gubar da algae ke samarwa. Wadannan gubar matsala ce ta gaske musamman a tsarin da ake amfani da su wajen shan ruwan sha domin wasu guba na iya haifar da rashin lafiyar dan Adam kuma cire gubar yana da wahala da tsada. Rushewar ƙwayoyin cuta na furen algal yana cinye narkar da iskar oxygen a cikin ruwa, yana haifar da hypoxia tare da lahani ga kifaye da invertebrates na ruwa.

Nitrogen shi ne babban sinadari mai mahimmanci DA Ake amdani DA Shi a cikin takin mai magani, kuma gabaɗaya ya zama gurɓatacce a cikin ruwan gishiri ko tsarin estuarine brackish inda nitrogen ke iyakance abinci mai gina jiki. Hakazalika da phosphorus a cikin ruwa mai kyau, yawan adadin nitrogen da ake iya samu a cikin tsarin ruwa yana haifar da eutrophication da furen algae. Hypoxia wani sakamako ne na gama gari na eutrophication a cikin tsarin ruwa kuma yana iya yin tasiri ga manyan wuraren tudu, bays, da kusa da bakin tekun. Kowace lokacin rani, yanayi na hypoxic yana samuwa a cikin ruwa na ƙasa inda kogin Mississippi ya shiga Gulf of Mexico . A lokacin bazara na baya-bayan nan, iyakar iska ta wannan "yankin da ya mutu" ya yi daidai da yankin New Jersey kuma yana da babban illa ga kamun kifi a yankin.

Nitrogen yawanci ana jigilar shi ta ruwa azaman nitrate (NO 3 ). Yawanci ana ƙara nitrogen zuwa magudanar ruwa a matsayin Organic-N ko ammonia (NH 3 ), don haka nitrogen ya kasance a haɗe zuwa ƙasa har sai oxidation ya canza shi zuwa nitrate. Tun da an riga an shigar da nitrate gabaɗaya a cikin ƙasa, ruwan da ke tafiya cikin ƙasa (watau magudanar ruwa da magudanar tile ) shi ne ya fi dacewa ya kwashe shi, maimakon zubar da ruwa a Ko Ina.

### Gurɓatattun abubuwa masu guba da sinadarai.
Abubuwan da suka haɗa da ƙarfe masu nauyi kamar gubar, mercury, zinc, da cadmium, Organics kamar polychlorinated biphenyls (PCBs) da polycyclic aromatic hydrocarbons (PAHs), masu kashe wuta, da sauran abubuwa suna da juriya ga rushewa.  Waɗannan gurɓatattun abubuwa na iya fitowa daga wurare daban-daban da suka haɗa da najasar ruwan ɗan adam, ayyukan hakar ma'adinai, hayakin motoci, konewar mai, zubar da ruwa a birane, ayyukan masana'antu da wuraren share fage. 

Sinadarai masu guba sun haɗa da mahadi masu guba da mahaɗan inorganic . Waɗannan mahadi sun haɗa da wasu  magungunan kashe qwari kamar DDT, acids, da salts waɗanda ke da tasiri mai tsanani ga yanayin muhalli da jikin ruwa. Wadannan mahadi na iya yin barazana ga lafiyar mutane da nau'in ruwa yayin da suke jure wa rugujewar muhalli, don haka ba su damar dagewa a cikin muhalli.  Waɗannan sinadarai masu guba za su iya fitowa daga filayen noma, gandun daji, gonakin gonaki, wuraren gini, lambuna, lawns da wuraren share ƙasa. 

Acids da gishiri galibi sune gurɓatattun ƙwayoyin cuta daga filayen ban ruwa, ayyukan hakar ma'adinai, zubar da ruwa a birane, wuraren masana'antu da wuraren share ƙasa. 

### Cutar cututtuka.
Kwayoyin cuta su ne kwayoyin cuta da ƙwayoyin cuta waɗanda ake iya samu a cikin ruwa kuma suna haifar da cututtuka a cikin mutane.  Yawanci, ƙwayoyin cuta suna haifar da cuta lokacin da suke cikin kayan ruwan sha na jama'a. Kwayoyin cututtuka da aka samu a cikin gurɓataccen ruwa na iya haɗawa da Kamar haka:

* *Cryptosporidium parvum*
* *Giardia lamblia*
* *Salmonella*
* *Norovirus* da sauran ƙwayoyin cuta
* Kwayoyin tsutsotsi na parasitic (helminths).

Hakanan za'a iya gano ƙwayoyin cuta na Coliform da ƙwayoyin najasa a cikin ruwa.  Waɗannan ƙwayoyin cuta ne da aka saba amfani da su na gurɓacewar ruwa, amma ba ainihin musabbabin cututtuka ba. 

Kwayoyin cuta na iya gurɓata kwararar ruwa saboda rashin bin gudanar da ayyukan dabbobi, gurɓataccen tsarin najasa, rashin kulawa da sharar gida mara kyau, wuce gona da iri na najasar ɗan adam, gurɓataccen magudanar ruwa, da magudanar tsafta .  

## Babban tushen (don gurbataccen ruwa).

### Yankunan birni da na bayan gari.
Yankunan birni da na bayan gari sune manyan tushen gurɓatar ƙasa saboda yawan zubar da ruwa da ake samu saboda yawan shimfidar shimfidar wuri. Filayen da aka shimfida, kamar kwalta da siminti ba sa iya shiga cikin ruwa. Duk wani ruwan da ke da alaƙa da waɗannan saman zai gudana kuma yanayin da ke kewaye ya mamaye shi. Waɗannan filaye suna sauƙaƙa wa ruwan guguwa don ɗaukar ƙazanta zuwa cikin ƙasan da ke kewaye. 

Wuraren gine-gine sun kasance suna da ƙasƙan da ke cike da damuwa wanda ke saurin lalacewa ta hanyar hazo kamar ruwan sama, dusar ƙanƙara, da ƙanƙara . Bugu da ƙari, tarkacen da aka jefar a wurin za a iya kwashe su ta hanyar ruwa mai gudu kuma su shiga cikin yanayin ruwa. 

gurɓataccen ruwan guguwa da aka wanke a wuraren ajiye motoci, tituna da wasu manyan gurare, da lawn (yawanci suna ɗauke da takin zamani da magungunan kashe qwari ) ana kiransa ruwan gudu na birni . Ana yawan rarraba wannan zubar da jini a matsayin nau'in gurɓatawar NPS. Wasu mutane kuma na iya la'akari da shi a matsayin tushen tushe domin sau da yawa ana ratsa shi cikin tsarin magudanar ruwa na birni kuma ana fitar da shi ta bututu zuwa ruwan saman da ke kusa. Duk da haka, ba duk kwararar ruwa na birane ke gudana ta hanyar magudanar ruwa kafin shiga cikin ruwa ba. Wasu na iya kwarara kai tsaye zuwa cikin ruwa, musamman a yankunan masu tasowa da na bayan gari. Har ila yau, ba kamar sauran nau'o'in tushe ba, kamar fitar da masana'antu, masana'antun sarrafa najasa da sauran ayyuka, gurɓataccen ruwa a cikin birane ba za a iya danganta shi da aiki ɗaya ko ma rukuni na ayyuka ba. Saboda haka, saboda ba a iya ganowa da tsari cikin sauƙi ba, ana ɗaukar maɓuɓɓugar gurɓataccen ruwa a cikin birni a matsayin tushen gaskiya na gaskiya yayin da ƙananan hukumomi ke aiki don rage su Kawai.

Yawanci, a yankunan karkara, ana amfani da sinadarai don kula da lawn. Wadannan sinadarai na iya ƙarewa a cikin ruwa kuma su shiga cikin kewaye ta hanyar magudanar ruwa a cikin birni. Tun da ba a kula da ruwan da ke cikin magudanar ruwa kafin ya shiga cikin ruwa da ke kewaye, sinadarai suna shiga cikin ruwan kai tsaye.

Sauran mahimman hanyoyin zubar da ruwa sun haɗa da gyare-gyaren wurin zama da silviculture ( gandun daji).  

### Ayyukan noma.
Abubuwan gina jiki ( nitrogen da phosphorus ) yawanci ana amfani da su zuwa gonaki DA Ake amfani DA su azaman taki na kasuwanci, takin dabbobi, ko fesa ruwan sharar gari ko masana'antu (dabo) ko sludge. Hakazalika abubuwan gina jiki na iya shiga kwararowar ruwa daga ragowar amfanin gona, ruwan ban ruwa, namun daji, da kuma yanayin yanayi .  Labe (sako da ƙasa ) da aka wanke daga filayen wani nau'i ne na gurɓataccen aikin gona . gonakin da ke da manyan ayyukan kiwo da kiwon kaji, kamar gonakin masana'anta, galibi masu fitar da tushe ne. Ana kiran waɗannan wuraren "ayyukan ciyar da dabbobi" ko "masu ciyar da abinci" a cikin Amurka kuma suna ƙarƙashin ƙa'idodin gwamnati.  

Ayyukan noma suna da kaso mai yawa na duk gurɓacewar tushen tushe a Amurka. Lokacin da ake noma manyan gonaki don shuka amfanin gona, yakan fallasa kuma ya sassauta ƙasa da aka binne. Wannan yana sa ƙasan da aka fallasa ta zama mafi haɗari ga zaizayar ƙasa yayin damina . Hakanan yana iya ƙara yawan taki da magungunan kashe qwari da ake ɗauka a cikin ruwa na kusa. 

### Abubuwan shigar da yanayi.
Tushen yanayin shine tushen abubuwan da ba a iya amfani da su ba saboda ana jigilar su daga tushen gurɓataccen iska zuwa masu karɓa a ƙasa.   Yawanci, wuraren masana'antu, kamar masana'antu, suna fitar da gurɓataccen iska ta wurin hayaƙi . Ko da yake wannan mahimmin tushe ne, saboda yanayin rarraba, sufuri mai nisa, da maɓuɓɓuka masu yawa na gurɓataccen abu, ana iya la'akari da shi a matsayin tushen da ba shi da ma'ana a yankin da aka ajiye. Abubuwan da ke cikin yanayi waɗanda ke shafar ingancin kwararar ruwa na iya zuwa daga bushewa a bushewa tsakanin abubuwan da ke faruwa na guguwa da jika a lokacin abubuwan da suka faru na guguwa. Tasirin zirga-zirgar ababen hawa a kan jika da busassun ajiyewa da ke faruwa a kan ko kusa da manyan tituna, titin titi, da wuraren ajiye motoci na haifar da rashin tabbas a girman ma'aunin yanayi daban-daban a cikin ruwa. Cibiyoyin sadarwar da suka wanzu waɗanda ke amfani da ƙa'idodi da suka isa don ƙididdige waɗannan ƙididdiga da lodi ba sa auna yawancin abubuwan abubuwan ban sha'awa kuma waɗannan cibiyoyin sadarwa ba su da wasu yawa don samar da ƙididdiga masu kyau a ma'aunin gida  

### Ruwan titin babbar hanya.
Rushewar babbar hanya yana da ɗan ƙaramin kaso amma yaɗuwar duk gurɓatar tushen da ba ta da tushe.       Harned a shekarata (1988) ya kiyasta cewa nauyin da ke gudu ya ƙunshi faɗuwar yanayi (9%), ajiyar abin hawa (25%) da kayan gyaran manyan hanyoyi (67%) ya kuma kiyasta cewa kusan kashi 9 cikin ɗari na waɗannan lodin an sake horar da su a cikin yanayi. 

### Ayyukan gandun daji da ma'adinai
Ayyukan gandun daji da hakar ma'adinai na iya samun mahimman bayanai ga gurɓacewar tushen tushe.

#### Gandun daji.
Ayyukan gandun daji suna rage adadin bishiyoyi a wani yanki, don haka rage yawan iskar oxygen a yankin. Wannan aikin, haɗe tare da injuna masu nauyi (masu girbi, da sauransu) mirgina ƙasa yana ƙara haɗarin zaizayar ƙasa .

#### Ma'adinai.
Ana ɗaukar ayyukan hakar ma'adinai masu aiki tuƙuru DA jajircewa, duk da haka zubar da ruwa daga ayyukan hakar ma'adinai da aka yi watsi da shi yana ba da gudummawa ga gurɓatar tushen tushe. A cikin ayyukan hakar ma'adinai, ana cire saman dutsen don fallasa ma'adinan da ake so. Idan ba a kwato wannan yanki da kyau da zarar an gama hakar ma'adinan, zaizayar ƙasa na iya faruwa. Bugu da ƙari, ana iya samun halayen sinadarai tare da iska da sabon dutsen da aka fallasa don haifar da zubar da ruwa mai acidic. Ruwan da ke fitowa daga ma'adinan ƙasa da aka watsar na iya zama mai yawan acidic. Wannan zai iya shiga cikin jikin ruwa mafi kusa kuma ya canza pH a cikin yanayin ruwa. 

### Marinas da ayyukan jirgin ruwa.
Sinadaran da ake amfani da su don kula da kwale-kwale, kamar fenti, kaushi, da mai suna samun hanyar shiga ruwa ta cikin ruwa. Bugu da ƙari, zubar da mai ko ɗibar mai kai tsaye a cikin ruwa daga kwale-kwale yana ba da gudummawa ga gurɓatar ƙasa mara tushe. Matakan sinadirai da ƙwayoyin cuta suna ƙaruwa ta wurin wuraren sharar da ba a kula da su ba a kan jirgin ruwa da tashoshin fitar da famfo. 

## Sarrafa (don gurbataccen ruwa).

### Yankunan birni da na bayan gari
Don shawo kan gurɓacewar tushen tushe, ana iya aiwatar da wasu hanyoyi daban-daban a cikin birane da na kewayen birni. Gilashin buffer yana ba da shingen ciyawa tsakanin kayan da ba za a iya jurewa ba kamar wuraren ajiye motoci da tituna, da kuma mafi kusa da ruwa. Wannan yana bawa ƙasa damar ɗaukar duk wani gurɓataccen gurɓataccen ruwa kafin ta shiga cikin tsarin ruwa na gida. Ana iya gina tafkuna masu riƙewa a wuraren magudanar ruwa don ƙirƙirar maɓuɓɓugar ruwa tsakanin gurɓataccen ruwa da yanayin ruwa. Guduwar ruwa da guguwar ruwa suna magudawa a cikin tafkin da ake ajiyewa da ke ba da damar gurɓatattun abubuwa su daidaita su zama tarko a cikin tafki. Yin amfani da lafazin lafazin yana ba da damar ruwan sama da ruwan guguwa su zube cikin ƙasan daf ɗin, wanda hakan zai rage yawan kwararar da ke kwarara cikin ruwa kai tsaye. Hakanan ana amfani da hanyoyin maidowa kamar gina wuraren dausayi don rage gudu da kuma shawo kan gurɓata ruwa.

Wuraren gine-gine na aiwatar da matakai masu sauƙi don rage ƙazanta da zubar da ruwa. Da fari dai, ana kafa shingen shinge ko shinge a kusa da wuraren gine-gine don rage yawan laka da manyan kayan da ke zubewa cikin ruwa da ke kusa. Na biyu, shimfida ciyawa ko bambaro a kan iyakar wuraren gine-ginen kuma yana aiki don rage gurɓatar ƙasa mara tushe Ko inganci. 

A cikin yankunan da tsarin septic na gida ɗaya ke aiki, ƙa'idodin ƙananan hukumomi na iya tilasta kiyaye tsarin septic don tabbatar da bin ka'idodin ingancin ruwa. A Washington (jihar), an ƙirƙiro wani sabon salo ta hanyar ƙirƙirar "gundumar kariyar kifi" lokacin da aka rage girman gadon kifin kifi na kasuwanci ko na nishaɗi saboda ci gaba da gurɓacewar tushen tushe. Gundumar kariyar shellfish yanki ne na yanki da gundumar ta keɓance don kare ingancin ruwa da albarkatun ruwa, kuma yana ba da hanyar samar da kuɗaɗen gida don sabis na ingancin ruwa don sarrafa tushen gurɓataccen ruwa.  Aƙalla gundumomi biyu na kariyar kifi a kudancin Puget Sound sun ƙaddamar da tsarin aiki da buƙatun kulawa tare da kuɗin shirin da ke daure kai tsaye da harajin kadarorin. 

### Ayyukan noma.
Don sarrafa laka wato ƙasa da kwararar ruwa, manoma za su iya amfani da hanyoyin sarrafa zaizayar ƙasa don rage kwararar ruwa da riƙe ƙasa a filayensu. Dabarun gama gari sun haɗa da noman kwane-kwane, dasa shuki, jujjuyawar amfanin gona , dasa amfanin gona na yau da kullun ko shigar da magudanan ruwa .    *Yin noman kiyayewa* ra'ayi ne da ake amfani da shi don rage kwararar ruwa yayin dasa sabon amfanin gona. Manomin ya bar wasu amfanin gona da aka shuka a baya a cikin ƙasa don hana kwararar ruwa yayin aikin shuka. 

Ana amfani da kayan abinci na gina jiki a gonaki a matsayin takin kasuwanci; taki na dabba; ko fesa ruwan sharar gari ko na masana'antu wato kamfani (ruwan taki) ko sludge. Hakazalika abubuwan gina jiki na iya shiga kwararowar ruwa daga ragowar amfanin gona, ruwan ban ruwa, namun daji, da kuma yanayin yanayi .  Manoma na iya haɓakawa da aiwatar da tsare-tsaren sarrafa kayan abinci don rage yawan amfani da abubuwan gina jiki.  

Don rage tasirin magungunan kashe qwari, manoma na iya amfani da dabarun Gudanar da Kwari (IPM) (wanda zai iya haɗawa da sarrafa kwari ) don kula da sarrafa kwari, rage dogaro da magungunan kashe qwari, da kare ingancin ruwa .  

### Ayyukan gandun daji.
Tare da kyakkyawan tsari na jeri na biyun hanyoyin shiga, wanda kuma ake kira hanyoyin skid, na iya rage adadin laka da aka samar. Ta hanyar tsara wurin hanyoyin da nisa daga ayyukan katako kamar yadda zai yiwu tare da daidaita hanyoyin tare da ƙasa, zai iya rage adadin sako-sako da ke cikin ruwa. Bugu da ƙari, ta hanyar sake dasa bishiyoyi a ƙasa bayan an yi shuka Ko binne amfani, yana samar da tsari ga ƙasa don dawo da kwanciyar hankali tare da maye gurbin yanayin da aka bushe. 

### Marinas.
Shigar da bawuloli na kashe akan famfunan mai a tashar jirgin ruwa na iya taimakawa rage yawan zubewa cikin ruwa. Bugu da ƙari, tashoshin fitar da famfo waɗanda ke da sauƙin isa ga masu jirgin ruwa a cikin magudanar ruwa na iya samar da wuri mai tsabta inda za a zubar da sharar tsafta ba tare da zubar da shi kai tsaye cikin ruwa ba. A ƙarshe, wani abu mai sauƙi kamar samun kwantena na shara a kusa da marina na iya hana manyan abubuwa shiga a cikin ruwa. 

## Misalai na ƙasa.

### Amurka
Gurbatacciyar hanyar da ba ta da tushe ita ce kan gaba wajen haifar da gurɓacewar ruwa a ƙasar Amurka a yau, tare da gurɓataccen kwararar ruwa daga aikin noma da gyaran ruwa.  

#### Doka na gurɓacewar Tushen Madogara a Amurka.
Ana yin ma'anar tushen da ba ta da ma'ana a ƙarƙashin Dokar Ruwa mai Tsabta ta Amurka kamar yadda Hukumar Kare Muhalli ta Amurka (EPA) ta fassara. Doka ba ta tanadi tsarin dokokin tarayya kai tsaye na kafofin da ba su da tushe, amma jihohi da ƙananan hukumomi na iya yin hakan bisa ga dokokin jiha. Misali, jihohi da dama sun dauki matakin aiwatar da nasu shirye-shiryen gudanar da nasu wuraren kamar yankunan bakin tekun nasu, wadanda dukkansu sai sun samu amincewar hukumar kula da teku da iska da kuma EPA.  Makasudin waɗannan shirye-shiryen da ma dai dai su ne ƙirƙirar ginshiƙai waɗanda ke ƙarfafa rage gurɓacewar yanayi a duk faɗin jihar ta hanyar haɓakawa da haɓaka tsarin da suka wanzu.  Shirye-shirye a cikin waɗannan jahohi da ƙananan hukumomi suna duban mafi kyawun ayyukan gudanarwa (BMPs) don cimma burinsu na nemo hanya mafi ƙarancin tsada don rage mafi girman ƙazanta. Ana iya aiwatar da BMPs don zubar da ruwa na noma da na birni, kuma yana iya zama ko dai na tsari ko hanyoyin da ba na tsari ba. Dan haka Hukumomin tarayya, ciki har da EPA da Sabis na Kare Albarkatun Ƙasa, sun yarda kuma sun ba da jerin BMPs da aka saba amfani da su don nau'o'i daban-daban na gurɓataccen tushen tushe. 

#### tanadin Dokar Ruwa mai Tsabta ta Amurka ga jihohi.
Majalisa ta ba da izini ga shirin CWA sashi na 319, a cikin shekarata 1987. Ana ba da tallafi ga jihohi, yankuna, da kabilu don ƙarfafa aiwatarwa da ci gaba a cikin manufofin.  Doka tana buƙatar duk jihohi suyi aiki da shirye-shiryen gudanarwa na NPS. EPA na buƙatar sabunta shirye-shirye na yau da kullun don gudanar da yadda ya kamata a sarrafa yanayin ruwansu da ke canzawa koyaushe, da kuma tabbatar da ingantaccen amfani da kudade da albarkatun tallafi na 319. 

Dokar sake ba da izini ga shiyar bakin teku (CZARA) na shekarar 1990, ta ƙirƙiri wani shiri a ƙarƙashin Dokar Kula da Yankunan Tekun da ke ba da umarnin haɓaka matakan sarrafa gurɓataccen tushen tushen tushen da ba a taɓa gani ba a cikin jihohin da ke da ruwan teku.  CZARA na buƙatar jihohin da ke da bakin teku su aiwatar da matakan gudanarwa don gyara gurɓataccen ruwa, da kuma tabbatar da cewa an aiwatar da samfuran waɗannan matakan sabanin karɓuwa. 

## Duba wasu abubuwan.

* Rushewar abinci mai gina jiki na noma.
* stochastic empirical loading da dilution model.
* Fihirisar jihar Trophic (mai nuna ingancin ruwa).
* Surface-water hydrology.
* ingancin ruwa.
* Samfuran ingancin ruwa.

## Hanyoyin haɗi na waje.

## Manazarta.

* US EPA-Shirin Gudanar da Tushen Mahimmanci