How do I resolve issues with my translation of a snippet about 观潮 (guāncháo = tide watching) from a 4-th grade Chinese book? This is the first part of 语文四年级上册 (a grade-4 Chinese textbook), and the transcript is here 观潮 (guāncháo = tide watching).


  钱塘江大潮，自古以来被称为天下奇观。
  　　农历八月十八是一年一度的观潮日。这一天早上，我们来到了海宁市的盐官镇，据说这里是观潮最好的地方。我们随着观潮的人群，登上了海塘大堤。宽阔的钱塘江横卧在眼前。江面很平静，越往东越宽，在雨后的阳光下，笼罩着一层蒙蒙的薄雾。镇海古塔、中山亭和观潮台屹立在江边。远处，几座小山在云雾中若隐若现。江潮还没有来，海塘大堤上早已人山人海。大家昂首东望，等着，盼着。


I translate this to:


  Qiantang River's big lake, since ancient times has been known as Earthly wonder.
  The lunar calendar's 8-th month 18-th day is the annual tide-watching.  This day in the morning, we come to Haining city's Yanguan district; reportedly, here is tide-watching's best place.  We, along with a tide-watching group, climb over the large seawall [海塘大堤].  Wide Qiantang River reclines [横卧] in front of our eyes. The surface of the river is tranquil, incrementally moving east and wider [越往东越宽]; in the after-rain sunshine, there is an enveloping layer of drizzly mist. In Zhenhai distict and Guta district, Zhongshan pavilion and tide-watching terraces tower on the river bank.  In the distance, a few small mountains in the mist are faintly discernible.  The river's tide has not yet come, and on the large seawall for a long time there's been a vast crowd.  Everyone [昂首东望 (?)], waiting, anticipating.


I encounter a few issues here:


I'm not sure how to interpret 海塘大堤 (hǎitáng dàdī): we have both 海塘 (seawall) and 大堤 (levee) which seem redundant.  Could 海塘 be the name of the 大堤?
横卧 (héngwò) translates to "to recline", but it seems strange that a river "reclines".  This doesn't make sense to me.
I'm not sure if I'm interpreting 越往东越宽 correctly.  I think it means the river (or lake) is incrementally moving eastwards and getting wider. Google Translate gives "the more eastward the wider", which is not so clear to me.
I unclear about 昂首东望 (ángshǒu dōng wàng): 昂首 means to raise one's head, but 东 means "East" and 望 means "to hope".  Google Translate gives "looking east", which is probably accurate.


Question: How do I resolve issues with my translation of a 观潮?
海塘大堤 is a particular type of levee. Not all levees are seawalls. See this and this.

横卧：It as a figurative use. The river is there like a person lying there. Something like that.

越往东越宽: There is no verb here. So no "moving".
往 is not a verb here. It is a preposition that means "towards".
This just describes the rive, which is wider in the eastward. "The more eastward the wider".

昂首东望: 望 is not "hope" here. It means "look". The phrase means: raising one's head and looking east.