Adding streamgage and reservoir sites into the water right landing page: Water Conservation Tool

[amabdallah]

As part of the Water Conservation Tool under scoping, we'd like to support users in accessing nearby streamgage and reservoir sites that can help in assessing or verifying conservation actions. For example, let's assume this water rights holder decides to participate in the voluntary, compensated, and temporary conservation program by not using water (fallowing their field) for one year. The compensating agency wants to verify this action is resulting in actual water savings. They'll mainly use OpenET. They may also want to use nearby streamgage and reservoir sites to see the actual flow or volume in the system.
https://westdaat.westernstateswater.org/details/right/UTwr_WR011144

Question 1: how do we add any existing nearby sites that measure water to this landing page? This is likely a toggle button that needs to be turned on.
Question 2 How do we determine which sites should be added and what defines "nearby here"? Would NLID help here? or should we allow the user to draw a polygon/shape that defines this area?

This functionality is relevant as well to water right owners who want to know water supply upstream of their point of diversion.